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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2025

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission File Number: 1-33409

T-MOBILE US, INC.

(Exact name of registrant as specified in its charter)


Delaware						20-0836269
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification No.)

12920 SE 38th Street

Bellevue, Washington

(Address of principal executive offices)

98006-1350

(Zip Code)



(425)			378-4000
(Registrant’s telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock, par value $0.00001 per share

TMUS

The NASDAQ Stock Market LLC

3.550% Senior Notes due 2029

TMUS29

The NASDAQ Stock Market LLC

3.700% Senior Notes due 2032

TMUS32

The NASDAQ Stock Market LLC

3.150% Senior Notes due 2032

TMUS32A

The NASDAQ Stock Market LLC

3.850% Senior Notes due 2036

TMUS36

The NASDAQ Stock Market LLC

3.500% Senior Notes due 2037

TMUS37

The NASDAQ Stock Market LLC

3.800% Senior Notes due 2045

TMUS45

The NASDAQ Stock Market LLC

6.250% Senior Notes due 2069

TMUSL

The NASDAQ Stock Market LLC

5.500% Senior Notes due March 2070

TMUSZ

The NASDAQ Stock Market LLC

5.500% Senior Notes due June 2070

TMUSI

The NASDAQ Stock Market LLC

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☒ No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes No ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.


Large accelerated filer	☒	Accelerated filer	☐
Non-accelerated filer	☐	Smaller reporting company	☐
		Emerging growth company	☐

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If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ☐ No ☒

As of June 30, 2025, the aggregate market value of the voting and non-voting common equity held by non-affiliates was $112.4 billion based on the closing sale price as reported on the NASDAQ Global Select Market. As of February 6, 2026, there were 1,101,862,739 shares of common stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Part III of this Annual Report on Form 10-K will be incorporated by reference from certain portions of the definitive Proxy Statement for the Registrant’s 2026 Annual Meeting of Stockholders, which definitive Proxy Statement will be filed with the Securities and Exchange Commission pursuant to Regulation 14A or will be included in an amendment to this Report.

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T-Mobile US, Inc.

Form 10-K

For the Year Ended December 31, 2025

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PART I.
	Item 1.	Business	6
	Item 1A.	Risk Factors	12
	Item 1B.	Unresolved Staff Comments	25
	Item 1C.	Cybersecurity	25
	Item 2.	Properties	27
	Item 3.	Legal Proceedings	27
	Item 4.	Mine Safety Disclosures	27

PART II.
	Item 5.	Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities	28
	Item 6.	[Reserved]	29
	Item 7.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	30
	Item 7A.	Quantitative and Qualitative Disclosures About Market Risk	55
	Item 8.	Financial Statements and Supplementary Data	56







	Item 9.	Changes in and Disagreements with Accountants on Accounting and Financial Disclosure	119

	Item 9A.	Controls and Procedures	119
	Item 9B.	Other Information	120
	Item 9C.	Disclosure Regarding Foreign Jurisdictions that Prevent Inspections	120









PART III.
	Item 10.	Directors, Executive Officers and Corporate Governance	121
	Item 11.	Executive Compensation	121
	Item 12.	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters	121
	Item 13.	Certain Relationships and Related Transactions, and Director Independence	121
	Item 14.	Principal Accountant Fees and Services	121
PART IV.
	Item 15.	Exhibits and Financial Statement Schedules	121
	Item 16.	Form 10-K Summary	122
		Index to Exhibits	123
		Signatures	137

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Cautionary Statement Regarding Forward-Looking Statements

This Annual Report on Form 10-K (“Form 10-K”) of T-Mobile US, Inc. (“T-Mobile,” “we,” “our,” “us” or the “Company”) includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical fact, including information concerning our future results of operations, are forward-looking statements. These forward-looking statements are generally identified by the words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “could” or similar expressions. Forward-looking statements are based on current expectations and assumptions, which are subject to risks and uncertainties that may cause actual results to differ materially from the forward-looking statements. The following important factors, along with the Risk Factors included in Part I, Item 1A of this Form 10-K, could affect future results and cause those results to differ materially from those expressed in the forward-looking statements:

•competition, industry consolidation and changes in the market for wireless communications services and other forms of connectivity;

•cyberattacks, disruptions, data loss or other security breaches;

•our inability to adopt and deploy network technologies in a timely and effective manner;

•our inability to effectively execute our digital transformation and drive customer and employee adoption of emerging technologies;

•our inability to retain or motivate key personnel, hire qualified personnel or maintain our corporate culture;

•system failures and business disruptions, allowing for unauthorized use of or interference with our network and other systems;

•the scarcity and cost of additional wireless spectrum, and regulations relating to spectrum use;

•the timing and effects of any pending and future acquisition, investment, joint venture, merger, or divestiture involving us, including our inability to obtain any required regulatory approval necessary to consummate any such transactions or to achieve the expected benefits of such transactions;

•adverse economic, political or market conditions in the U.S. and international markets, including changes resulting from increases in inflation or interest rates, tariffs and trade restrictions, supply chain disruptions, fluctuations in global currencies, immigration policies, and impacts of geopolitical instability, such as the Ukraine-Russia, Iran-Israel and Israel-Hamas wars and further escalations thereof;

•operational delays, higher procurement and operational costs, and increased regulatory and compliance complexities, for example, as a result of changes to trade policies, including higher tariffs, restrictions and other economic disincentives to trade;

•our inability to successfully deliver new products and services;

•any failure or inability of our third parties (including key suppliers) to provide products or services for the operation of our business;

•sociopolitical volatility and polarization and risks related to environmental, social and governance matters;

•our substantial level of indebtedness and our inability to service our debt obligations in accordance with their terms;

•changes in the credit market conditions, credit rating downgrades or an inability to access debt markets;

•our inability to maintain effective internal control over financial reporting;

•compliance with the current regulatory framework, including our national security obligations, and any changes in regulations or in the regulatory framework under which we operate;

•laws and regulations relating to the handling of privacy, data protection and artificial intelligence (“AI”);

•unfavorable outcomes of and increased costs from existing or future regulatory or legal proceedings;

•difficulties in protecting our intellectual property rights or if we infringe on the intellectual property rights of others;

•our offering of regulated financial services products and exposure to a wide variety of state and federal regulations;

•new or amended tax laws or regulations or administrative interpretations and judicial decisions affecting the scope or application of tax laws or regulations;

•our wireless licenses, including those controlled through leasing agreements, are subject to renewal and may be revoked;

•our exclusive forum provision as provided in our Certificate of Incorporation;

•interests of Deutsche Telekom AG (“DT”), our controlling stockholder, which may differ from the interests of other stockholders;

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•our current and future stockholder return programs may not be fully utilized, and our share repurchases and dividend payments pursuant thereto may fail to have the desired impact on stockholder value; and

•future sales of our common stock by DT and our inability to attract additional equity financing outside the United States due to foreign ownership limitations by the Federal Communications Commission (“FCC”).

Given these risks and uncertainties, readers are cautioned not to place undue reliance on such forward-looking statements. We undertake no obligation to revise or publicly release the results of any revision to these forward-looking statements, except as required by law.

In addition, historical, current, and forward-looking environmental sustainability related statements may be based on standards for measuring progress that are still developing and internal controls and processes that continue to evolve. These initiatives are subject to additional risks and uncertainties, including regarding the evolving nature of data availability, quality, and assessment; related methodological concerns; our ability to implement various initiatives under expected timeframes, cost, and complexity; our dependency on third parties to provide certain information and to comply with applicable laws and policies; and other unforeseen events or conditions. For example, we note that standards and expectations regarding greenhouse gas (“GHG”) accounting and the processes for measuring and counting GHG emissions and GHG emission reductions are evolving, and it is possible that our approaches both to measuring our emissions and to reducing emissions and measuring those reductions may be, either currently by some stakeholders or at some point in the future, considered inconsistent with common or best practices with respect to measuring and accounting for such matters, and reducing overall emissions. These factors, as well as others, may cause results to differ materially and adversely from those expressed in any of our forward-looking statements. Additionally, we may provide information that is not necessarily material for SEC reporting purposes but that is informed by various other standards and frameworks (including standards for the measurement of underlying data), internal controls, and assumptions or third-party information that are still evolving and subject to change. Our disclosures based on any standards may change due to revisions in framework requirements, availability of information, changes in our business or applicable governmental policies, or other factors, some of which may be beyond our control.

Investors and others should note that we announce material information to our investors using our investor relations website (https://investor.t-mobile.com), newsroom website (https://t-mobile.com/news), press releases, SEC filings and public conference calls and webcasts. We intend to also use certain social media accounts as a means of disclosing information about us and our services and for complying with our disclosure obligations under Regulation FD (the @TMobileIR X account (https://x.com/TMobileIR), the @SriniGopalan X account (https://x.com/SriniGopalan) and our CEO’s LinkedIn account (https://www.linkedin.com/in/srini-gopalan/), both of which Mr. Gopalan also uses as a means for personal communications and observations, and the @TMobileCFO X account (https://x.com/tmobilecfo) and our Chief Financial Officer’s LinkedIn account (https://www.linkedin.com/in/peter-osvaldik-3887394), both of which Mr. Osvaldik also uses as a means for personal communication and observations). The information we post through these social media channels may be deemed material. Accordingly, investors should monitor these social media channels in addition to following our press releases, SEC filings and public conference calls and webcasts. The social media channels that we intend to use as a means of disclosing the information described above may be updated from time to time as listed on our investor relations website.

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PART I.

Item 1. Business

Business Overview and Strategy

Un-carrier Strategy

As America’s supercharged Un-carrier, we have disrupted the telecommunications industry by actively engaging with and listening to our customers and focusing on eliminating their pain points. Our customers benefit from what we believe is an unmatched combination of the best value and best network, alongside an unwavering focus on offering them the best possible service experience and an undisputable drive for disruptive innovation in wireless and beyond. This includes providing added value and what we believe is an exceptional experience while implementing signature Un-carrier initiatives that have changed the industry. We ended annual service contracts, overages, unpredictable international roaming fees and data buckets, among other things. We are inspired by a relentless focus on customer experience, consistently delivering award-winning customer experience, which drives our customer satisfaction levels while enabling operational efficiencies.

With what we believe is America’s best network, with the largest, fastest, most awarded and most advanced 5G network, the Un-carrier strives to offer customers unrivaled coverage and capacity where they live, work and travel. We believe our network is the foundation of our success and powers everything we do. Our dense and multi-layer network provides an unmatched 5G and overall network experience to our customers, which consists of our foundational layer of low-band, mid-band and millimeter-wave (“mmWave”) spectrum licenses (see “Spectrum Position” below). This multilayer portfolio of spectrum broadens and deepens our nationwide 5G network, enabling accelerated innovation and increased competition in the U.S. wireless telecommunications industry.

We continue to expand the footprint and improve the quality of our network, enabling us to provide what we believe are outstanding wireless experiences for customers who should not have to compromise on quality and value. Our network allows us to deliver new, innovative products and services, such as our 5G broadband fixed wireless product, with the same customer experience focus and industry-disrupting mindset that we have adopted in our journey to redefine wireless communications services in the United States in the customers’ favor.

As part of our relentless, customer-first focus, we are transforming into an AI-enabled, data-informed, digital-first organization to continue delivering differentiated experiences to our customers. Leveraging the latest AI technology and digital capabilities, we are pioneering new approaches to serving customers with a platform to better anticipate and proactively solve their issues, offering personalized self-service options and taking authorized actions on their behalf, while simultaneously creating large-format customer experience stores for customers looking for an immersive experience. Our comprehensive T-Life app is radically simplifying customer experiences with upgrades, add-a-line, and switching transactions all available at customers’ fingertips, allowing customers and prospects to transact with us wherever and whenever they want.

Our Operations

As of December 31, 2025, we provide wireless communications and broadband services to 142.4 million postpaid and prepaid customers and generate revenue by providing affordable wireless communications and broadband services to these customers, as well as a wide selection of wireless devices and accessories. We also provide wholesale wireless services to various partners, who then offer the services for sale to their customers. Our most significant expenses relate to operating and expanding our network, providing a full range of devices, acquiring and retaining high-quality customers and compensating employees. We provide services, devices and accessories across our flagship brands, T-Mobile, Metro by T-Mobile and Mint Mobile, through our T-Mobile and Metro by T-Mobile owned and operated retail stores, as well as through our websites (www.t-mobile.com, www.metrobyt-mobile.com and www.mintmobile.com), T-Mobile, Metro by T-Mobile and Mint Mobile apps, customer care channels and through national retailers. In addition, we sell devices to dealers and other third-party distributors for resale through independent third-party retail outlets and a variety of third-party websites. The information on our websites is not part of this Form 10-K. See Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations for additional information.

Services and Products

We provide wireless communications and broadband services through a variety of service plan options. We also offer for sale to customers a wide selection of wireless devices, including smartphones, wearables, tablets, 5G broadband gateways and other mobile communication devices that are manufactured by various suppliers.

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We offer a full suite of service plans that provide customers with the features that meet their lifestyle and daily needs. Our most popular current service plan offerings are our premium Experience plans, including Experience More and Experience Beyond, which include unlimited talk, text and data on our network, 5G access at no extra cost, scam protection features, popular streaming subscriptions, in-flight Wi-Fi, access to the same device offers as new customers and more. We also offer an Essentials rate plan for customers who want the basics at a lower price point, and specific rate plans to qualifying customers, including Military and Veterans, First Responder and 55+.

At the time of device purchase, qualified customers can finance all or a portion of the individual device or accessory purchase price over an installment period, generally of 24 months, using an equipment installment plan (“EIP”).

In addition to our wireless communications services, we offer complementary broadband services including 5G broadband, which is a fixed wireless product available to tens of millions of domestic households utilizing the excess capacity of our nationwide 5G network, and fiber, expanding broadband access and choices for some consumers. With our 5G broadband and fiber plans, customers can access the internet without worrying about annual service contracts, data overages or hidden fees.

We also provide products and services that are complementary to our wireless communications and broadband services, including device protection, financial services and advertising.

Customers

We provide wireless communications and broadband services to a variety of customers needing connectivity, but focus primarily on two categories of customers:

•Postpaid customers generally are qualified to pay after receiving service utilizing phones, 5G broadband gateways, fiber connections, mobile internet devices (including tablets and hotspots), wearables, DIGITS and other connected devices (including SyncUP and internet of things (“IoT”)). We serve consumers as well as business customers, who are provided services under the T-Mobile for Business brand.

•Prepaid customers generally pay for service in advance. We serve prepaid customers under the T-Mobile, Metro by T-Mobile, Mint Mobile and Ultra Mobile brands.

We also provide Machine-to-Machine (“M2M”) and Mobile Virtual Network Operator (“MVNO”) customers access to our network. This access and the customer relationship are managed by wholesale partners, with whom we have commercial agreements permitting them to sell services utilizing our network.

We generate the majority of our service revenues by providing wireless communications and broadband services to postpaid and prepaid customers. Our ability to attract and retain postpaid and prepaid customers is important to our business in the generation of service revenues, equipment revenues and other revenues. In 2025, our service revenues generated by providing wireless communications and broadband services by customer category were:

•81% Postpaid customers;

•15% Prepaid customers; and

•4% Wholesale and other services.

Substantially all of our revenues for the years ended December 31, 2025, 2024 and 2023, were earned in the United States, including Puerto Rico and the U.S. Virgin Islands.

Network Strategy

Utilizing our multilayer spectrum portfolio, our mission is to become “Famous for Network” and we have been recognized by third parties for having America’s best network. We have deployed low-band, mid-band and mmWave spectrum dedicated for 5G across our dense and broad network to create what we believe is America’s largest, fastest, most awarded and most advanced 5G network.

We believe our spectrum position and focus on technology leadership will continue to drive network differentiation. Our innovative Customer-Driven Coverage (“CDC”) approach to network investments, and leadership in deploying the latest network technologies including Massive Multiple-input Multiple-output (“Massive MIMO”), Voice over New Radio (“VoNR”), Low Latency, Low Loss, Scalable Throughput (“L4S”), four-carrier and higher order aggregation, dynamic network slicing and the U.S.’s first broad deployment of 5G Advanced, are enabled by our scaled nationwide 5G standalone network.

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We are also part of an alliance working to bring Radio Access Network (“RAN”) and AI innovation closer together to deliver transformational network experiences in the future.

Spectrum Position

We provide wireless communications services utilizing low-band spectrum licenses covering our 600 MHz and 700 MHz spectrum, mid-band spectrum licenses, such as Advanced Wireless Services (“AWS”), Personal Communications Services (“PCS”) and 2.5 GHz spectrum, and mmWave spectrum.

•We controlled an average of 394 MHz of combined low- and mid-band spectrum nationwide as of December 31, 2025. This spectrum is comprised of:

•An average of 43 MHz in the 600 MHz band;

•An average of 12 MHz in the 700 MHz band;

•An average of 14 MHz in the 800 MHz band;

•An average of 42 MHz in the 1700 MHz AWS band;

•An average of 68 MHz in the 1900 MHz PCS band;

•An average of 185 MHz in the 2.5 GHz band;

•An average of 3 MHz in the 3.45 GHz band; and

•An average of 27 MHz in the C-band.

•We controlled an average of 1,059 GHz of combined mmWave spectrum licenses as of December 31, 2025.

