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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q


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

For the quarterly period ended March 31, 2026


☐	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: 1-09447

KAISER ALUMINUM CORPORATION

(Exact name of registrant as specified in its charter)


Delaware		94-3030279
(State of incorporation)		(I.R.S. Employer Identification No.)


1550 West McEwen Drive, Suite 500
Franklin, Tennessee		37067
(Address of principal executive offices)		(Zip Code)

(629) 252-7040

(Registrant’s telephone number, including area code)

(Former name, former address and former fiscal year, if changed since last report)

Securities registered pursuant to Section 12(b) of the Act:


Title of each class	Trading symbol	Name of each exchange on which registered
Common stock, par value $0.01 per share	KALU	Nasdaq Global Select Market

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, 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 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	☐

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 is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of April 20, 2026, there were 16,340,606 shares of common stock of the registrant outstanding.

COMMONLY USED OR DEFINED TERMS


Term	Definition
Adjusted EBITDA	Earnings before interest, taxes, depreciation and amortization adjusted for non-run-rate items
Aero/HS Products	2000, 7000 and certain 6000 series alloys products used in the Aerospace, Defense, Space and other end markets requiring high strength applications
Alloy(s)	Certain metals such as copper, zinc, magnesium, manganese and silicon added to primary aluminum to obtain certain attributes
AOCI	Accumulated other comprehensive income (loss)
ASC	Accounting Standards Codification
ASU	Accounting Standards Update
Automotive Extrusions	6000 series extruded aluminum products used in automotive applications
COGS	Cost of products sold, excluding depreciation and amortization
Form 10-Q	This Quarterly Report on Form 10-Q
GAAP	United States Generally Accepted Accounting Principles
GE Products	6000 series alloys products used in the General Engineering end markets
LME	London Metal Exchange
Metal Price Lag	Management’s estimate of the financial impact resulting from the timing difference between aluminum prices included within Hedged Cost of Alloyed Metal and the weighted average market price for aluminum during the period, based on MWTP (defined below), multiplied by our shipment volume during the periods. Metal Price Lag will generally increase our earnings in times of rising primary aluminum prices and decrease our earnings in times of declining primary aluminum prices.
MWTP	Midwest Transaction Price is equal to the LME aluminum price plus a Midwest premium
Newark	Kaiser Aluminum manufacturing facility located in Heath, Ohio, a suburb of Newark, Ohio
OPEB	Other Post Employment Benefits
Packaging	3000 and 5000 series alloys products used in the beverage and food packaging end markets
Revolving Credit Facility	Revolving credit facility with Wells Fargo Bank, National Association, as administrative agent, and the other financial institutions party thereto
Salaried VEBA	Salaried Voluntary Employees' Beneficiary Association
SEC	U.S. Securities and Exchange Commission
Senior Notes	Collectively, the fixed-rate unsecured notes we issued during the years ended December 31, 2019, 2021, and 2025 at the following interest rates and aggregate principal amounts, respectively: (i) 4.625% and $500.0 million (issued in 2019; redeemed in full on November 6, 2025); (ii) 4.50% and $550.0 million (issued in 2021 and maturing in 2031); and (iii) 5.875% and $500.0 million (issued in 2025 and maturing in 2034)
SOFR	Secured Overnight Financing Rate
Trentwood	Kaiser Aluminum manufacturing facility located in Spokane Valley, Washington
Warrick	Kaiser Aluminum manufacturing facility located in Newburgh, Indiana, in the county of Warrick

TABLE OF CONTENTS


PART I
Item 1. Financial Statements		1
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations		21
Item 3. Quantitative and Qualitative Disclosures About Market Risk		29
Item 4. Controls and Procedures		30

PART II
Item 1. Legal Proceedings		31
Item 1A. Risk Factors		31
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds		31
Item 3. Defaults Upon Senior Securities		31
Item 4. Mine Safety Disclosures		31
Item 5. Other Information		31
Item 6. Exhibits		32

SIGNATURES		33

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

PART I – FINANCIAL INFORMATION

Item 1. Financial Statements

CONSOLIDATED BALANCE SHEETS (UNAUDITED)