•In September 2023, we entered into a License Purchase Agreement with Comcast Corporation and its affiliate, Comcast OTR1, LLC (together with Comcast Corporation, “Comcast”) pursuant to which we will acquire spectrum in the 600 MHz band in exchange for total cash consideration of between $1.2 billion and $3.3 billion. On January 13, 2025, we and Comcast entered into an amendment to the License Purchase Agreement pursuant to which we will acquire additional spectrum. Subsequent to the amendment, the total cash consideration for the transaction is between $1.2 billion and $3.4 billion. See Note 7 – Goodwill, Spectrum License Transactions and Other Intangible Assets of the Notes to the Consolidated Financial Statements for additional details.

•On May 30, 2025, we entered into a License and Unit Purchase Agreement with NEWLEVEL IV, L.P. and NEWLEVEL, LLC, both of which are affiliates of Grain Management, LLC (“Grain”), pursuant to which we will sell our 800 MHz spectrum licenses in exchange for cash consideration of $2.9 billion and the receipt of Grain’s 600 MHz spectrum licenses, which we are currently utilizing under lease agreements with Grain. See Note 7 – Goodwill, Spectrum License Transactions and Other Intangible Assets of the Notes to the Consolidated Financial Statements for additional details.

•We plan to evaluate future spectrum purchases in future auctions and secondary market opportunities to further augment or refine our current spectrum position.

•We have equipment deployed on macro cell sites and small cell/distributed antenna system sites across our network and leverage our CDC insights to optimize network positioning and performance.

Competition

The telecommunications industry remains competitive. We are the second largest provider of wireless communications services in the U.S. as measured by our total postpaid and prepaid customers. Our wireless communications services competitors include other carriers, such as AT&T Inc. (“AT&T”) and Verizon Communications, Inc. (“Verizon”). In addition, our wireless communications services competitors include numerous smaller and regional providers, including Charter Communications, Inc., Comcast Corporation, EchoStar Corporation (“EchoStar”), Cox Communications, Inc., and Altice USA, Inc., many of which offer no-contract, postpaid and prepaid service plans. Competitors also include providers who offer similar communication services, such as voice, messaging and data services, using alternative technologies. In addition to our wireless communications services, our broadband services compete against other broadband providers, including Cable, DSL and other Fiber broadband providers, other fixed wireless solutions, including AT&T and Verizon’s fixed wireless products, and satellite internet providers. Competitive factors within the telecommunications industry include promotions, pricing, market saturation, service and product offerings, customer experience, network investment and quality, development and deployment of technologies and changes in the regulatory environment that may affect market entry, pricing practices and network investment. Some of our competitors have shown a willingness to use discounted pricing or offer bundled services as a potential source of differentiation.

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Human Capital

Employees

As of December 31, 2025, we employed approximately 75,000 full-time and part-time employees, including network, retail, administrative and customer support functions.

Attraction and Retention

We employ a highly skilled workforce within a broad range of functions. Substantially all of our employees are located throughout the United States, including Puerto Rico, to serve our nationwide network and retail operations. Our headquarters are located in Bellevue, Washington, and Overland Park, Kansas.

We attract and retain our workforce through a dynamic and inclusive culture and by providing a comprehensive set of benefits, including:

•Competitive medical, dental and vision benefits;

•Family-building benefits designed to meet the various needs of our employees, including IVF and IUI, adoption and surrogacy benefits;

•Annual stock grants to all full-time and part-time employees and a discounted Employee Stock Purchase Program;

•A 401(k) Savings Plan;

•Nationwide minimum pay of at least $20 per hour to all full-time and part-time employees;

•LiveMagenta: a custom-branded program for employee engagement and well-being, including free access to life coaches, financial coaches and tools for healthy living;

•Access to personal health advocates offering independent guidance;

•A generous paid time off program, including paid family leave;

•Tuition assistance for all full-time and part-time employees, including full tuition partnerships with multiple schools; and

•A matching program for employee donations and volunteering.

Training and Development

Career growth and development is foundational to T-Mobile’s culture and success. We want to deliver the best experiences from the best teams, and one way we do that is by offering an array of development programs and resources to build talent and empower our people to succeed through every step of their career. We focus on helping employees understand the skills needed for their career success and give them access to learning in many forms, such as mentoring, training, structured learning programs, videos and books.

By strategically investing in the following three key areas of career development and learning, we are developing our talent now and for the future.

•Evolve skills and careers – from onboarding throughout careers, with clear expectations on contributions to the business and opportunities to develop and build their career;

•Advance leadership expertise – build critical leadership capabilities, enable leadership growth at all levels, and develop skills to lead in the future; and

•Enable effective collaboration – align with our values and behavioral norms, provide tools, resources, and learning needed for individual and team success.

Culture and Belonging

Our culture of belonging fosters trust, accelerates innovation, sparks new ideas and enhances collaboration. This fuels our success by enabling our employees to deliver exceptional experiences for our customers and to make a positive impact on the communities we serve. We aim to create an environment where employees have careers, not jobs, where everyone has a voice and belongs, and where leaders empower each employee to act like an owner and share in the Company’s success. T-Mobile’s hiring process casts a wide net to attract and hire the most qualified candidates.

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Employee Resource Groups

Our Employee Resource Groups (“ERGs”) play an important role in enhancing T-Mobile’s culture and providing valuable learning and development opportunities for our employees. Our six ERGs and four sub-affinity groups are open to all employees at the Company and are closely tied to our business goals and priorities. Our ERGs foster invaluable connections, community service and career development opportunities for employees. Many employees participate in the ERGs and the 38 chapters nationwide that organize volunteer opportunities and local events. Our chapter volunteers have led impactful initiatives and community service projects across the country for our employees.

Environmental Sustainability

Efficiencies and Reducing Our Carbon Footprint

We are actively working to identify efficiencies in our energy usage and reduce our environmental impact by:

•Pursuing a science-based net-zero emissions target for 2040, covering Scope 1, 2 and 3 emissions;

•Investing in renewable energy, meeting our RE100 pledge since 2021, through initiatives such as Virtual Power Purchasing Agreements and clean energy projects expected to produce over 3.4 million megawatt hours annually;

•Enhancing energy efficiency in our network and facilities, including retail stores, data centers, and cell sites; and

•Promoting a circular economy through a robust device reuse and recycling program.

Responsible Sourcing

We believe our suppliers are a valuable extension of our business and corporate values. Our Supplier Code of Conduct outlines expectations around ethical business practices for our suppliers. We require our suppliers to operate in compliance with the laws, rules, regulations and ethical standards of the countries in which they operate or provide products or services. We expect our suppliers to share our commitment to ethical conduct and environmentally responsible business practices while they conduct business with or on behalf of us. Our Responsible Sourcing Policy further outlines T-Mobile’s expectations in this area.

We employ a third-party risk management (“TPRM”) process to screen for anti-corruption, global sanctions, cybersecurity, human rights and environmental risks before engaging with a supplier. Our TPRM process also continuously monitors current suppliers for policy violations and risks.

Regulation

The FCC regulates many key aspects of our business, including licensing, construction, the operation and use of our network, modifications of our network, control and ownership of our licenses and authorizations, the sale, transfer and acquisition of certain licenses, domestic roaming arrangements and interconnection agreements, pursuant to its authority under the Communications Act of 1934, as amended (“Communications Act”). The FCC has a number of complex requirements that affect our operations and pending proceedings regarding additional or modified requirements that could increase our costs or diminish our revenues. For example, the FCC has rules regarding provision of 911, 988 and E-911 services, porting telephone numbers, interconnection, roaming, consumer broadband labels, robocalling/robotexting, disabilities access, privacy and cybersecurity, consumer protection and the universal service and Lifeline programs. Many of these and other issues are being considered in ongoing proceedings, and we cannot predict whether or how such actions will affect our business, financial condition or operating results. Our ability to provide services and generate revenues could be harmed by adverse regulatory action or changes to existing laws and regulations. In addition, regulation of companies that offer competing services can impact our business indirectly.

Except for operations in certain unlicensed frequency bands, wireless communications services providers generally must be licensed by the FCC to provide communications services at specified spectrum frequencies within specified geographic areas and must comply with the rules and policies governing the use of the spectrum as adopted by the FCC. The FCC issues each license for a fixed period of time, typically 10-15 years depending on the particular licenses. While the FCC has generally renewed licenses given to operating companies like us, the FCC has authority both to revoke a license for cause and to deny a license renewal if a renewal is not in the public interest. Furthermore, we could be subject to fines, forfeitures and other penalties for failure to comply with FCC regulations, even if any such noncompliance was unintentional. In extreme cases, penalties can include revocation of our licenses. The loss of any licenses, or any related fines or forfeitures, could adversely affect our business, financial condition and operating results. In addition, the FCC retains the right to modify rules related to use of licensed spectrum, which could impact T-Mobile’s ability to provide services.

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Additionally, Congress’s and the FCC’s allocation of additional spectrum for broadband commercial mobile radio service (“CMRS”), which includes cellular, PCS and other wireless services, could significantly increase and intensify competition. We cannot assess the impact that any developments that may occur in the U.S. economy or any future spectrum allocations by the FCC may have on license values. FCC spectrum auctions and other market developments may adversely affect the market value of our licenses or our competitive position in the future. A significant decline in the value of our licenses could adversely affect our financial condition and operating results. In addition, the FCC periodically reviews its policies on how to evaluate carriers’ spectrum holdings in the context of spectrum transactions or acquisitions. Changes in these rules and policies could affect our access to additional spectrum resources and competition among us and other carriers.

Congress and the FCC have imposed limitations on foreign ownership of CMRS licensees. Direct foreign ownership in the licensee of more than 20% is prohibited. Indirect foreign ownership of more than 25% through an entity controlling the licensee must be reviewed and approved by the FCC as not inconsistent with the public interest. Consistent with that established policy, the FCC has issued a declaratory ruling authorizing up to 100% ownership of our Company by DT.

For our Educational Broadband Service (“EBS”) licenses in the 2.5 GHz band, FCC rules previously limited eligibility to hold EBS licenses to accredited educational institutions and certain governmental, religious and nonprofit entities, while permitting those license holders to lease their licenses to commercial providers for non-educational purposes. Therefore, we have historically accessed EBS spectrum primarily through long-term leasing arrangements with EBS license holders. Our EBS spectrum leases typically have an initial term equal to the remaining term of the EBS license, with an option to renew the lease for additional terms, for a total lease term of up to 30 years. In April 2020, the FCC lifted the restriction on who can hold EBS licenses and the 30-year limitation on lease duration, among other changes. The elimination of these restrictions allows current license holders to sell their licenses, including to T-Mobile. While a majority of our leases have contractual provisions enabling us to match offers, we may be forced to compete with others to purchase 2.5 GHz licenses on the secondary market and expend additional capital earlier than we may have anticipated. T-Mobile has started to acquire some of these EBS licenses, but we continue to lease spectrum in this band and expect that to be the case for some time.

While the Communications Act generally preempts state and local governments from regulating the entry of, or the rates charged by, wireless communications services providers, certain state and local governments regulate other terms and conditions of wireless service, including billing, termination of service arrangements and the imposition of early termination fees, advertising, network outages, the use of devices while driving, service mapping, protection of consumer information, zoning and land use. Notwithstanding this federal preemption, several states are considering or have passed laws or regulations that could potentially set prices, minimum performance standards and/or restrictions on service discontinuation that could impact our business in those states.

For example, California has passed separate privacy and net neutrality legislation, while many others have passed privacy laws, and New York has passed a broadband rate-setting law. There are also efforts within Congress to pass federal legislation to codify uniform federal privacy and net neutrality requirements. Ensuring the preemption of separate state requirements, including the California laws, is critical to this effort. If not preempted or rescinded, separate state requirements will impose significant business costs and could also result in increased litigation costs and enforcement risks. A number of states also subject wireless service providers to registration requirements. State authority over wireless broadband services will likely remain unsettled unless resolved by the courts, the FCC or Congress.

In addition, the Federal Trade Commission (“FTC”) and other federal agencies have jurisdiction over some consumer protection matters and the elimination and prevention of anticompetitive business practices with respect to the provision of non-common carrier services. Further, the FCC and the Federal Aviation Administration regulate the siting, lighting and construction of transmitter towers and antennae. Tower siting and construction are also subject to state and local zoning, as well as federal statutes regarding environmental and historic preservation. The future costs to comply with all relevant regulations are, to some extent, unknown, and changes to regulations, or the applicability of regulations, could result in higher operating and capital expenses, or reduced revenues in the future.

We have pursued and may continue to pursue acquisitions of, investments in, or joint ventures or mergers with, other companies that we believe would complement or expand our business. To the extent any such business has any international operations, we may be subject to economic, tax and labor regulations in these international jurisdictions.

Available Information

The SEC maintains an internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically at www.sec.gov. Our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities

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Exchange Act of 1934, as amended (the “Exchange Act”) are also publicly available free of charge on the investor relations section of our website at investor.t-mobile.com as soon as reasonably practicable after they are electronically filed with or furnished to the SEC. Our corporate governance guidelines, director selection guideline, code of ethics for senior financial officers, code of business conduct, speak up policy, supplier code of conduct, and charters for the audit committee, compensation committee, nominating, corporate governance and compliance committee, and executive committee of our Board of Directors are also posted on the investor relations section of our website at investor.t-mobile.com. The information on our website is not part of this or any other report we file with, or furnish to, the SEC.

Item 1A. Risk Factors

In addition to the other information contained in this Form 10-K, the following risk factors should be considered carefully in evaluating T-Mobile. Our business, financial condition, liquidity, or operating results, as well as the price of our common stock and other securities, could be materially and adversely affected by any of these risks.

Risks Related to Our Business

We operate in a highly competitive industry. If we are unable to attract and retain customers, our business, financial condition, and operating results could be negatively affected.

The telecommunications industry is highly competitive. As the industry reaches saturation, competition in all market segments, including prepaid, postpaid, enterprise and government customers will likely further intensify, putting pressure on pricing and/or margins for us and all our competitors. Our ability to attract and retain customers will depend on multiple factors, such as network quality and capacity, customer service excellence, effective marketing strategies, competitive pricing, compelling value propositions, and distribution and logistics capabilities. Additionally, targeted marketing approaches for a broad spectrum of customer segments, coupled with continuous innovation in products and services, are essential for retaining and expanding our customer base. If we are unable to successfully differentiate our services from those of our competitors, it would adversely affect our competitive position and ability to grow our business.

We expect to continue to see intense competition in all market segments from traditional Mobile Network Operators (“MNOs”), such as AT&T and Verizon, who have each invested heavily in spectrum, their wireless networks, and services and device promotions. Numerous other regional MNOs and MVNOs offering wireless services may also compete with us in some markets, including cable providers, such as Comcast, Charter, Cox, and Altice, as they continue to diversify their offerings to include wireless services offered under MVNO agreements. As new products and services emerge, we may also face competition from non-traditional competitors outside the wireless communications services industry, including satellite providers offering connectivity services using alternative technologies.

In the market for broadband services, traditional cable providers, AT&T, Verizon, and other players such as satellite and fiber providers, all compete for customers. To complement our fixed wireless service, we have entered into joint venture agreements aimed at establishing a robust fiber wireline network in certain geographic regions that we believe will complement our fixed wireless services in those areas. However, these partnerships also involve inherent risks. See “Any acquisition, investment, joint venture, merger, or divestiture may subject us to significant risks, any of which may harm our business” for further discussion of such risks.

If we are unable to compete effectively in attracting and retaining customers in markets where we operate, it could negatively affect our business, financial condition, and operating results.

We have experienced cyberattacks and may experience disruptions, data loss and other security breaches, whether directly or indirectly through third parties whose products and services we rely on in operating our business.

Our business involves the receipt, storage, and transmission of confidential information about our customers, such as sensitive personal, account, and payment information, confidential information about our employees and suppliers, and other sensitive information about our Company, such as our business plans, transactions, financial information, and intellectual property (collectively, “Confidential Information”). Additionally, to offer services to our customers and operate our business, we utilize several applications and systems, including those we own and operate, such as our wireless network, as well as others provided to us by third parties, such as cloud service providers and SaaS companies (collectively, “Systems”).

We are subject to persistent cyberattacks and threats to our business from bad actors seeking to gain unauthorized access to Confidential Information and compromise Systems to undermine availability or integrity. They are perpetrated by a variety of

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groups and persons, including nation state-sponsored parties, malicious actors, employees, contractors, and other third parties. Some actors reside in jurisdictions where law enforcement measures to address such attacks are ineffective or unavailable.

Cyberattacks against companies like ours are increasing in frequency and scope of potential harm over time, and the methods used to gain unauthorized access constantly evolve, making it increasingly difficult to anticipate, prevent, and detect incidents successfully in every instance. In some cases, these bad actors exploit bugs, errors, misconfigurations or other vulnerabilities in our Systems to obtain Confidential Information. In other cases, these bad actors obtain unauthorized access to Confidential Information by exploiting insider access or utilizing login credentials taken from our customers, employees, or third-party providers through credential harvesting, social engineering or other means. Other bad actors aim to cause serious operational disruptions to our business and Systems through ransomware or distributed denial of service attacks. Moreover, the amount and scope of insurance that we maintain against losses resulting from any such incidents or security breaches may not be sufficient to cover our losses or otherwise adequately compensate us for any disruptions to our business that may result.

Although we regularly work to identify, track, and remedy security vulnerabilities, given the complex nature of our Systems and the tools that are available to us, we may be unable to identify vulnerabilities in a timely manner, or to apply patches or compensating measures that address such vulnerabilities, before bad actors can exploit them. The exploitation of a security vulnerability before patches or measures are applied could materially compromise Confidential Information and Systems.

In addition, we routinely rely upon third-party providers whose products and services are used in our business. These third-party providers have experienced, and will continue to experience, cyberattacks that involve attempts to access our Confidential Information and/or to create operational risk that could materially and adversely affect our business, and these providers also face other security challenges common to all parties that collect and process information. Additionally, our Systems include components from third parties or fourth parties we do not control and may have compromises, defects, flaws, or design errors unknown to us.

As a result of the previously disclosed cyberattacks in August 2021 and January 2023, we incurred significant costs in connection with, among other things, responding to and resolving mass arbitration claims, multiple class action lawsuits, and an FCC investigation. For more information on the foregoing, see “– Contingencies and Litigation – Litigation and Regulatory Matters” in Note 18 – Commitments and Contingencies of the Notes to the Consolidated Financial Statements.

In addition to the August 2021 cyberattack and the January 2023 cyberattack, we have experienced unrelated, non-material incidents involving unauthorized access to certain Confidential Information and Systems. Typically, these incidents have involved attempts to commit fraud by taking control of a customer’s phone line, often by exploiting insider access or using compromised credentials. In other cases, the incidents have involved unauthorized access to certain of our customers’ private information, including payment information, financial data, social security numbers or passwords, and our intellectual property. Some of these incidents have occurred at third-party providers, including third parties who provide us with various Systems and others who sell our products and services through retail locations or take care of our customers.

Our procedures and safeguards to prevent unauthorized access to Confidential Information and to defend against cyberattacks seeking to disrupt our operations must be continually evaluated and enhanced to address the ever-evolving threat landscape and changing cybersecurity regulations, including while we adapt complex digital transformation efforts. These preventative actions require the investment of significant resources and management time and attention. Additionally, we do not have control of the cybersecurity systems, breach prevention, and response protocols of our third-party providers, including through our cybersecurity programs or policies. While T-Mobile may have contractual rights to assess the effectiveness of many of our providers’ systems and protocols, we do not have the means to always know or assess the effectiveness of all of our providers’ systems and controls. We cannot provide any assurances that actions taken by us, or our third-party providers, including through our cybersecurity programs or policies, will adequately repel a significant cyberattack or prevent or substantially mitigate the impacts of cybersecurity breaches or misuses of Confidential Information, unauthorized access to our networks or Systems or exploits against third-party environments, or that we, or our third-party providers, will be able to effectively identify, investigate, and remediate such incidents in a timely manner or at all. We expect to continue to be the target of cyberattacks, given the nature of our business, and we expect the same with respect to our third-party providers. We also expect that threat actors will continue to gain sophistication including in the use of tools and techniques (such as AI) that are specifically designed to circumvent security controls, evade detection, and obfuscate forensic evidence, making it more challenging to identify, investigate, and recover from future cyberattacks in a timely and effective manner. The continued development and integration of AI in our and our third-party providers’ operations, products and services is expected to pose new, additional, and unknown cybersecurity risks. In addition, we have acquired and continue to acquire companies with cybersecurity vulnerabilities or unsophisticated security measures, which expose us to significant cybersecurity, operational, and financial risks. If we fail to protect Confidential Information or to prevent operational disruptions from future cyberattacks, there may be a material adverse effect on our business, reputation, financial condition, cash flows, and operating results.

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If we fail to adopt and deploy emerging network technologies in a timely and effective manner, our competitive position could erode, which may adversely affect our business, financial condition, and operating results.

Our competitive advantage and reputation depend on our ability to provide industry-leading network coverage, speed, and reliability. While we have established a leadership position in 5G, the telecommunications industry evolves rapidly, and emerging technologies, such as AI-driven Radio Access Networks (“AI-RAN”) and the potential transition to 6G, may redefine network standards and increase customer expectations. Our competitors may seek to differentiate through marketing, brand positioning, or third-party recognition as leaders in network performance, coverage, or reliability. To stay ahead, we continue to drive improvements in the 5G network, including our nationwide 5G standalone network and deployment of 5G Advanced features, and are investing in strategic collaborations with third parties, such as AI-RAN partnerships, to develop technologies that are intended to advance our network capabilities. Despite these efforts, we may encounter technical challenges, regulatory hurdles, supply chain constraints, or unexpected delays in developing and deploying new network technologies. If we fail to anticipate market trends, efficiently integrate innovative solutions into our network, or maintain the quality and reliability of our network, our market share and competitive standing could erode, adversely affecting our business, financial condition, and operating results.

If we fail to effectively execute our digital transformation and drive customer and employee adoption of emerging technologies, our competitive position and financial performance could be materially harmed.

We are engaged in complex digital transformation efforts intended to streamline operations, enhance customer experience, and improve our overall competitiveness. These initiatives involve integrating emerging and rapidly evolving technologies, reconfiguring internal processes, and implementing advanced data analytics and AI-driven tools, including those developed through our partnerships with several third-party providers. The successful execution of our planned transformation is subject to significant uncertainties. For example, we may face challenges in harmonizing complex system architectures, integrating new platforms with legacy infrastructure, and managing large volumes of data from disparate sources. We must also maintain rigorous data security and privacy safeguards, ensure our AI-driven solutions comply with evolving regulatory standards, and mitigate potential issues such as algorithmic bias or unintended operational disruptions. Additionally, implementing these digital solutions often requires substantial capital and operational expenditures, extensive employee training, specialized skill sets that may be difficult to source, and close coordination with multiple third-party vendors and partners. If we fail to execute these initiatives effectively, our ability to realize the intended benefits of digital transformation may be compromised.

The successful execution of our digital transformation depends not only on the effective development and deployment of new technologies, but also on the willingness and ability of customers and employees to adopt digital-first channels and processes. Even where technical capabilities are successfully implemented, customer and employee adoption may lag expectations or revert to supported channels, which could limit the anticipated improvements in efficiency, service quality, and revenue generation. If adoption does not occur at the scale or pace anticipated, the intended benefits of these initiatives may not be fully realized.

As a result, failure to effectively execute our digital transformation efforts, including driving meaningful customer and employee adoption, could materially and adversely affect our competitive position, financial performance, and brand reputation.

We rely on highly skilled personnel throughout all levels of our business. Our business could be harmed if we are unable to retain or motivate key personnel, hire a sufficient number of qualified new personnel, or maintain our corporate culture.

Our future success depends in substantial part on our ability to attract, recruit, hire, motivate, develop, and retain talented personnel possessing the qualifications, experience, capabilities and skills we need for all areas of our organization, including our CEO and members of our leadership team. Succession planning to ensure the effective transfer of knowledge and a seamless transition when key personnel depart is also important to our long-term success. On November 1, 2025, G. Michael Sievert retired as our Chief Executive Officer while continuing to serve as Vice Chairman of the Company and Vice Chairman of our Board of Directors, and Srinivasan Gopalan began serving as our President and Chief Executive Officer. We also announced several leadership changes. In addition, we began to implement enterprise-wide restructurings in 2025. If we are unable to effectively manage the CEO transition, the leadership changes and other restructuring changes, our ability to execute our business strategies and to retain key executives and talent could be adversely affected. Additionally, as we continue to make significant investments in new technologies and new business areas, we are increasingly dependent on being able to hire and retain technically skilled employees, including those with expertise in AI and machine learning.

Both external factors, such as fluctuations in economic and industry conditions, changes in U.S. immigration policies, regulatory changes, political forces, and the competitive landscape, and internal factors, such as employee tolerance for changes

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in our corporate culture, organizational changes, limited remote working opportunities, and our compensation programs, may affect our ability to effectively manage our workforce. Further, employee compensation and benefit costs may increase due to inflationary pressures, and if our compensation does not keep up with inflation or with that of our competitors, we may see increased employee dissatisfaction and departures or difficulty in recruiting new employees. If key employees depart or we are unable to recruit and integrate new employees successfully, our business could be negatively impacted.

System failures and business disruptions may prevent us from providing reliable service, which could materially and adversely affect our reputation and financial condition.

We rely upon systems and networks – those of third-party suppliers and other providers, in addition to our own – to provide services to our customers. System, network, or infrastructure failures resulting from one of several potential causes may prevent us from providing reliable service or otherwise operating our business. Examples of these risks include:

•physical damage, power surges or outages, equipment failure, or other service disruptions with respect to both our wireless and fiber networks, including those resulting from severe weather, storms, earthquakes, floods, hurricanes, wildfires, and other natural disasters, which may occur more frequently or with greater intensity as a result of global climate change, public health crises, terrorist attacks, political instability and volatility and acts of war;

•human error due to factors such as poor change management or policy compliance;

•risks to our access to and use of reliable energy and water;

•hardware or software failures or outages of our business systems or communications network;

•supplier failures or delays; and

•shifts in physical conditions due to climate change, such as sea-level rise or changes in temperature or precipitation patterns, which may impact the operating conditions of our infrastructure or other infrastructure we rely on.

Such events could cause us to lose customers and revenue, incur expenses, suffer reputational damage, and subject us to fines, penalties, adverse actions or judgments, litigation, or governmental investigations. Remediation costs could include liability for information loss, costs of repairing infrastructure and systems, and/or costs of incentives offered to customers. Our insurance may not cover or may not be adequate to fully reimburse us for costs and losses associated with such events, and such events may also impact the availability of insurance at costs and other terms we find acceptable for future events.

The scarcity and cost of additional wireless spectrum, and regulations relating to spectrum use, may adversely affect our business, financial condition, and operating results.

We continue to acquire and deploy new spectrum to expand and deepen our 5G coverage, maintain our quality of service, meet increasing or changing customer demands, and deploy new technologies. To expand and differentiate our services from those of our competitors, we will continue to actively seek to make additional investments in new spectrum, which could be significant. However, we may be unable to secure the additional spectrum necessary to maintain or enhance our competitive position on favorable terms or at all.

The continued interest in acquiring spectrum by existing carriers and others, including satellite providers and speculators, may reduce our ability to acquire or renew spectrum holdings (such as 600 MHz and 2.5 GHz), and may increase the cost of spectrum made available in the secondary markets and government auctions. Additionally, the FCC may be unable to make sufficient additional spectrum available for auction to meet the demand from all interested parties. As a result, any such spectrum that is made available at auction may be subject to heightened competition and priced beyond levels we are able or willing to pay.

Even if new spectrum becomes available to us, the FCC or other government entities may impose conditions on the acquisition and use of such spectrum, such as the configuration or geographic areas in which the spectrum may be deployed. These conditions may substantially increase the costs we incur or negatively affect the value of the spectrum to our business.

If we cannot acquire needed spectrum from the government or other sources, if competitors acquire spectrum that enables them to provide services competitive with ours, or if we cannot deploy services over acquired spectrum on a timely basis, without burdensome conditions, at reasonable cost, and while maintaining network quality levels, our ability to attract and retain customers and our business, financial condition, and operating results could be materially and adversely affected.

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Any acquisition, investment, joint venture, merger, or divestiture may subject us to significant risks, any of which may harm our business.

We have pursued and may continue to pursue additional acquisitions of, investments in, or joint ventures or mergers with, other companies, or the acquisition of spectrum, technologies, services, products, or other assets that we believe would complement or expand our business. For example, on August 1, 2025, we completed the acquisition (the “UScellular Acquisition”) of the UScellular Wireless Business (as defined below). We may also elect to divest some of our assets to third parties. Some of these transactions could be significant relative to the size of our business and operations. Any such transactions involve risks and could present financial, managerial, and operational challenges, including:

•diversion of management attention from running our existing business;

•increased costs to integrate the networks, spectrum, technology, personnel, customer base, distributors and business partners and business practices of the company involved in any such transaction with our business;

•increased interest expense and leverage or limits on other uses of cash;

•potential loss of talent during integration due to differences in culture, location, or other factors;

•difficulties in effectively integrating (or supplanting) the financial, operational, and sustainability systems of the business involved in any such transaction into our financial, operational, and sustainability reporting infrastructure and internal control framework in an effective and timely manner;

•risks of entering markets in which we have no or limited experience and where competitors have stronger market positions;

•to the extent any acquired business has international operations, potential exposures to risks associated with maintaining and expanding such operations, including unfavorable and uncertain regulatory, political, economic, tax, and labor conditions;

•potential exposure to material liabilities not discovered in the due diligence process in connection with any such transaction;

•significant transaction-related expenses in connection with pursuing any such transaction, whether consummated or not;

•risks related to our ability to obtain required regulatory approvals necessary to consummate any such transaction; and

•any business, technology, service, or product involved in any such transaction may significantly underperform relative to our expectations, and we may not achieve the benefits we expect from the transaction, which could also result in a write-down of goodwill and other intangible assets associated with such transaction.

Our restructuring and integration activities associated with the UScellular Acquisition are expected to occur over the next two years and may involve risks related to network integration and customer migration, including potential service disruptions, delays in transitioning customer accounts and systems, and challenges in maintaining customer experience during the integration period.

We formed joint ventures aimed at establishing fiber broadband networks that complement our fixed wireless services. Differences in views among the joint venture participants may result in delayed decisions or disputes. Operating through joint ventures in which we do not hold a majority or controlling ownership interest results in us having limited control over many decisions made with respect to the businesses of the joint ventures. We also cannot control the actions of our co-investors in our joint ventures. These joint ventures may not be subject to the same requirements regarding internal controls and internal control over financial reporting that we follow. As a result, internal control problems may arise with respect to these joint ventures. Any of these risks could have a material adverse effect on our business, financial condition, and operating results and could also affect our reputation.

Additionally, in connection with our merger (the “Sprint Merger”) with Sprint Corporation (“Sprint”) and related transactions, including the acquisition by DISH Network Corporation (“DISH”) of certain prepaid wireless business (the “Prepaid Transaction”), we agreed to fulfill various government commitments (the “Government Commitments”), including, among others, extensive 5G network build-out, delivering high-speed wireless services to the vast majority of Americans, and marketing our in-home fixed wireless product to households where spectrum capacity is sufficient, as well as commitments related to national security. These Government Commitments materially increased our compliance obligations and could result in additional expenses and/or penalties in the future.

Any failure to fulfill our obligations under the Government Commitments in a timely manner could result in substantial fines, penalties, or other legal and administrative actions, liabilities, and reputational harm.

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Economic, political, and market conditions may adversely affect our business, financial condition, and operating results.

Our business, financial condition, and operating results are affected by changes in general economic and political conditions, including interest rates, consumer credit conditions, consumer debt levels, consumer confidence, unemployment rates, economic growth, tariffs and trade restrictions, fluctuations in global currencies, immigration policies, energy costs, rates of inflation (or concerns about deflation), supply chain disruptions, impacts of current geopolitical conflict or instability, such as the Ukraine-Russia and Israel-Hamas wars and any further escalations thereof, and other macroeconomic factors.

The telecommunications industry, broadly, is dependent on population growth, including growth in the immigrant population. As a result, we expect the telecommunications industry’s customer growth rate to be moderate in comparison with historical growth rates, leading to ongoing competition for customers. Rising prices for goods, services, and labor due to inflation, including inflation resulting from higher tariffs, restrictions, and other economic disincentives to trade, could adversely impact our margins and growth.

Our services and device financing plans are available to a broad customer base, a significant segment of which may be vulnerable to weak economic conditions, particularly our subprime customers. We may have greater difficulty in gaining new customers within this segment, and existing customers may be more likely to terminate service and default on device financing plans due to an inability to pay.

Weak economic and credit conditions may also adversely affect our suppliers, dealers, wholesale partners or MVNOs, and enterprise and government customers, some of which may file for bankruptcy, or may experience cash flow or liquidity problems, or may be unable to obtain or refinance credit such that they may no longer be able to operate. Any of these could adversely impact our ability to distribute, market, or sell our products and services.

Changes to trade policies, including higher tariffs, restrictions, and other economic disincentives to trade, may lead to operational delays, higher procurement and operational costs, and increased regulatory and compliance complexities, resulting in supply chain disruptions and higher prices, and lower demand for devices and services we sell.

As a provider of telecommunications services, we depend on suppliers to provide us, directly or through other suppliers, with items such as equipment for our network, handsets, tablets, accessories, other mobile communication devices, other components and raw materials. Changes or proposed changes in U.S. or other countries’ trade policies that result in higher tariffs, restrictions, and other economic disincentives to international trade have occurred in the past, and in the future may occur, which may materially increase the costs we incur in developing, deploying and maintaining our network and offering products and services to our customers. A certain portion of the increased costs may be absorbed by certain suppliers, but some suppliers may struggle to absorb the increased costs, especially over the long term, potentially leading to supply disruptions or cost pass-throughs to us that may require us to increase the prices we charge our customers. In addition, rapid changes in trade policies may negatively affect procurement timelines and supplier relationships and may introduce new compliance requirements. We may face delays in sourcing critical equipment due to customs clearance and supply chain bottlenecks, and material changes to cost structures could pressure our expenses and customer pricing.

Our attempts to mitigate potential disruptions to our supply chain and offset procurement and operational cost pressures, such as through alternative sourcing and/or increases in the selling prices of some of our products and services, may not be successful. Higher product or service prices for our customers may make it more difficult to attract new customers or increase customer churn. Furthermore, we may not be able to offset any cost increases through productivity and cost-saving initiatives. To the extent that cost increases result in significant increases in our expenditures, or if our price increases are not sufficient to offset these increased costs adequately or in a timely manner, and/or if our revenues decrease, our business, financial condition or operating results may be adversely affected.

If we do not successfully deliver new products and services, we may not realize our intended growth targets or generate the expected returns from our business, adversely affecting our financial condition and operating results.

We continue to expand our offerings beyond traditional wireless services to include broadband (fixed wireless and fiber), specialized network solutions, such as network slicing for first responders (“T-Priority”) and 5G advanced network solutions (“ANS”) for enterprises, advertising technology and services, and financial products, such as the T-Mobile Visa credit card introduced in November 2025. These new ventures require significant capital, expertise, and operational support, and their success depends on factors we cannot fully control or predict. Increased competition, technical challenges, security concerns, operational complexities, or shifting regulatory landscapes could delay product rollouts, inflate costs, or limit adoption rates. Additionally, entering new markets or lines of business may expose us to unfamiliar regulatory requirements, compliance challenges, or risks to existing customer relationships. Customer demand for new products and services is difficult to predict,

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and adoption may be slower than anticipated or may not occur at all. Should these new products and services fail to gain traction, achieve sufficient customer adoption, generate expected financial returns, or deliver value to customers, we could incur substantial expenses without offsetting revenue gains, adversely affecting our business, financial condition, operating results and competitive position.

We rely on third parties to provide products and services for the operation of our business, and the failure or inability of such parties to provide these products or services could adversely affect our business, financial condition, and operating results.

We have a broad set of suppliers to help us develop, maintain, and troubleshoot products and services such as wireless and fiber network components, software development services, and billing and customer service support. However, in certain areas such as billing services, voice, and data communications transport services, wireless or fiber network infrastructure equipment, handsets, other devices, back-office processes, and payment processing, there are a limited number of suppliers that can provide adequate support, which decreases our flexibility to switch to alternative third parties. Unexpected termination of our arrangement with any of these suppliers, or difficulties in renewing our commercial arrangements with them, could have a material adverse effect on our business operations.

Our suppliers and third-party technology partners are also subject to their own risks, including, but not limited to, cybersecurity, economic, financial and credit conditions, labor force disruptions, geopolitical tensions, disruptions in global supply chain, natural catastrophic events, such as earthquakes, floods, hurricanes, storms, heatwaves and fires, energy shortages, power outages, equipment failures, terrorist attacks or other hostile acts, and public health crises, such as the COVID-19 pandemic. These events may result in performance below the levels required by their contracts or cause them to suspend, limit, or cease their operations, or terminate or reduce their relationship with us. We could experience severe business disruptions and delays in technology initiatives if critical suppliers or service providers fail to comply with their contracts, if we experience delays or service degradation during any transition to a new outsourcing provider or other supplier, or if we are required to replace the supplied products or services with those from another source, especially if the replacement becomes necessary on short notice. Any such disruptions could have a material adverse effect on our business, financial condition, and operating results.

Further, some of our suppliers may provide services from outside the United States, which carries additional regulatory and legal obligations. We rely on suppliers to provide us with contractual assurances and to disclose accurate information regarding risks associated with their provision of products or services in accordance with our policies and standards, including our Supplier Code of Conduct and our third-party risk management practices. The failure of our suppliers to comply with our expectations and policies could expose us to additional legal and litigation risks and lead to unexpected contract terminations.

Sociopolitical volatility and polarization may adversely affect our business operations and reputation.

The current sociopolitical environment is characterized by deep complexity, volatility, and polarization on various social and political issues. The increasing intersection of technology and politics has led to rapid and unpredictable shifts in public sentiment. Social media and digital platforms have amplified the voices of various stakeholders, creating the potential for swift change in public opinion and stronger reactions to corporate actions. As a company that sells products and services across the nation to millions of customers, these dynamics increase the risk of potential reputational damage, boycotts, and shifts in consumer behavior that could adversely affect our brand, sales, and profitability. Our ability to respond effectively, sensitively, and authentically to the expectations and concerns of our customers, employees, and other stakeholders is key to mitigating these risks. If we are unable to manage these challenges effectively, there may be adverse impacts on our business, reputation, financial condition, and operating results.

Additionally, we are subject to emerging and evolving regulatory requirements and frameworks regarding environmental, social and governance matters, including recently enacted or proposed legislation in jurisdictions such as California. The ultimate scope of these regulations may change as they are finalized, and they may not be uniform across jurisdictions. Meeting these obligations may require significant investments of time, capital, and personnel.

Risks Related to Our Indebtedness

Our substantial level of indebtedness could adversely affect our business flexibility and ability to service our debt and could increase our borrowing costs.

We have, and we expect that we will continue to have, a substantial amount of debt. Our substantial level of indebtedness could have the effect of, among other things, reducing our flexibility in responding to changing business, economic, market, and industry conditions and increasing the amount of cash required to service our debt. In addition, this level of indebtedness may

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also reduce funds available for capital expenditures, any Board-approved share repurchases, dividends, or other activities. Those impacts may put us at a competitive disadvantage relative to other companies with lower debt levels. Further, we may incur substantial additional indebtedness in the future, subject to the restrictions contained in our debt instruments, if any, which could increase the risks associated with our capital structure.

Our ability to service our substantial debt obligations will depend on future performance, which will be affected by business, economic, market, and industry conditions and other factors. There is no guarantee that we will be able to generate sufficient cash flow to service our debt obligations when due. If we are unable to meet such obligations or fail to comply with the financial and other restrictive covenants contained in the agreements governing such debt obligations, we may be required to refinance all or part of our debt, sell important strategic assets at unfavorable prices, or make additional borrowings. We may not be able to, at any given time, refinance our debt, sell assets, or make additional borrowings on commercially reasonable terms or at all, which could have a material adverse effect on our business, financial condition, and operating results.

Changes in credit market conditions and other factors could adversely affect our ability to raise debt favorably.

Instability in the global financial markets, inflation, policies of various governmental and regulatory agencies, including changes in monetary policy and interest rates, and other general economic conditions could lead to volatility in the credit and equity markets. This volatility could limit our access to the capital markets, leading to higher borrowing costs or, in some cases, an inability to obtain financing on terms that are acceptable to us or at all. Further, deterioration in our operating performance may lead to a decrease in our credit ratings, which could also impact our ability to access the debt capital markets at rates favorable or acceptable to us.

In addition, any hedging agreements we may enter into to limit our exposure to interest rate increases or foreign currency fluctuations may not offer complete protection from these risks or may be unsuccessful, and consequently may effectively increase the interest rate we pay on our debt or the exchange rate with respect to any debt we may incur in a foreign currency, and any portion not subject to such hedging agreements would have full exposure to interest rate increases or foreign currency fluctuations, as applicable. If any financial institutions that are parties to our hedging agreements were to default on their payment obligations to us, declare bankruptcy or become insolvent, we would be unhedged against the underlying exposures. Any posting of collateral by us under our hedging agreements and the modification or termination of any of our hedging agreements could negatively affect our liquidity or other financial metrics. Any of these risks could have a material adverse effect on our business, financial condition, and operating results.

Risks Related to Legal and Regulatory Matters

Failure to maintain effective internal control over financial reporting could impair our compliance with Section 404 of the Sarbanes-Oxley Act, which could lead to material misstatements in our financial statements and adversely affect our operations and reputation.

We rely on robust internal controls to provide reasonable assurance regarding the reliability of our financial information and the preparation of our financial statements. These controls include, among other things, properly designed processes, clear policies and procedures, competent personnel, effective oversight functions, and reliable information systems that facilitate the collection, processing, and communication of financial data. As we continue to refine and improve our systems to align with our evolving business needs, there is no assurance that these improvements will be implemented without delays or disruptions. A failure or significant delay in updating our systems, or a failure to effectively integrate new systems with existing processes, could compromise the effectiveness of our internal controls. If our internal controls are not effectively designed or properly implemented, or if changes to our business processes or organizational structure outpace our internal controls’ ability to adapt, we could experience material weaknesses or other deficiencies.

Any material weaknesses or other control deficiencies that may arise in the future could require significant time and resources to remediate. If we are unable to remediate material weaknesses in internal control over financial reporting, then our ability to analyze, record and report financial information free of material misstatements, to prepare financial statements within the time periods specified by the rules and forms of the SEC and otherwise to comply with the requirements of Section 404 of the Sarbanes-Oxley Act would be negatively impacted. As a result, we could face legal fines and penalties, diminished investor confidence, and adverse impacts on our access to the capital markets, potentially resulting in a decline in our stock price and harm to our reputation.

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Compliance with the current regulatory framework, including our national security obligations, and any changes in regulations or in the regulatory framework under which we operate could adversely affect our business, financial condition, and operating results.

We are subject to regulatory oversight by various federal, state, and local agencies, as well as judicial review and actions, on issues related to the telecommunications industry that include, but are not limited to, roaming, interconnection, spectrum allocation and licensing, facilities siting, pole attachments, intercarrier compensation, Universal Service Fund (“USF”), 911 services, robocalling/robotexting, consumer protection, consumer privacy, and cybersecurity. We are also subject to regulations in connection with other aspects of our business, including device financing and insurance activities.

The FCC regulates the licensing, construction, modification, operation, ownership, sale, and interconnection of wireless communications systems, as do some state and local regulatory agencies. In particular, the FCC imposes significant regulation on licensees of wireless spectrum with respect to how radio spectrum is used by licensees or at what power levels, the nature of the services that licensees may offer and how the services may be offered, and the resolution of issues of interference between operators in the same or adjacent spectrum bands. Changes necessary to resolve interference issues or concerns may have a significant impact on our ability to fully utilize our spectrum. Additionally, the FTC and other federal and state agencies have asserted that they have jurisdiction over some consumer protection matters, and the elimination and prevention of anticompetitive business practices with respect to the provision of wireless products and services.

We cannot assure that the FCC or any other federal, state, or local agencies will not adopt or change regulations, change or discontinue existing programs, implement new programs, or take enforcement or other actions that would adversely affect our business, impose new costs, or require changes in current or planned operations, including timing of the shutdown of legacy technologies.

We also face potential investigations by, and inquiries from or actions by state public utility commissions. We also cannot assure that Congress will not amend the Communications Act, from which the FCC obtains its authority, and which serves to limit state authority, or enact other legislation in a manner that could be adverse to our business.

Failure to comply with applicable regulations could have a material adverse effect on our business, financial condition, and operating results. We could be subject to fines, forfeitures, and other penalties (including, in extreme cases, revocation of our spectrum licenses) for failure to comply with the FCC or other governmental regulations, even if any such noncompliance was unintentional. The loss of any licenses, or any related fines or forfeitures, could adversely affect our business, financial condition, and operating results.

In addition, we operate under agreements with U.S. government agencies, including a mitigation agreement with the Committee on Foreign Investment in the United States, under which we are required to implement and maintain certain security measures and practices to address national security. Our national security obligations may limit our control over certain U.S. facilities, contracts, personnel, vendor selection, and operations, which could adversely affect our business, financial condition, and operating results. Any failure to fulfill our obligations could result in additional compliance cost, substantial fines, penalties, or other legal and administrative actions, liabilities, and reputational harm.

Laws and regulations relating to the handling of privacy, data protection, and AI may result in increased costs, legal claims, fines, or reputational damage.

Since 2020, more than a dozen states have enacted new, comprehensive privacy laws that create new data privacy rights for residents of those states and new compliance obligations for us and the industry in general, in addition to private rights of action for certain types of data breaches. These include the California Consumer Privacy Act (“CCPA”) and similar laws in other states. Pending legislation in a number of other states would create similar laws elsewhere. All of these new privacy laws and others that we expect to be developed and enacted going forward will impose additional data protection obligations and potential liability on companies such as ours doing business in those states. Further, privacy laws also limit our ability to collect and use personal information.

We have incurred and will continue to incur significant implementation costs to ensure compliance with the CCPA, new privacy laws in other states, and their related regulations, including managing the complexity of laws that vary from state to state. Both federal and state governments are considering additional privacy laws and regulations which, if passed, could further impact our business, strategies, offerings, and initiatives and cause us to incur further costs. Any actual or perceived failure to comply with the CCPA, other data privacy laws or regulations, or related contractual or other obligations, or any perceived privacy rights violation, could lead to investigations, claims, and proceedings by governmental entities and private parties,

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damages for contract breaches, and other significant costs, penalties, and other liabilities, as well as harm to our reputation and market position.

AI-related laws and regulations continue to remain uncertain and may vary from jurisdiction to jurisdiction. Our obligations to comply with the evolving legal and regulatory landscape may require us to incur significant additional costs or limit our ability to incorporate certain AI capabilities into our business operations or product offerings. As we integrate AI technologies into our business, we must navigate varying regulations that could impact our operations and product development. Additionally, the use of AI may also raise certain ethical issues or concerns, and while we are focused on developing and implementing AI responsibly, we may be unable to identify or resolve those issues before they arise. Failure to comply with these regulations or prevent AI-related issues or unintended consequences from occurring, could result in fines, penalties, or restrictions on our use of AI, which could adversely affect our business.

Outside of the United States, as a result of our business acquisitions, we are subject to an expanding set of privacy, data protection, and related regulatory requirements in jurisdictions where we conduct operations or process personal data. These laws may apply based on factors such as our establishment or operations in a jurisdiction or data processing activities conducted there. Certain international data protection regimes, including those in the European Union and the United Kingdom, impose specific obligations on the collection, use, sharing, and transfer of personal data. Compliance with these obligations may increase operational complexity and costs, limit our ability to use or transfer data across jurisdictions, or require changes to our products, services, or business practices. Enforcement approaches and penalties vary by jurisdiction and may include significant fines or other sanctions, as well as reputational harm.

Unfavorable outcomes of legal proceedings may adversely affect our business, reputation, financial condition, cash flows, and operating results.

We and our affiliates are involved in various disputes, governmental and/or regulatory inspections, investigations and proceedings, mass arbitrations, and litigation matters. For more information, see “– Contingencies and Litigation – Litigation and Regulatory Matters” in Note 18 – Commitments and Contingencies of the Notes to the Consolidated Financial Statements.

In addition, we, along with equipment manufacturers and other carriers, are subject to current and potential future lawsuits alleging adverse health effects arising from the use of wireless handsets or from wireless transmission equipment such as cell towers. In addition, the FCC has from time to time gathered data regarding wireless device emissions, and its assessment of the risks associated with using wireless devices may evolve based on its findings. The Department of Health and Human Services has indicated that it is undertaking a study on electromagnetic radiation and health research. Any allegations of adverse health effects or changes in risk assessments could result in customers purchasing fewer devices and wireless services, could result in significant legal and regulatory liability, and could have a material adverse effect on our business, reputation, financial condition, cash flows, and operating results.

Such legal proceedings can be complex, costly, and highly disruptive to our business operations by diverting the attention and energy of management and other key personnel. The assessment of the outcome of legal proceedings, including our potential liability, if any, is a highly subjective process that requires judgments about future events that are not within our control. The amounts ultimately received or paid upon settlement or pursuant to a final judgment, order, or decree may differ materially from amounts accrued in our financial statements. In addition, litigation or similar proceedings could impose restraints on our current or future manner of doing business. Such potential outcomes including judgments, awards, settlements or orders could have a material adverse effect on our business, reputation, financial condition, cash flows and operating results.

Our business may be adversely impacted if we are not able to protect our intellectual property rights or if we infringe on the intellectual property rights of others.

We rely on a variety of intellectual property assets, including patents, copyrights, trademarks, and domains, to maintain our competitiveness. If we are unable to protect our intellectual property due to factors such as changes in U.S. intellectual property laws, the value of our intellectual property may become impaired, which may adversely impact our business and financial results.

Additionally, we have faced and will continue to face various litigations alleging that our products or services infringe patents or other intellectual property of third parties, including potential litigation arising from our use of AI. If successful, these litigations could result in an award of financial compensation, including damages or royalties, business disruptions, reputational harm, or an order requiring that we cease offering, selling, and using the relevant products, equipment, services, and network functions. Defending against such litigation is not only costly and time-consuming, but it may also be disruptive to our business operations and divert resources and attention. Furthermore, the outcomes of these litigations are inherently uncertain.

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Our suppliers and vendors also face and will continue to face, intellectual property litigation related to the technology used in the products, equipment, and services they provide to us. If successful, such litigation against our suppliers and vendors might impact their ability to continue to provide the relevant products, equipment, and services to us.

We offer regulated financial services products. These products expose us to a wide variety of state and federal regulations.

The financing of devices, such as through our EIP, and the offering of co-branded banking products, such as our T-Mobile Money debit card and T-Mobile Visa credit card, impact our regulatory compliance obligations. Failure to remain compliant with applicable regulations may increase our risk exposure in the following areas:

•consumer complaints and potential examinations or enforcement actions by federal and state regulatory agencies, including, but not limited to, the Consumer Financial Protection Bureau, state attorneys general, the FCC, and the FTC; and

•regulatory fines, penalties, enforcement actions, civil litigation, and/or class action lawsuits. Failure to comply with applicable regulations and the realization of any of these risks could have a material adverse effect on our business, financial condition, and operating results.

Our business may be impacted by new or amended tax laws or regulations or administrative interpretations and judicial decisions affecting the scope or application of tax laws or regulations.

We are subject to a wide variety of federal, state, and local taxes, fees, and regulatory charges. Tax laws and regulations are dynamic and subject to change through new legislation and evolving legislative, regulatory, administrative, and judicial interpretations. Changes in tax laws or their interpretation or enforcement could affect our tax rates, tax liabilities, and the carrying value of deferred tax assets or liabilities.

With respect to taxes on our products and services, we calculate, collect, and remit various federal, state, and local taxes, fees, and regulatory charges (“taxes”) to numerous governmental authorities, including sales taxes, Universal Service Fund contributions, common carrier regulatory charges, and public safety fees. Because many of our service plans are tax inclusive, increases in such taxes may adversely impact our business results.

In many cases, the application of existing, newly enacted, or amended tax laws may be uncertain and subject to different interpretations, especially when evaluated against new technologies and telecommunications services, such as broadband internet access and cloud-related services. Legislative changes, administrative interpretations, and judicial decisions affecting the scope or application of tax laws could also impact reported revenue and taxes due on tax inclusive plans. Additionally, failure to comply with any applicable tax laws could subject us to additional taxes, fines, penalties, or other adverse actions.

Our wireless licenses are subject to renewal and may be revoked in the event that we violate applicable laws.

Our existing wireless licenses are subject to renewal upon the expiration of the period for which they are granted. Our licenses have been granted with an expectation of renewal, and the FCC generally has approved our license renewal applications. However, the Communications Act provides that licenses may be revoked for cause and license renewal applications denied if the FCC determines that a renewal would not serve the public interest. If we fail to timely file to renew any wireless license or fail to meet any regulatory requirements for renewal, including construction and substantial service requirements, we could be denied a license renewal. Many of our wireless licenses are subject to interim or final construction requirements, and there is no guarantee that the FCC will find our construction, or the construction of prior licensees, sufficient to meet the build-out or renewal requirements. Accordingly, we cannot assure that the FCC will renew our wireless licenses upon their expiration. If any of our wireless licenses were to be revoked or not renewed upon expiration, we would not be permitted to provide services under that license, which could have a material adverse effect on our business, financial condition, and operating results.

Risks Related to Ownership of Our Common Stock

Our Certificate of Incorporation designates the Court of Chancery of the State of Delaware as the sole and exclusive forum for certain actions and proceedings, which could limit the ability of our stockholders to obtain a judicial forum of their choice for disputes with the Company or its directors, officers, or employees.

Our Certificate of Incorporation provides that, unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware shall be the sole and exclusive forum for (i) any derivative action or proceeding brought on

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behalf of the Company, (ii) any action asserting a claim of breach of a fiduciary duty owed by any director, officer or employee of the Company to the Company or its stockholders, (iii) any action asserting a claim arising pursuant to any provision of the General Corporation Law of the State of Delaware, the Certificate of Incorporation or the Company's bylaws, or (iv) any other action asserting a claim arising under, in connection with, and governed by the internal affairs doctrine. This choice of forum provision does not waive our compliance with our obligations under the federal securities laws and the rules and regulations thereunder. Moreover, the provision does not apply to suits brought to enforce a duty or liability created by the Exchange Act or by the Securities Act of 1933, as amended.

This choice of forum provision may increase costs to bring a claim, discourage claims, or limit a stockholder's ability to bring a claim in a judicial forum that the stockholder finds favorable for disputes with the Company or its directors, officers or employees, which may discourage such lawsuits against the Company and its directors, officers and employees, even though an action, if successful, might benefit our stockholders. Alternatively, if a court were to find the choice of forum provision to be inapplicable or unenforceable in an action, we may incur additional costs associated with resolving such matters in other jurisdictions, which could increase our costs of litigation and adversely affect our business and financial condition.

DT controls a majority of the voting power of our common stock and the T-Mobile trademarks we utilize in our business and may have interests that differ from the interests of our other stockholders.

DT controls a majority of the voting power of our common stock and therefore we are a “controlled company,” as defined in the NASDAQ Stock Market LLC (“NASDAQ”) listing rules, and we are not subject to NASDAQ requirements that would otherwise require us to have a majority of independent directors, a nominating committee composed solely of independent directors or a compensation committee composed solely of independent directors. Accordingly, our stockholders will not be afforded the same protections as stockholders of other NASDAQ-listed companies generally receive with respect to corporate governance for so long as we rely on these exemptions from the corporate governance requirements.

In addition, pursuant to our Certificate of Incorporation and the Second Amended and Restated Stockholders’ Agreement, as long as DT beneficially owns 30% or more of our outstanding common stock, we are restricted from taking certain actions without DT’s prior written consent, including (i) incurring indebtedness above certain levels based on a specified debt to cash flow ratio, (ii) taking any action that would cause a default under any instrument evidencing indebtedness involving DT or its affiliates, (iii) acquiring or disposing of assets or entering into mergers or similar acquisitions in excess of $1.0 billion, (iv) changing the size of our Board of Directors, (v) subject to certain exceptions, issuing equity of 10% or more of the then-outstanding shares of our common stock, or issuing equity to redeem debt held by DT, (vi) repurchasing or redeeming equity securities or making any extraordinary or in-kind dividend other than on a pro rata basis, or (vii) making certain changes involving our CEO. We are also restricted from amending our Certificate of Incorporation and bylaws in any manner that could adversely affect DT’s rights under the Second Amended and Restated Stockholders’ Agreement for as long as DT beneficially owns 5% or more of our outstanding common stock. These restrictions could prevent us from taking actions that our Board of Directors might otherwise determine are in the best interests of the Company and our stockholders, or that may be in the best interests of our other stockholders.

DT effectively has control over all matters submitted to our stockholders for approval, including the election or removal of directors, changes to our Certificate of Incorporation, a sale or merger of our Company and other transactions requiring stockholder approval under Delaware law. DT’s controlling interest may have the effect of making it more difficult for a third party to acquire, or discouraging a third party from seeking to acquire, the Company and DT, as the controlling stockholder, may have strategic, financial, or other interests different from those of our other stockholders, including as the holder of a portion of our debt and as the counterparty in a number of commercial arrangements, and may make decisions adverse to the interests of our other stockholders.

In addition, we license certain trademarks from DT, including the right to use the trademark “T-Mobile” as a name for the Company and our flagship brand under a trademark license agreement, as amended, with DT. As described in more detail in our Proxy Statement on Schedule 14A filed with the SEC on April 18, 2025 under the heading “Transactions with Related Persons and Approval,” we are obligated to pay DT a royalty in an amount equal to 0.25% (the “royalty rate”) of the net revenue (as defined in the trademark license) generated by products and services sold by the Company under the licensed trademarks subject to a cap of $80 million per calendar year through December 31, 2028. We and DT are obligated to negotiate a new trademark license when (i) DT has 50% or less of the voting power of the outstanding shares of capital stock of the Company or (ii) any third party owns or controls, directly or indirectly, 50% or more of the voting power of the outstanding shares of capital stock of the Company, or otherwise has the power to direct or cause the direction of the management and policies of the Company. If we and DT fail to agree on a new trademark license, either we or DT may terminate the trademark license and such termination shall be effective, in the case of clause (i) above, on the third anniversary after a notice of termination and, in the case of clause (ii) above, on the second anniversary after a notice of termination. A further increase in the royalty rate or

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termination of the trademark license could have a material adverse effect on our business, financial condition, and operating results.

We cannot guarantee that our current and future stockholder return programs will be fully utilized or that they will enhance long-term stockholder value.

Our Board of Directors has authorized, and may from time to time authorize, stockholder return programs, consisting of repurchases of shares of our common stock, the payment of cash dividends, or both. The specific timing and amount of any share repurchases and any dividend payments under any stockholder return program will depend on prevailing share prices, general economic and market conditions, Company performance and other considerations, such as whether the Company determines that there are other uses for the funds currently authorized for the program that would be more advantageous for our business. In addition, the specific timing and amount of any dividend payments are subject to declaration on future dates by the Board of Directors in its sole discretion.

Any stockholder return program could impact our cash flows, affect the trading price of our common stock, and increase volatility. We cannot guarantee that any stockholder return program will be fully consummated or that it will enhance long-term stockholder value. Our current and future stockholder return programs do not, and will not, obligate the Company to acquire any particular amount of common stock or to declare and pay any particular amount of dividends, and any program may be suspended or discontinued at any time at the Company’s discretion. Any announcement of termination of any program may result in a decrease in the price of our common stock.

Future sales of our common stock by DT and foreign ownership limitations by the FCC could have a negative impact on our stock price and decrease the value of our stock.

We cannot predict the effect, if any, that market sales of shares of our common stock by DT will have on the prevailing trading price of our common stock. Sales of a substantial number of shares of our common stock could cause our stock price to decline.

We and DT are parties to the Second Amended and Restated Stockholders’ Agreement pursuant to which DT is free to transfer its shares in public sales without notice, as long as such transactions would not result in a third party owning more than 30% of the outstanding shares of our common stock. If a transfer were to exceed the 30% threshold, it would be prohibited unless the transfer were approved by our Board of Directors, or the transferee were to make a binding offer to purchase all of the other outstanding shares on the same price and terms. The Second Amended and Restated Stockholders’ Agreement does not otherwise impose any other restrictions on the sales of common stock by DT. Moreover, the Second Amended and Restated Stockholders’ Agreement generally requires us to cooperate with DT to facilitate the resale of our common stock or debt securities held by DT under shelf registration statements we have filed.

DT has incrementally sold limited amounts of shares of our common stock in the open market. Any additional sale of shares of our common stock by DT (other than in transactions involving the purchase of all of our outstanding shares) could significantly increase the number of shares available in the market, which could cause a decrease in our stock price. In addition, even if DT does not sell a large number of its shares into the market, their rights to transfer a large number of shares into the market could depress our stock price.

Furthermore, under existing law, no more than 20% of an FCC licensee’s capital stock may be directly owned, or no more than 25% indirectly owned, or voted by non-U.S. citizens or their representatives, by a foreign government or its representatives or by a foreign corporation. If an FCC licensee is controlled by another entity, up to 25% of that entity’s capital stock may be owned or voted by non-U.S. citizens or their representatives, by a foreign government or its representatives or by a foreign corporation. Foreign ownership above the 25% holding company level may be allowed if the FCC finds such higher levels consistent with the public interest. The FCC has ruled that higher levels of foreign ownership, even up to 100%, are presumptively consistent with the public interest with respect to investors from certain nations. If our foreign ownership by previously unapproved foreign parties were to exceed the permitted level without further FCC authorization, the FCC could subject us to a range of penalties, including an order for us to divest the foreign ownership in part, fines, license revocation or denials of license renewals. If ownership of our common stock by an unapproved foreign entity were to become subject to such limitations, or if any ownership of our common stock violates any other rule or regulation of the FCC applicable to us, our Certificate of Incorporation provides for certain redemption provisions at a pre-determined price which may be less than fair market value. These limitations and our Certificate of Incorporation may limit our ability to attract additional equity financing outside the United States and decrease the value of our common stock.

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Item 1B. Unresolved Staff Comments

None.

Item 1C. Cybersecurity

Risk Management and Strategy

Our Cybersecurity Approach and Integration

We have implemented processes for overseeing and identifying material risks from cybersecurity threats, and our cybersecurity processes are integrated into the Company’s overall risk management system and processes. As part of management’s oversight of cybersecurity, Mark Clancy, our Senior Vice President, Cybersecurity, presents on our cybersecurity practices to the Nominating, Corporate Governance and Compliance Committee of our Board of Directors (the “NCGC Committee”) and to our full Board of Directors on a periodic basis. Our Chief Audit Executive periodically presents enterprise risks, including cybersecurity risks, to the Audit Committee of our Board of Directors (the “Audit Committee”). Our Chief Compliance Officer regularly attends meetings of the NCGC Committee to provide insights from the compliance perspective relating to cybersecurity.

Cyber risk management is a core component of the Company's governance structure. We utilize the National Institute of Standards and Technology’s Cybersecurity Framework as a guide in cyber risk management to identify, assess, and assist cybersecurity leadership in managing cybersecurity risks. Cyber risk management encompasses partnerships among teams that are responsible for cyber governance, prevention, detection, and remediation activities within the Company’s cybersecurity environment. As part of our cyber risk management efforts, we conduct periodic reviews and collaborate with enterprise-wide risk assessments to assess and manage cybersecurity risks. Our cybersecurity team also provides enterprise-wide cybersecurity training for employees to continuously improve our mitigation against human-driven vulnerabilities.

Our management also conducts a quarterly enterprise-wide risk assessment that considers a wide spectrum of risks facing the Company, including cybersecurity. Through these quarterly risk assessments, management informs the Audit Committee of the cyber risk landscape facing the Company and the Company’s preparedness to manage such risk. The enterprise-wide risk assessment is a top-down risk assessment that leverages the assessments performed by cyber risk management.

Engagement with External Experts

The Company engages top-tier external cybersecurity firms, as needed, leveraging their expertise as part of our ongoing effort to evaluate and enhance our cybersecurity program. They help with cyber defense capabilities (including staff enhancement of certain functions) and transformation to mitigate associated threats, reduce risk, enhance our cybersecurity posture, and meet the Company's evolving needs.

Oversight of Third-Party Service Providers

Our third-party risk management program includes processes for identifying and managing material cybersecurity risks arising from third-party providers. Our third-party risk management program actively engages with the enterprise-wide risk assessment process and partners with cyber risk management to report relevant risks to the NCGC Committee, the Audit Committee and our internal Enterprise Risk & Compliance Committee. Our third-party risk management program includes cybersecurity as an aspect of its risk assessment of third parties with the objective that key risks are identified and addressed. Moreover, the program also considers risks associated with certain fourth parties, entities that are partners or subcontractors of our direct third-party vendors, through assessments carried out by our third-party service providers.

Cybersecurity Incident Impact

As previously disclosed, in August 2021, we experienced a cybersecurity incident that resulted in numerous lawsuits, including mass arbitration claims and multiple class action lawsuits. In January 2023, we experienced another cybersecurity incident that also resulted in consumer class actions and regulatory inquiries. Legal and other costs related to these proceedings and inquiries, as well as any potential future actions, may be substantial, and losses associated with any adverse judgments, settlements, penalties or other resolutions of such proceedings and inquiries could be material to our business, reputation, financial condition, cash flows and operating results. For additional details regarding the impact of both cybersecurity incidents, see Note 18 – Commitments and Contingencies of the Notes to the Consolidated Financial Statements.

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We have not identified other known risks from previous cybersecurity threats that have materially affected or are reasonably likely to materially affect us. However, we face ongoing risks from certain cybersecurity threats that, if realized, are reasonably likely to materially affect business strategy, financial condition or operating results. See “Risk Factors – We have experienced cyberattacks and could in the future be further harmed by disruption, data loss or other security breaches, whether directly or indirectly through third parties whose products and services we rely on in operating our business.”

Governance

Disclosure of Management’s Responsibilities

Chief Information Officer

The Chief Information Officer is responsible for overseeing the Company’s information technology systems, digital capabilities, and cybersecurity practices. Mark Clancy, our Senior Vice President, Cybersecurity, under the direction of the Chief Information Officer, is responsible for overseeing the cybersecurity organization and promoting a security-centric culture throughout our business and operational functions. The Senior Vice President, Cybersecurity, is at the forefront of enhancing our cybersecurity framework and strengthening the overall cybersecurity program. This involves upgrading tools and capabilities, which are part of a broader, multi-year strategy to continue to enhance security measures. The Senior Vice President, Cybersecurity, oversees the cyber risk management function, which identifies cybersecurity threats, assesses cybersecurity risks and supports the Chief Information Officer and the Company in managing such risks.

As the Company’s Chief Information Officer, Jeff Simon has extensive experience in risk management and information security, including serving as the Chief Information Security Officer at Fidelity National Information Services, Inc. Mr. Simon received his Master of Science in Computer Science, Software Engineering & Artificial Intelligence from the Johns Hopkins Whiting School of Engineering and Bachelor of Science in Business Administration and Applied Economics from Marquette University. Mr. Simon is a Certified Information Systems Security Professional.

As the Company’s Senior Vice President, Cybersecurity, Mark Clancy has over 25 years of experience in information technology, information security, and cybersecurity, including serving as the Chief Information and Security Officer and Vice President of Cybersecurity and Fraud at Sprint Corporation. Mr. Clancy received his Bachelor of Science in Electrical and Electronics Engineering from Drexel University.

Enterprise Risk & Compliance Committee

Our Enterprise Risk & Compliance Committee is comprised of a collective of senior management representatives and subject matter experts from across the Company. The Enterprise Risk & Compliance Committee is chaired by the Chief Financial Officer of the Company, with the Chief Legal Officer and General Counsel as the co-chair and comprises core members including the Chief Information Officer, while the Senior Vice President, Cybersecurity, serves in an advisory capacity. The purpose of the Enterprise Risk & Compliance Committee is to oversee and govern the Company’s risk management, environmental, social, corporate governance, cybersecurity, and operational compliance activities, as well as provide a means of bringing risk issues to the attention of management. Specific to cybersecurity, the Chief Information Officer and the Senior Vice President, Cybersecurity, have the expertise to provide insights into the nature of cyber threats, the Company’s readiness, and actions taken to mitigate such risks.

Disclosure of the Board’s Roles and Responsibilities

Our Board of Directors oversees risks from cybersecurity threats using a multi-faceted approach that involves the NCGC Committee and Audit Committee and various executive roles. Additionally, our Chief Information Officer and Senior Vice President, Cybersecurity, report on cybersecurity to the full Board.

Nominating, Corporate Governance and Compliance Committee

The NCGC Committee oversees risks associated with data privacy and information security, which encompasses cybersecurity. Our Senior Vice President, Cybersecurity, and Chief Compliance Officer, among other executives, provide periodic reports to the NCGC Committee and also meet with the NCGC Committee to discuss any material events when they arise. The periodic reports are designed to keep the NCGC Committee abreast of the Company’s cybersecurity practices, risks and trends in cybersecurity threats. The NCGC Committee also has discussions with management focused on evaluating the Company’s exposure to cybersecurity risks and cybersecurity practices in place to mitigate such risks. These discussions enable the NCGC Committee to be informed of the steps management is taking to detect, monitor and manage cybersecurity risks. These reports

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to the NCGC Committee typically include information on any significant incidents that have occurred, how they were managed, and any changes to the risk profile of the Company. The NCGC Committee seeks updates to facilitate proactive governance and to allow the NCGC Committee to address emerging cybersecurity issues with management.

Audit Committee

The Audit Committee is integral to overseeing the Company’s overall risk management strategies, including cybersecurity risks and disclosures. To keep the Audit Committee informed, the Chief Audit Executive maintains a direct and open communication channel with the Audit Committee. Regular meetings are held for the Chief Audit Executive to report to the Audit Committee. These include an enterprise-wide risk assessment that highlights cybersecurity risks and cybersecurity risk mitigation actions. Additionally, the Audit Committee receives updates on significant incidents and cybersecurity risks that have been presented to or discussed with the Enterprise Risk & Compliance Committee.

Item 2. Properties

Our properties are best described on a collective basis, as no individual property is material. Our property and equipment consists of the following:


(percent of gross property and equipment)	December 31, 2025		December 31, 2024
Wireless communications systems	71	%	71	%
Land, buildings and building equipment	5	%	5	%
Data processing equipment and other	24	%	24	%
Total	100	%	100	%

Wireless communications systems primarily consist of assets used to operate our wireless network and information technology data centers, including switching equipment, radio frequency equipment, tower assets, 5G broadband gateways, construction in progress and leasehold improvements related to the wireless network and asset retirement costs.

Land, buildings and building equipment primarily consist of land and land improvements, central office buildings or any other buildings that house network equipment, buildings used for administrative and other purposes, related construction in progress and certain network service equipment.

Data processing equipment and other primarily consist of data processing equipment, office equipment, capitalized software, leased wireless devices, construction in progress and leasehold improvements.

We also lease distributed antenna systems and small cell sites, as well as properties throughout the United States that contain data and switching centers, customer call centers, retail locations, warehouses and administrative spaces.

Item 3. Legal Proceedings

For more information regarding the legal proceedings in which we are involved, see Note 1 8 – Commitments and Contingencies of the Notes to the Consolidated Financial Statements.

Item 4. Mine Safety Disclosures

Not applicable.

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PART II.

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

Market Information

Our common stock is traded on the NASDAQ Global Select Market under the symbol “TMUS.” We are included within the S&P 500 in the Wireless Telecommunication Services GICS (Global Industry Classification Standard) Sub-Industry index. As of February 6, 2026, there were 13,410 registered stockholders of record of our common stock, but we estimate the total number of stockholders to be much higher as a number of our shares are held by brokers or dealers for their customers in street name.

During the year ended December 31, 2025, we declared and paid cash dividends totaling $3.66 per share, as part of our 2025 Stockholder Return Program (as defined below). Additionally, on December 4, 2025, our Board of Directors declared a quarterly cash dividend of $1.02 per share on our issued and outstanding common stock, which will be paid on March 12, 2026, to stockholders of record as of the close of business on February 27, 2026, as part of our 2026 Stockholder Return Program (as defined below).

Issuer Purchases of Equity Securities

The table below provides information regarding our share repurchases during the three months ended December 31, 2025:


(in millions, except share and per share amounts)	Total Number of Shares Purchased	Average Price Paid per Share		Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs	Approximate Dollar Value of Shares that may yet be Purchased Under the Plans or Programs (1)
October 1, 2025 - October 31, 2025	1,246,978	$	215.24	1,246,978	$	3,340
November 1, 2025 - November 30, 2025	5,218,414	209.36		5,218,414	2,248
December 1, 2025 - December 31, 2025	5,453,744	201.51		5,453,744	14,614
Total	11,919,136			11,919,136

(1) On December 13, 2024, we announced that our Board of Directors authorized a stockholder return program for up to an additional $14.0 billion through December 31, 2025 (the “2025 Stockholder Return Program”). On December 11, 2025, we announced that our Board of Directors authorized a stockholder return program for up to an additional $14.6 billion that will run through December 31, 2026 (the “2026 Stockholder Return Program”). The amounts presented represent the remaining dollar amount authorized for purchase under the 2025 Stockholder Return Program and 2026 Stockholder Return Program, as applicable, as of the end of the period, which has been reduced by the amount of any cash dividends declared and paid by the Company.

See Note 15 - Stockholder Return Programs of the Notes to the Consolidated Financial Statements for more information about our 2025 Stockholder Return Program and 2026 Stockholder Return Program.

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Performance Graph

The graph below compares the five-year cumulative total returns of T-Mobile, the S&P 500 index, the NASDAQ Composite index and the Dow Jones US Mobile Telecommunications TSM index. The graph tracks the performance of a $100 investment, with the reinvestment of all dividends, from December 31, 2020 to December 31, 2025.

The five-year cumulative total returns of T-Mobile, the S&P 500 index, the NASDAQ Composite index and the Dow Jones US Mobile Telecommunications TSM index, as illustrated in the graph above, are as follows:


	At December 31,
(in dollars)	2020		2021		2022		2023		2024		2025
T-Mobile US, Inc.	$	100.00	$	86.01	$	103.82	$	119.41	$	166.80	$	155.79
S&P 500	100.00		128.71		105.40		133.10		166.40		196.16
NASDAQ Composite	100.00		122.18		82.43		119.22		154.48		187.14
Dow Jones US Mobile Telecommunications TSM	100.00		91.37		82.48		88.64		108.82		112.06

The stock price performance included in this graph is not necessarily indicative of future stock price performance.

Item 6. [Reserved]

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Overview

The objectives of our Management’s Discussion and Analysis of Financial Condition and Results of Operations (“MD&A”) are to provide users of our consolidated financial statements with the following:

•A narrative explanation from the perspective of management of our financial condition, results of operations, cash flows, liquidity and certain other factors that may affect future results;

•Context to the consolidated financial statements; and

•Information that allows assessment of the likelihood that past performance is indicative of future performance.

Our MD&A is provided as a supplement to, and should be read together with, our audited consolidated financial statements as of December 31, 2025 and 2024, and for each of the three years in the period ended December 31, 2025, included in Part II, Item 8 of this Form 10-K. Except as expressly stated, the financial condition and results of operations discussed throughout our MD&A are those of T-Mobile US, Inc. and its consolidated subsidiaries.

Acquisition of UScellular Wireless Business

Transaction Overview

On May 24, 2024, we entered into a securities purchase agreement with United States Cellular Corporation (“UScellular”), Telephone and Data Systems, Inc., and USCC Wireless Holdings, LLC for the acquisition of substantially all of UScellular’s wireless operations and select AWS, PCS, 600 MHz, 700 MHz and other spectrum assets for an aggregate purchase price of approximately $4.4 billion, payable in cash and the assumption of up to $2.0 billion of debt through exchange offers to certain UScellular debtholders.

On May 23, 2025, we launched exchange offers (the “Exchange Offers”) for any and all of certain outstanding senior notes of UScellular for new notes of T-Mobile with the same interest rate, interest payment dates, maturity dates and redemption terms as each corresponding series of senior notes of UScellular. In conjunction with the Exchange Offers, we also solicited consents for each series of the outstanding senior notes of UScellular to effect a number of amendments to the applicable indenture under which each such series of notes were issued and are governed (the “Consent Solicitations”). The consummation of the Exchange Offers and Consent Solicitations were subject to the closing of the UScellular Acquisition (as defined below), which occurred on August 1, 2025.

On July 22, 2025, we entered into asset purchase agreements for the acquisition of substantially all of the wireless operations assets (together with UScellular’s wireless operations and select spectrum assets, the “UScellular Wireless Business”) of each of Farmers Cellular Telephone Company, Inc., Iowa RSA No. 9 Limited Partnership, and Iowa RSA No. 12 Limited Partnership (collectively, the “Iowa Entities”) for an aggregate purchase price of $175 million payable in cash. Prior to our acquisition of the Iowa Entities, UScellular held a minority interest in each of the Iowa Entities.

The UScellular Wireless Business offers a comprehensive range of wireless communications products and services. As a combined company, we expect to increase competition in the telecommunications industry, achieve synergies and enhance our rural 5G coverage with our combined network footprint. Following the closing of the transactions, UScellular and the Iowa Entities will retain ownership of their other spectrum licenses, as well as their towers.

On August 1, 2025, upon the completion of certain customary closing conditions, including the receipt of certain regulatory approvals (the “UScellular Acquisition Date”), we completed the acquisition of the UScellular Wireless Business, and as a result, the UScellular Wireless Business became wholly owned by T-Mobile. In exchange, on the UScellular Acquisition Date, we transferred cash of $2.8 billion. Additionally, the closing of the UScellular Acquisition obligated us to execute the Exchange Offers. On August 5, 2025, we executed the Exchange Offers of certain senior notes of UScellular with an aggregate outstanding principal balance of $1.7 billion for T-Mobile notes with the same interest rate, interest payment dates, maturity dates and redemption terms as each corresponding series of senior notes of UScellular.

For more information regarding the UScellular Acquisition, see Note 2 – Business Combinations of the Notes to the Consolidated Financial Statements.

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UScellular Merger-Related Costs

Merger-related costs associated with the UScellular Acquisition to date include:

•Integration costs to achieve efficiencies in network, retail, information technology and back office operations and migrate customers to the T-Mobile network and billing systems;

•Restructuring costs, including contract terminations, severance and network decommissioning; and

•Transaction costs, including legal and professional services related to the completion of the UScellular Acquisition.

UScellular merger-related costs have been excluded from our calculations of Adjusted EBITDA and Core Adjusted EBITDA, which are non-GAAP financial measures, as we do not consider these costs to be reflective of our ongoing operating performance. See “Adjusted EBITDA and Core Adjusted EBITDA” in the “Performance Measures” section of this MD&A. Net cash payments for UScellular merger-related costs, including payments related to our restructuring plan, are included in Net cash provided by operating activities on our Consolidated Statements of Cash Flows and our calculation of Adjusted Free Cash Flow.

UScellular merger-related costs are presented below:


(in millions)	Year Ended December 31,			Change
		2025		2024		$		%
UScellular merger-related costs
Cost of services, exclusive of depreciation and amortization		$	31	$	—	$	31	NM
Cost of equipment sales, exclusive of depreciation and amortization		10		—		10		NM
Selling, general and administrative		222		26		196		754	%
Total UScellular merger-related costs		$	263	$	26	$	237	912	%

Net cash payments for UScellular merger-related costs		$	139	$	22	$	117	532	%

NM - Not meaningful

Anticipated Impacts

As a result of our UScellular Acquisition restructuring and integration activities, we expect to realize cost efficiencies by eliminating redundancies within our combined network as well as other business processes and operations. Upon completion of these activities, we expect to achieve total annual run rate cost synergies of $1.2 billion, consisting of $950 million in operating expenses and $250 million in capital expenditures, with costs to achieve expected to be approximately $2.6 billion.

Our restructuring and integration activities associated with the UScellular Acquisition are expected to occur over the next two years with substantially all costs incurred and associated cash payments made by the end of fiscal year 2027. We are evaluating additional restructuring initiatives associated with the UScellular Acquisition, which are dependent on consultations and negotiations with certain counterparties and the expected impact on our business operations, which could affect the amount or timing of the costs and related payments.

Acquisition of Vistar Media Inc.

On December 20, 2024, we entered into an agreement and plan of merger for the acquisition of 100% of the outstanding capital stock of Vistar Media Inc. (“Vistar”), a provider of technology solutions for digital-out-of-home advertisements (the “Vistar Acquisition”).

Upon the completion of certain customary closing conditions, including the receipt of certain regulatory approvals, on February 3, 2025 (the “Vistar Acquisition Date”), we completed the Vistar Acquisition, and as a result, Vistar became a wholly owned subsidiary of T-Mobile. In exchange, we transferred cash of $621 million.

For more information regarding the Vistar Acquisition, see Note 2 – Business Combinations of the Notes to the Consolidated Financial Statements.

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Acquisition of Blis Holdco Limited

On February 18, 2025, we entered into a share purchase agreement for the acquisition of 100% of the outstanding capital stock of Blis Holdco Limited (“Blis”), a provider of advertising solutions (the “Blis Acquisition”).

Upon the completion of certain customary closing conditions, including the receipt of certain regulatory approvals, on March 3, 2025 (the “Blis Acquisition Date”), we completed the Blis Acquisition, and as a result, Blis became a wholly owned subsidiary of T-Mobile. In exchange, we transferred cash of $180 million.

For more information regarding the Blis Acquisition, see Note 2 – Business Combinations of the Notes to the Consolidated Financial Statements.

Acquisition of Ka’ena Corporation

On May 1, 2024 (the “Ka’ena Acquisition Date”), we completed the merger with Ka’ena Corporation and its subsidiaries, including, among others, Mint Mobile LLC (collectively, “Ka’ena”), and as a result, Ka’ena became a wholly owned subsidiary of T-Mobile (the “Ka’ena Acquisition”). The total purchase price consists of an upfront payment on the Ka’ena Acquisition Date and an earnout payable in the third quarter of 2026. On the Ka’ena Acquisition Date, and in satisfaction of the upfront payment, we transferred $420 million in cash and 3,264,952 shares of T-Mobile common stock valued at $536 million as determined based on its closing market price on April 30, 2024, for a total payment fair value of $956 million. A portion of the upfront payment made on the Ka’ena Acquisition Date was for the settlement of the preexisting wholesale relationship with Ka’ena. The amount of the upfront payment was subject to customary adjustments, and as a result of such adjustments, $17 million of the upfront payment was returned to T-Mobile during the fourth quarter of 2024, which resulted in a commensurate increase in the maximum payable in satisfaction of the earnout.

Based on the adjusted amount paid upfront, an additional $420 million in future cash and T-Mobile common stock is payable in satisfaction of the earnout.

Prior to the Ka’ena Acquisition, Ka’ena was a wholesale partner of the Company for which we recognized service revenues within Wholesale and other service revenues. Upon the closing of the Ka’ena Acquisition, this relationship was effectively terminated, and the Company acquired Ka’ena’s prepaid customer relationships and began to recognize service revenues associated with these customers within Prepaid revenues and operating expenses primarily within Selling, general and administrative expenses on our Consolidated Statements of Comprehensive Income subsequent to the Ka’ena Acquisition Date.

For more information regarding the Ka’ena Acquisition, see Note 2 – Business Combinations of the Notes to the Consolidated Financial Statements.

Sprint Merger-Related Costs

Sprint Merger-related costs generally include:

•Integration costs to achieve efficiencies in network, retail, information technology and back office operations, migrate customers to the T-Mobile network and billing systems and the impact of legal matters assumed as part of the Merger;

•Restructuring costs, including severance, store rationalization and network decommissioning; and

•Transaction costs, including legal and professional services related to the completion of the transactions.

Sprint Merger-related costs have been excluded from our calculations of Adjusted EBITDA and Core Adjusted EBITDA, which are non-GAAP financial measures, as we do not consider these costs to be reflective of our ongoing operating performance. See “Adjusted EBITDA and Core Adjusted EBITDA” in the “Performance Measures” section of this MD&A. Net cash payments for Sprint Merger-related costs, including payments related to our restructuring plan, are included in Net cash provided by operating activities on our Consolidated Statements of Cash Flows and our calculation of Adjusted Free Cash Flow.

During the year ended December 31, 2024, we recognized a gain for the $100 million extension fee previously paid by DISH associated with the DISH License Purchase Agreement (as defined in Note 7 – Goodwill, Spectrum License Transactions and Other Intangible Assets of the Notes to the Consolidated Financial Statements) as a reduction to Selling, general and administrative expenses on our Consolidated Statements of Comprehensive Income. The gain was presented as a reduction in Merger-related costs and excluded from our calculations of Adjusted EBITDA and Core Adjusted EBITDA. See Note 7 –

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Goodwill, Spectrum License Transactions and Other Intangible Assets of the Notes to the Consolidated Financial Statements for more information.

As of June 30, 2024, we have incurred substantially all restructuring and integration costs associated with the Sprint Merger and, accordingly, no longer separately disclose Sprint Merger-related costs. The cash payments for the Sprint Merger-related costs incurred extend beyond 2025 and primarily relate to operating leases for which we have recognized accelerated lease expense.

Sprint Merger-related costs are presented below:


(in millions)	Year Ended December 31,			2025 Versus 2024				2024 Versus 2023
		2025		2024		2023		$ Change		% Change		$ Change		% Change
Sprint Merger-related costs
Cost of services, exclusive of depreciation and amortization		$	—	$	180	$	652	$	(180)	(100)	%	$	(472)	(72)	%
Cost of equipment sales, exclusive of depreciation and amortization		—		—		(12)		0		NM		12		(100)	%
Selling, general and administrative		—		(59)		394		59		(100)	%	(453)		(115)	%
Total Sprint Merger-related costs		$	—	$	121	$	1,034	$	(121)	(100)	%	$	(913)	(88)	%

Net cash payments for Sprint Merger-related costs		$	219	$	767	$	1,973	$	(548)	(71)	%	$	(1,206)	(61)	%

NM - Not meaningful

Joint Ventures

On April 24, 2024, we entered into a definitive agreement with a fund operated by EQT, EQT Infrastructure VI (“Fund VI”), to establish a joint venture between us and Fund VI to acquire Lumos (“Lumos”), a fiber-to-the-home platform, from EQT’s predecessor fund, EQT Infrastructure III. On April 1, 2025, we completed the joint acquisition of Lumos, upon the completion of certain customary closing conditions, including the receipt of certain regulatory approvals. During the three months ended June 30, 2025, we invested $932 million to acquire a 50% equity interest in the joint venture and 97,000 fiber customers. The funds invested by us will be used by the joint venture to fund future fiber builds. In addition, pursuant to the definitive agreement, we expect to make an additional capital contribution of approximately $500 million between 2027 and 2028 under the existing business plan. Following the joint acquisition, Lumos transitioned to a wholesale model where we are the anchor tenant owning residential and small business customer relationships.

On July 18, 2024, we entered into a definitive agreement with KKR & Co. Inc. to establish a joint venture to acquire Metronet Holdings, LLC and certain of its affiliates (collectively, “Metronet”), a fiber-to-the-home platform. On July 24, 2025, we completed the joint acquisition of Metronet upon the completion of certain customary closing conditions, including the receipt of certain regulatory approvals. During the three months ended September 30, 2025, we invested $4.6 billion to acquire a 50% equity interest in the joint venture and 713,000 residential fiber customers. Following the joint acquisition, Metronet became a wholesale services provider, and its residential fiber retail operations and customers transitioned to us. We do not anticipate making further capital contributions under the existing business plan.

We account for the Lumos and Metronet joint ventures under the equity method of accounting with our proportionate share of earnings (losses) presented within Other (expense) income, net on our Consolidated Statements of Comprehensive Income. We recognize revenues for fiber customers and the related wholesale costs paid to the joint ventures for network access within Postpaid revenues and Cost of services, respectively, on our Consolidated Statements of Comprehensive Income.

The joint ventures will focus on market identification and selection, build plans, network engineering and design, network deployment and customer installation, with us owning customer relationships and selling fiber service under the T-Mobile brand.

For more information regarding the Lumos and Metronet joint ventures, see Note 3 – Joint Ventures of the Notes to the Consolidated Financial Statements.

Network Restructuring Initiative

Recent technological advancements have enhanced our Customer-Driven Coverage insights, enabling us to identify, assess and shut down low customer value sites. In the fourth quarter of 2025, we began implementing restructuring initiatives to identify

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and realize these cost savings on our network, excluding activities associated with the UScellular Acquisition (the “Network Restructuring Initiative”). The major activities associated with the Network Restructuring Initiative include the rationalization of network and backhaul services and the decommissioning of cell sites and distributed antenna systems to reduce our overall network cost. Our Network Restructuring Initiative also includes the termination of certain of our operating leases for cell sites and switch sites.

Network Restructuring Initiative costs are presented below:


	Year Ended December 31, 2025
(in millions)
Network Restructuring Initiative
Cost of services, exclusive of depreciation and amortization	$	93
Depreciation and amortization	97
Total Network Restructuring Initiative costs	$	190

Our Network Restructuring Initiative is expected to occur over the next two years with a majority of costs incurred by the end of fiscal year 2026. We currently expect to incur between $500 million and $800 million of costs associated with the Network Restructuring Initiative.

We are evaluating additional restructuring activities associated with the Network Restructuring Initiative, which are dependent on consultations and negotiations with certain counterparties and the expected impact on our business operations, which could affect the amount or timing of the restructuring costs and related payments.

See Note 19 – Restructuring Costs of the Notes to the Consolidated Financial Statements for more information.

2025 Workforce Transformation

In the fourth quarter of 2025, we began implementing a restructuring initiative to streamline operations by centralizing leaders and teams, reducing organizational layers, and eliminating duplicative roles (the “2025 Workforce Transformation”). We intend to reinvest the expected cost savings from the 2025 Workforce Transformation into the business, including into our digital transformation initiatives.

During the year ended December 31, 2025, we recorded a pre-tax charge of $390 million, related to the 2025 Workforce Transformation, which is included in Cost of services and Selling, general and administrative expenses on our Consolidated Statements of Comprehensive Income. We have incurred a majority of the costs associated with our 2025 Workforce Transformation initiative, with the remaining costs of approximately $150 million expected to be substantially incurred by the end of the first quarter of 2026. We expect substantially all associated employee separations and related cash outflows to occur in 2026.

See Note 19 – Restructuring Costs of the Notes to the Consolidated Financial Statements for more information.

2023 Workforce Reduction

In August 2023, we implemented an initiative to reduce the size of our workforce by approximately 5,000 positions, just under 7% of our total employee base, primarily in corporate and back-office functions, and some technology roles.

During the year ended December 31, 2023, we recorded a pre-tax charge of $462 million, related to the 2023 Workforce Transformation, which is included in Cost of services and Selling, general and administrative expenses on our Consolidated Statements of Comprehensive Income.

See Note 19 – Restructuring Costs of the Notes to the Consolidated Financial Statements for more information.

One Big Beautiful Bill Act

On July 4, 2025, President Trump signed the One Big Beautiful Bill Act (the “OBBBA”) into law. The OBBBA includes numerous changes to existing tax law, including provisions providing current deductibility of certain property additions, limitations on interest deductions based on a tax EBITDA framework, and current deductibility of domestic research and development costs. These provisions were generally effective beginning in 2025 and did not have a material impact on our income tax payments or effective tax rate for the year ended December 31, 2025. We currently anticipate they will partially

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defer our income tax payments and will not have a material impact on our effective tax rate in future years. Management continues to review the OBBBA tax provisions to assess impacts to our consolidated financial statements.

Revenue Trends

In 2026, we expect Postpaid service revenues to continue to grow, primarily due to continued postpaid account and customer growth as well as postpaid Average Revenue per Account (“ARPA”) growth driven by the execution of our strategy to continuously deepen our account relationships, including growth in broadband. We expect Wholesale and other service revenues to remain relatively flat to slightly up, primarily from an increase in advertising revenues, offset by lower MVNO revenues, including lower EchoStar and TracFone MVNO revenues.

Operating Expense Trends

In 2026, we expect Total operating expenses to increase, primarily driven by higher Depreciation and amortization from assets placed into service associated with our continued build-out of our nationwide 5G network, as well as higher Cost of equipment sales, driven by higher expected unit sales from a growing customer base and higher Cost of services and Selling, general and administrative expenses, including from the result of our recently closed UScellular Acquisition.

Macroeconomic Trends

Macroeconomic trends may result in adverse impacts on our business, and we continue to monitor these potential impacts, including potential economic recession, changes in the Federal Reserve’s monetary policy, as well as geopolitical risks, including the Ukraine-Russia and Israel-Hamas wars and further escalations thereof. Such scenarios and uncertainties may affect, among others, expected credit loss activity as well as certain fair value estimates.

To date, price inflation has not had a significant impact on our operations as we have fixed rates established through long-term contracts for many of our most significant costs, including for many of our tower agreements and backhaul contracts. Similarly, our exposure to the impact of fluctuating interest rates is limited, primarily to any new debt issuances or draws on our Revolving Credit Facility (as defined below), as interest is paid on our Senior Notes at a fixed rate. We continue to monitor the impact of these trends on the payment performance of our customers.

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Results of Operations

Set forth below is a summary of our consolidated financial results:


	Year Ended December 31,			2025 Versus 2024				2024 Versus 2023
(in millions)		2025		2024		2023		$ Change		% Change		$ Change		% Change
Revenues

Postpaid revenues		$	57,932	$	52,340	$	48,692	$	5,592	11	%	$	3,648	7	%
Prepaid revenues		10,497		10,399		9,767		98		1	%	632		6	%
Wholesale and other service revenues		2,877		3,439		4,782		(562)		(16)	%	(1,343)		(28)	%

Total service revenues		71,306		66,178		63,241		5,128		8	%	2,937		5	%
Equipment revenues		15,972		14,263		14,138		1,709		12	%	125		1	%
Other revenues		1,031		959		1,179		72		8	%	(220)		(19)	%

Total revenues		88,309		81,400		78,558		6,909		8	%	2,842		4	%
Operating expenses

Cost of services, exclusive of depreciation and amortization shown separately below		11,497		10,771		11,655		726		7	%	(884)		(8)	%
Cost of equipment sales, exclusive of depreciation and amortization shown separately below		21,277		18,882		18,533		2,395		13	%	349		2	%
Selling, general and administrative		23,470		20,818		21,311		2,652		13	%	(493)		(2)	%
Impairment expense		278		—		—		278		NM		—		NM
Gain on disposal group held for sale		—		—		(25)		—		NM		25		(100)	%
Depreciation and amortization		13,508		12,919		12,818		589		5	%	101		1	%

Total operating expenses		70,030		63,390		64,292		6,640		10	%	(902)		(1)	%
Operating income		18,279		18,010		14,266		269		1	%	3,744		26	%
Other expense, net

Interest expense, net		(3,774)		(3,411)		(3,335)		(363)		11	%	(76)		2	%
Other (expense) income, net		(224)		113		68		(337)		(298)	%	45		66	%

Total other expense, net		(3,998)		(3,298)		(3,267)		(700)		21	%	(31)		1	%

Income before income taxes		14,281		14,712		10,999		(431)		(3)	%	3,713		34	%
Income tax expense		(3,289)		(3,373)		(2,682)		84		(2)	%	(691)		26	%

Net income		$	10,992	$	11,339	$	8,317	$	(347)	(3)	%	$	3,022	36	%

Statement of Cash Flows Data
Net cash provided by operating activities		$	27,950	$	22,293	$	18,559	$	5,657	25	%	$	3,734	20	%
Net cash used in investing activities		(17,607)		(9,072)		(5,829)		(8,535)		94	%	(3,243)		56	%
Net cash used in financing activities		(10,081)		(12,815)		(12,097)		2,734		(21)	%	(718)		6	%
Non-GAAP Financial Measures
Adjusted EBITDA		$	33,937	$	31,864	$	29,428	$	2,073	7	%	$	2,436	8	%
Core Adjusted EBITDA		33,924		31,771		29,116		2,153		7	%	2,655		9	%
Adjusted Free Cash Flow		17,995		17,032		13,586		963		6	%	3,446		25	%

NM - Not meaningful

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The following discussion and analysis is for the year ended December 31, 2025, compared to the same period in 2024, unless otherwise stated. For a discussion and analysis of the year ended December 31, 2024, compared to the same period in 2023, please refer to Management’s Discussion and Analysis of Financial Condition and Results of Operations included in Part II, Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on January 31, 2025.

Total revenues increased $6.9 billion, or 8%. The components of these changes are discussed below.

Postpaid revenues increased $5.6 billion, or 11%, primarily from:

•Higher average postpaid accounts, including following the acquisitions of UScellular, Metronet and Lumos; and

•Higher postpaid ARPA. See “Postpaid ARPA” in the “Performance Measures” section of this MD&A.

Prepaid revenues increased $98 million, or 1%, primarily from:

•Higher average prepaid customers, primarily from the prepaid customers acquired through the Ka’ena Acquisition; partially offset by

•Lower prepaid ARPU. See “Prepaid ARPU” in the “Performance Measures” section of this MD&A.

Wholesale and other service revenues decreased $562 million, or 16%, primarily from:

•Lower MVNO revenues, including lower EchoStar and TracFone MVNO revenues and the impact from the Ka’ena Acquisition; and

•Lower Affordable Connectivity Program revenues; partially offset by

•Higher advertising revenues, primarily from the acquisitions of Vistar and Blis.

Equipment revenues increased $1.7 billion, or 12%, primarily from:

•An increase in device sales revenue, primarily from:

•Higher average revenue per device sold, net of promotions, primarily driven by an increase in the high-end phone mix; and

•A higher number of devices sold, primarily driven by higher postpaid upgrades and following the UScellular Acquisition, partially offset by lower Assurance Wireless devices; and

•An increase in liquidation revenue, primarily due to a higher number of liquidated devices.

Other revenues were essentially flat.

Total operating expenses increased $6.6 billion, or 10%. The components of this change are discussed below.

Cost of services, exclusive of depreciation and amortization, increased $726 million, or 7% primarily from:

•Higher costs following the acquisition of the UScellular Wireless Business;

•Wholesale network access costs and amortization of customer installation fees paid to Metronet and Lumos;

•$111 million of severance and related costs associated with the 2025 Workforce Transformation;

•Higher third-party costs primarily due to higher subscribers and the launch of T-Satellite; and

•Network Restructuring Initiative costs.

Cost of equipment sales, exclusive of depreciation and amortization, increased $2.4 billion, or 13%, primarily from:

•An increase in device cost of equipment sales, primarily from:

•Higher average cost per device sold, primarily driven by an increase in the high-end phone mix; and

•A higher number of devices sold, primarily driven by higher postpaid upgrades and following the acquisition of the UScellular Wireless Business, partially offset by lower Assurance Wireless devices; and

•An increase in liquidation costs, primarily due to a higher number of liquidated devices.

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Selling, general and administrative expenses increased $2.7 billion, or 13%, primarily from:

•Higher personnel-related costs, including payroll and benefits;

•Higher advertising expenses;

•Higher costs following the UScellular Acquisition, including merger-related costs;

•Prior year recognition of $202 million of gains associated with the closing of certain spectrum exchange transactions, $105 million of legal-related insurance recoveries and a $100 million gain for the extension fee previously paid by DISH associated with the license purchase agreement for 800 MHz spectrum licenses, which was not purchased;

•$279 million of severance and related costs associated with the 2025 Workforce Transformation; and

•Higher bad debt expense driven by higher customers and device sales, including following the UScellular Acquisition; partially offset by

•A $151 million gain recognized in the current year related to the completed sale of a portion of our 3.45 GHz spectrum licenses.

Impairment expense was $278 million for the year ended December 31, 2025, due to the impairment of capitalized software development costs related to our billing system. See Note 6 – Property and Equipment of the Notes to the Consolidated Financial Statements for additional information.

Depreciation and amortization increased $589 million, or 5%, primarily from:

•Higher depreciation expense from assets acquired in the UScellular Acquisition and the continued build-out of our nationwide 5G network;

•Higher amortization of capitalized software driven by increased in-service software related to our ongoing digital transformation initiatives; and

•Higher amortization from intangible assets acquired through our acquisitions in the current year; partially offset by

•The acceleration of depreciation for certain technology assets in the prior year.

Operating income, the components of which are discussed above, increased $269 million, or 1%.

Interest expense, net increased $363 million, or 11%, primarily from higher interest expense due to higher average debt outstanding and a higher average effective interest rate.

Other (expense) income, net changed $337 million, from other net income of $113 million for the year ended December 31, 2024, to other net expense of $224 million for the year ended December 31, 2025, primarily from:

•Our proportionate share of losses from the Lumos and Metronet joint ventures recognized during the current year; and

•Prior year recognition of an $80 million gain, associated with the partial settlement of the Sprint Retirement Pension Plan retiree obligations. See Note 13 – Employee Compensation and Benefit Plans of the Notes to the Consolidated Financial Statements for additional information.

Income before income taxes, the components of which are discussed above, was $14.3 billion and $14.7 billion for the years ended December 31, 2025 and 2024, respectively.

Income tax expense decreased $84 million, or 2%, primarily from:

•Lower income before income taxes; and

•An increase in excess tax benefits related to the vesting of restricted stock awards; partially offset by

•Net tax benefits recognized in the prior year from adjustments to certain tax reserves.

Our effective tax rate was 23.0% and 22.9% for the years ended December 31, 2025 and 2024, respectively.

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Net income, the components of which are discussed above, was $11.0 billion and $11.3 billion for the years ended December 31, 2025 and 2024, respectively. Net income for the year ended December 31, 2025 included:

•Severance and related costs associated with the 2025 Workforce Transformation of $293 million, net of tax; and

•Impairment expense related to certain capitalized software development costs related to our billing system of $208 million, net of tax.

Guarantor Financial Information

Pursuant to the applicable indentures and supplemental indentures, the Senior Notes to affiliates and third parties issued by T-Mobile USA, Inc., Sprint and Sprint Capital Corporation (collectively, the “Issuers”) are fully and unconditionally guaranteed, jointly and severally, on a senior unsecured basis by T-Mobile (“Parent”) and certain of Parent’s 100% owned subsidiaries (“Guarantor Subsidiaries”).

The guarantees of the Guarantor Subsidiaries are subject to release in limited circumstances only upon the occurrence of certain customary conditions. Generally, the guarantees of the Guarantor Subsidiaries with respect to the Senior Notes issued by T-Mobile USA, Inc. (other than $3.5 billion in principal amount of Senior Notes issued in 2017 and 2018) and the credit agreement entered into by T-Mobile USA, Inc. will be automatically and unconditionally released if, immediately following such release and any concurrent releases of other guarantees, the aggregate principal amount of indebtedness of non-guarantor subsidiaries (other than certain specified subsidiaries) would not exceed $2.0 billion. The indentures, supplemental indentures and credit agreements governing the long-term debt contain covenants that, among other things, limit the ability of the Issuers or borrowers and the Guarantor Subsidiaries to incur more debt, create liens or other encumbrances, and to merge, consolidate or sell, or otherwise dispose of, substantially all of their assets.

Basis of Presentation

The following tables include summarized financial information of the obligor groups of debt issued by T-Mobile USA, Inc., Sprint and Sprint Capital Corporation. The summarized financial information of each obligor group is presented on a combined basis with balances and transactions within the obligor group eliminated. Investments in and the equity in earnings of non-guarantor subsidiaries, which would otherwise be consolidated in accordance with GAAP, are excluded from the below summarized financial information pursuant to SEC Regulation S-X Rule 13-01.

The summarized balance sheet information for the consolidated obligor group of debt issued by T-Mobile USA, Inc. is presented in the table below:


(in millions)	December 31, 2025		December 31, 2024
Current assets	$	22,347	$	16,741
Noncurrent assets	179,075		179,335
Current liabilities	22,526		18,279
Noncurrent liabilities	132,327		122,934
Due to non-guarantors	1,469		1,507

Due to related parties	2,174		2,098

The summarized results of operations information for the consolidated obligor group of debt issued by T-Mobile USA, Inc. is presented in the table below:


(in millions)	Year Ended December 31, 2025		Year Ended December 31, 2024

Total revenues	$	85,455	$	78,996
Operating income	15,080		14,463
Net income	8,620		8,360
Revenue from non-guarantors	2,691		2,619
Operating expenses to non-guarantors	2,493		2,481
Other income (expense) to non-guarantors	12		(116)

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The summarized balance sheet information for the consolidated obligor group of debt issued by Sprint is presented in the table below:


(in millions)	December 31, 2025		December 31, 2024
Current assets	$	12,459	$	10,970
Noncurrent assets	17,604		14,734
Current liabilities	16,354		12,683
Noncurrent liabilities	101,281		96,145
Due to non-guarantors (1)	17,339		21,371

Due to related parties	2,174		2,098

(1) The decrease in Due to non-guarantors was primarily driven by the impact of certain intercompany settlements during the year ended December 31, 2025.

The summarized results of operations information for the consolidated obligor group of debt issued by Sprint is presented in the table below:


(in millions)	Year Ended December 31, 2025		Year Ended December 31, 2024

Total revenues	$	839	$	330
Operating loss	(4,437)		(3,628)
Net loss	(8,958)		(8,101)


Other expense, net, to non-guarantors	(444)		(584)

The summarized balance sheet information for the consolidated obligor group of debt issued by Sprint Capital Corporation is presented in the table below:


(in millions)	December 31, 2025		December 31, 2024
Current assets	$	12,459	$	10,970
Noncurrent assets	17,604		14,734
Current liabilities	16,426		12,756
Noncurrent liabilities	97,390		92,278
Due to non-guarantors (1)	8,371		12,318

Due to related parties	2,174		2,098

(1) The decrease in Due to non-guarantors was primarily driven by the impact of certain intercompany settlements during the year ended December 31, 2025.

The summarized results of operations information for the consolidated obligor group of debt issued by Sprint Capital Corporation is presented in the table below:


(in millions)	Year Ended December 31, 2025		Year Ended December 31, 2024

Total revenues	$	839	$	330
Operating loss	(4,437)		(3,628)
Net loss	(8,935)		(8,041)


Other expense, net, to non-guarantors	(164)		(257)

Performance Measures

In managing our business and assessing financial performance, we supplement the information provided by our consolidated financial statements with other operating or statistical data and non-GAAP financial measures. These operating and financial measures are utilized by our management to evaluate our operating performance and, in certain cases, our ability to meet liquidity requirements. Although companies in the telecommunications industry may not define each of these measures in precisely the same way, we believe that these measures facilitate comparisons with other companies in the industry on key operating and financial measures.

Starting with the three months ending March 31, 2026, we will shift away from reporting total customers, including total postpaid, postpaid phone, prepaid, and broadband customers, to better align with the Company’s long-held priority on growing high-value accounts, which management believes is the best reflection of value creation versus customers. Correspondingly, with this shift, we will no longer report postpaid phone ARPU and prepaid ARPU.

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Postpaid Accounts

A postpaid account is generally defined as a billing account number that generates revenue. Postpaid accounts generally consist of customers that are qualified for postpaid service utilizing phones, 5G broadband gateways, fiber connections, mobile internet devices (including tablets and hotspots), wearables, DIGITS and other connected devices (including SyncUP and IoT), where they generally pay after receiving service.

The following table sets forth the number of ending postpaid accounts:


	As of December 31,		2025 Versus 2024		2024 Versus 2023
(in thousands)		2025	2024	2023	# Change	% Change		# Change	% Change

Postpaid accounts (1) (2) (3)		34,240	30,894	29,797	3,346	11	%	1,097	4	%

(1) In the third quarter of 2025, we acquired 1,448,000 postpaid accounts through the UScellular Acquisition, which includes the impact of certain base adjustments to align the policies of UScellular and T-Mobile.

(2) In the third quarter of 2025, we acquired 633,000 postpaid accounts from Metronet and other acquisitions.

(3) In the second quarter of 2025, we acquired 85,000 postpaid accounts from Lumos.

Postpaid Net Account Additions

The following table sets forth the number of postpaid net account additions:


	Year Ended December 31,		2025 Versus 2024		2024 Versus 2023
(in thousands)		2025	2024	2023	# Change	% Change		# Change	% Change

Postpaid net account additions		1,180	1,097	1,271	83	8	%	(174)	(14)	%

Postpaid net account additions increased 83,000, or 8%, for the year ended December 31, 2025, primarily from:

•Higher gross account additions, including fiber account additions following the acquisitions of Metronet and Lumos; partially offset by

•Higher account deactivations, including the impact from a growing account base; and

•The temporary impact of current year rate plan optimizations.

Customers

A customer is generally defined as a SIM number with a unique T-Mobile identifier that is associated with an account that generates revenue. Customers are qualified either for postpaid service utilizing phones, 5G broadband gateways, fiber connections, mobile internet devices (including tablets and hotspots), wearables, DIGITS and other connected devices (including SyncUP and IoT), where they generally pay after receiving service, or prepaid service, where they generally pay in advance of receiving service.

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The following table sets forth the number of ending customers:


	As of December 31,		2025 Versus 2024		2024 Versus 2023
(in thousands)		2025	2024	2023	# Change	% Change		# Change	% Change
Customers, end of period

Postpaid phone customers (1)		85,594	79,013	75,936	6,581	8	%	3,077	4	%
Postpaid other customers (1) (2) (3)		30,851	25,105	22,116	5,746	23	%	2,989	14	%

Total postpaid customers		116,445	104,118	98,052	12,327	12	%	6,066	6	%
Prepaid customers (1) (4)		25,943	25,410	21,648	533	2	%	3,762	17	%

Total customers		142,388	129,528	119,700	12,860	10	%	9,828	8	%
Adjustments to customers (1) (2) (3) (4) (5)		4,878	3,504	170	1,374	39	%	3,334	NM

(1)In the third quarter of 2025, we acquired 3,287,000 postpaid phone customers, 390,000 postpaid other customers, including 141,000 5G broadband customers, and 349,000 prepaid customers through the UScellular Acquisition, which includes the impact of certain base adjustments to align the policies of UScellular and T-Mobile.

(2)In the third quarter of 2025, we acquired 755,000 fiber customers from Metronet and other acquisitions.

(3)In the second quarter of 2025, we acquired 97,000 fiber customers from Lumos.

(4)In the second quarter of 2024, we acquired 3,504,000 prepaid customers through the Ka’ena Acquisition, which includes the impact of certain base adjustments to align the policies of Ka’ena and T-Mobile.

(5)In the fourth quarter of 2023, we recognized a base adjustment to increase postpaid phone customers by 20,000 and increase postpaid other customers by 150,000 due to fewer customers than expected whose service was deactivated as a result of the network shutdowns.

NM - Not meaningful

5G broadband customers included in Postpaid other customers were 7,602,000 and 5,742,000 as of December 31, 2025 and 2024, respectively. 5G broadband customers included in Prepaid customers were 848,000 and 688,000 as of December 31, 2025 and 2024, respectively. Fiber customers included in Postpaid other customers were 997,000 as of December 31, 2025.

Net Customer Additions

The following table sets forth the number of net customer additions:


	Year Ended December 31,			2025 Versus 2024		2024 Versus 2023
(in thousands)		2025	2024	2023	# Change	% Change	# Change		% Change
Net customer additions

Postpaid phone customers			3,294	3,077	3,082	217	7	%	(5)	—	%
Postpaid other customers			4,504	2,989	2,568	1,515	51	%	421	16	%

Total postpaid customers			7,798	6,066	5,650	1,732	29	%	416	7	%
Prepaid customers			184	258	282	(74)	(29)	%	(24)	(9)	%

Total net customer additions			7,982	6,324	5,932	1,658	26	%	392	7	%
Adjustments to customers (1) (2) (3) (4) (5)			4,878	3,504	170	1,374	39	%	3,334	NM

(2)In the third quarter of 2025, we acquired 755,000 fiber customers from Metronet and other acquisitions.

(3)In the second quarter of 2025, we acquired 97,000 fiber customers from Lumos.

NM - Not meaningful

Total net customer additions increased 1,658,000, or 26%, primarily from:

•Higher postpaid other net customer additions, primarily due to

•Higher net additions from mobile internet devices, including success from business customers and higher prior year deactivations of lower ARPU mobile internet devices in the educational sector activated during the COVID-19 pandemic and no longer needed;

•Higher broadband net additions; and

•Higher net additions from other connected devices; partially offset by

•Lower net additions from wearables; and

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•Higher postpaid phone net customer additions, primarily from higher gross additions, partially offset by higher churn and increased deactivations from a growing customer base; partially offset by

•Lower prepaid net customer additions, primarily from increased deactivations from a growing customer base, primarily due to the Ka’ena Acquisition, and higher prepaid to postpaid migrations, partially offset by higher gross additions.

•5G broadband net customer additions included in postpaid other net customer additions were 1,719,000 and 1,454,000 for the years ended December 31, 2025 and 2024, respectively. 5G broadband net customer additions included in prepaid net customer additions were 160,000 and 200,000 for the years ended December 31, 2025 and 2024, respectively.

•Fiber net customer additions included in postpaid other net customer additions were 136,000 for the year ended December 31, 2025.

Churn

Churn represents the number of customers whose service was deactivated as a percentage of the average number of customers during the specified period further divided by the number of months in the period. The number of customers whose service was deactivated is presented net of customers that subsequently had their service restored within a certain period of time and excludes customers who received service for less than a certain minimum period of time. We believe that churn provides management, investors and analysts with useful information to evaluate customer retention and loyalty.

The following table sets forth the churn:


		Year Ended December 31,							Bps Change 2025 Versus 2024		Bps Change 2024 Versus 2023
	2025		2024			2023
Postpaid phone churn				0.93	%		0.86	%	0.87	%	7 bps	-1 bps
Prepaid churn				2.72	%		2.73	%	2.76	%	-1 bps	-3 bps

Postpaid phone churn increased 7 basis points, primarily due to higher industry switching and from the temporary impact of current year rate plan optimizations. Prepaid churn decreased slightly.

Postpaid Average Revenue Per Account

Postpaid Average Revenue per Account (“ARPA”) represents the average monthly postpaid service revenue earned per account. Postpaid ARPA is calculated as Postpaid revenues for the specified period divided by the average number of postpaid accounts during the period, further divided by the number of months in the period. We believe postpaid ARPA provides management, investors and analysts with useful information to assess and evaluate our postpaid service revenue realization and assists in forecasting our future postpaid service revenues on a per account basis. We consider postpaid ARPA to be indicative of our revenue growth potential given the increase in the average number of postpaid phone customers per account and increases in postpaid other customers, including 5G broadband, fiber, mobile internet devices (including tablets and hotspots), wearables, DIGITS and other connected devices (including SyncUP and IoT).

The following table sets forth our operating measure ARPA:


(in dollars)	Year Ended December 31,			2025 Versus 2024						2024 Versus 2023
		2025				2024			2023	$ Change		% Change		$ Change		% Change





Postpaid ARPA		$	148.97	$	143.85		$	139.27		$	5.12	4	%	$	4.58	3	%

Postpaid ARPA increased $5.12, or 4%, primarily from:

•The positive impact from rate plan optimizations and higher fee revenue, including from the adoption of new tax and fee exclusive plans;

•An increase in customers per account, including from the continued adoption of 5G broadband and continued growth of T-Mobile for Business customers, partially offset by fiber and UScellular accounts with fewer customers per account; and

•Increased promotional activity, including the success of bundled offerings.

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Average Revenue Per User

Average Revenue per User (“ARPU”) represents the average monthly service revenue earned per customer. ARPU is calculated as service revenues for the specified period divided by the average number of customers during the period, further divided by the number of months in the period. We believe ARPU provides management, investors and analysts with useful information to assess and evaluate our service revenue per customer and assist in forecasting our future service revenues generated from our customer base. Postpaid phone ARPU excludes postpaid other customers and related revenues, which include 5G broadband, fiber, mobile internet devices (including tablets and hotspots), wearables, DIGITS and other connected devices (including SyncUP and IoT).

The following table sets forth our operating measure ARPU:


(in dollars)	Year Ended December 31,			2025 Versus 2024						2024 Versus 2023
		2025				2024			2023	$ Change		% Change		$ Change		% Change





Postpaid phone ARPU		$	50.37	$	49.35		$	48.83		$	1.02	2	%	$	0.52	1	%



Prepaid ARPU		34.14		36.06			37.92			(1.92)		(5)	%	(1.86)		(5)	%

Postpaid Phone ARPU

Postpaid phone ARPU increased $1.02, or 2%, primarily from:

•The positive impact from rate plan optimizations and higher fee revenue, including from the adoption of new tax and fee exclusive plans;

•Higher premium services, primarily high-end rate plans, net of contra revenues for content included in such plans, and discounts for specific affinity groups, such as 55+, military and first responders; partially offset by continued growth in T-Mobile for Business customers with lower ARPU given larger account sizes; and

•The impact of customers acquired in the UScellular Acquisition, which have slightly higher ARPU; partially offset by

•Increased promotional activity, including the success of bundled offerings.

Prepaid ARPU

Prepaid ARPU decreased $1.92, or 5%, primarily from the inclusion of lower ARPU prepaid customers associated with the Ka’ena Acquisition and dilution from promotional activity and rate plan mix.

Adjusted EBITDA and Core Adjusted EBITDA

Adjusted EBITDA represents earnings before Interest expense, net of Interest income, Income tax expense, Depreciation and amortization, stock-based compensation and certain expenses, gains and losses, which are not reflective of our ongoing operating performance (“Special Items”). Special Items include Sprint Merger-related costs and UScellular merger-related costs (collectively, “Merger-related costs”), costs associated with our Network Restructuring Initiative, certain legal-related expenses and recoveries, Impairment expense, restructuring costs not directly attributable to the Sprint Merger or UScellular Acquisition (including severance), and other non-core gains and losses. Core Adjusted EBITDA represents Adjusted EBITDA less device lease revenues. Adjusted EBITDA margin represents Adjusted EBITDA divided by Service revenues. Core Adjusted EBITDA margin represents Core Adjusted EBITDA divided by Service revenues.

Adjusted EBITDA, Adjusted EBITDA margin, Core Adjusted EBITDA and Core Adjusted EBITDA margin are non-GAAP financial measures utilized by our management, including our chief operating decision maker, to monitor the financial performance of our operations and allocate resources of the Company as a whole. We historically used Adjusted EBITDA, and we currently use Core Adjusted EBITDA internally as a measure to evaluate and compensate our personnel and management for their performance. We use Adjusted EBITDA and Core Adjusted EBITDA as benchmarks to evaluate our operating performance in comparison to our competitors. Management believes analysts and investors use Adjusted EBITDA and Core Adjusted EBITDA as supplemental measures to evaluate overall operating performance and to facilitate comparisons with other wireless communications and broadband services companies because they are indicative of our ongoing operating performance and trends by excluding the impact of interest expense from financing, non-cash depreciation and amortization from capital investments, non-cash stock-based compensation, and Special Items. Management believes analysts and investors use Core Adjusted EBITDA because it normalizes for the transition in the Company’s device financing strategy, by excluding the impact of device lease revenues from Adjusted EBITDA, to align with the exclusion of the related depreciation expense on leased devices from Adjusted EBITDA. Adjusted EBITDA, Adjusted EBITDA margin, Core Adjusted EBITDA and Core Adjusted

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EBITDA margin have limitations as analytical tools and should not be considered in isolation or as substitutes for income from operations, net income or any other measure of financial performance reported in accordance with GAAP.

The following table illustrates the calculation of Adjusted EBITDA and Core Adjusted EBITDA and reconciles Adjusted EBITDA and Core Adjusted EBITDA to Net income, which we consider to be the most directly comparable GAAP financial measure:


	Year Ended December 31,					2025 Versus 2024							2024 Versus 2023
(in millions, except percentages)		2025	2024						2023	$ Change			% Change		$ Change		% Change
Net income			$	10,992		$	11,339			$	8,317		$	(347)	(3)	%	$	3,022	36	%
Adjustments:


Interest expense, net			3,774			3,411				3,335			363		11	%	76		2	%


Other expense (income), net			224			(113)				(68)			337		(298)	%	(45)		66	%
Income tax expense			3,289			3,373				2,682			(84)		(2)	%	691		26	%
Operating income			18,279			18,010				14,266			269		1	%	3,744		26	%
Depreciation and amortization			13,508			12,919				12,818			589		5	%	101		1	%


Stock-based compensation (1)			772			586				644			186		32	%	(58)		(9)	%
Merger-related costs, net (2)			263			147				1,034			116		79	%	(887)		(86)	%
Network Restructuring Initiative costs			93			—				—			93		NM		—		NM



Legal-related expenses (recoveries), net (3)			16			(89)				(42)			105		(118)	%	(47)		112	%
Impairment expense			278			—				—			278		NM		—		NM
Gain on disposal group held for sale			—			—				(25)			—		NM		25		(100)	%

Other, net (4)			728			291				733			437		150	%	(442)		(60)	%
Adjusted EBITDA			33,937			31,864				29,428			2,073		7	%	2,436		8	%
Lease revenues			(13)			(93)				(312)			80		(86)	%	219		(70)	%
Core Adjusted EBITDA			$	33,924		$	31,771			$	29,116		$	2,153	7	%	$	2,655	9	%
Net income margin (Net income divided by Service revenues)			15		%	17		%		13		%			-200 bps				400 bps
Adjusted EBITDA margin (Adjusted EBITDA divided by Service revenues)			48		%	48		%		47		%			— bps				100 bps
Core Adjusted EBITDA margin (Core Adjusted EBITDA divided by Service revenues)			48		%	48		%		46		%			— bps				200 bps

T-Mobile US, Inc. 10-K