	As of March 31, 2026			As of December 31, 2025
	(In millions of dollars, except share and per share amounts)
ASSETS
Current assets:
Cash and cash equivalents	$	30.0		$	7.0
Receivables, net		528.6			423.3
Contract assets		75.9			63.4
Inventories		799.0			725.2
Prepaid expenses and other current assets		53.9			42.6
Total current assets		1,487.4			1,261.5
Property, plant and equipment, net		1,139.5			1,145.2
Operating lease assets		24.6			22.4
Deferred tax assets, net		—			0.2
Intangible assets, net		39.9			41.0
Goodwill		18.8			18.8
Other assets		79.7			75.7
Total assets	$	2,789.9		$	2,564.8
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities:
Accounts payable	$	494.1		$	274.6
Accrued salaries, wages and related expenses		51.5			61.3
Other accrued liabilities		56.3			91.3
Total current liabilities		601.9			427.2
Long-term portion of operating lease liabilities		22.5			21.7
Pension and OPEB		72.9			73.4
Deferred tax liabilities		93.5			75.4
Long-term liabilities		84.0			81.4
Long-term debt, net		1,037.8			1,059.6
Total liabilities		1,912.6			1,738.7
Commitments and contingencies – Note 6
Stockholders’ equity:
Preferred stock, 5,000,000 shares authorized at both March 31, 2026 and December 31, 2025; no shares were issued and outstanding at March 31, 2026 and December 31, 2025		—			—
Common stock, par value $0.01, 90,000,000 shares authorized at both March 31, 2026 and December 31, 2025; 23,175,410 shares issued and 16,340,124 shares outstanding at March 31, 2026; 23,045,729 shares issued and 16,210,443 shares outstanding at December 31, 2025		0.2			0.2
Additional paid in capital		1,129.6			1,132.5
Retained earnings		191.4			142.5
Treasury stock, at cost, 6,835,286 shares at both March 31, 2026 and December 31, 2025		(475.9	)		(475.9	)
AOCI		32.0			26.8
Total stockholders’ equity		877.3			826.1
Total liabilities and stockholders' equity	$	2,789.9		$	2,564.8

The accompanying notes to interim consolidated financial statements are an integral part of these statements.

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

STATEMENTS OF CONSOLIDATED INCOME (UNAUDITED)



	Quarter Ended March 31,
	2026			2025
	(In millions of dollars, except share and per share amounts)
Net sales	$	1,106.8		$	777.4
Costs and expenses:
Cost of products sold, excluding depreciation and amortization		943.2			673.4
Depreciation and amortization		30.4			30.0
Selling, general, administrative, research and development		35.4			30.8
Restructuring costs		—			1.8
Total costs and expenses		1,009.0			736.0
Operating income		97.8			41.4
Other expense:
Interest expense		(14.4	)		(11.2	)
Other expense, net – Note 8		(1.0	)		(1.4	)
Income before income taxes		82.4			28.8
Income tax provision		(19.9	)		(7.2	)
Net income	$	62.5		$	21.6

Net income per common share:
Basic	$	3.85		$	1.34
Diluted	$	3.71		$	1.31
Weighted-average number of common shares outstanding (in thousands):
Basic		16,248			16,116
Diluted		16,844			16,399

The accompanying notes to interim consolidated financial statements are an integral part of these statements.

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (UNAUDITED)


	Quarter Ended March 31,
	2026		2025
	(In millions of dollars)
Net income	$	62.5	$	21.6
Other comprehensive income, net of tax – Note 7:
Defined benefit plans		0.2		0.1
Cash flow hedges		5.0		2.5
Other comprehensive income, net of tax		5.2		2.6
Comprehensive income	$	67.7	$	24.2

The accompanying notes to interim consolidated financial statements are an integral part of these statements.

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

STATEMENTS OF CONSOLIDATED STOCKHOLDERS’ EQUITY (UNAUDITED)

Quarter Ended March 31, 2026


	Common Shares Outstanding1			Common Stock		Additional Paid in Capital			Retained Earnings			Treasury Stock			AOCI		Total
	(In millions of dollars, except share and per share amounts)
BALANCE, December 31, 2025		16,210,443		$	0.2	$	1,132.5		$	142.5		$	(475.9	)	$	26.8	$	826.1
Net income		—			—		—			62.5			—			—		62.5
Other comprehensive income, net of tax		—			—		—			—			—			5.2		5.2
Common shares issued (including impacts from Long-Term Incentive programs)		199,737			—		—			—			—			—		—
Cancellation of shares to cover tax withholdings upon common shares issued		(70,056	)		—		(8.8	)		—			—			—		(8.8	)
Cash dividends declared2		—			—		—			(13.6	)		—			—		(13.6	)
Amortization of unearned equity compensation		—			—		5.9			—			—			—		5.9
BALANCE, March 31, 2026		16,340,124		$	0.2	$	1,129.6		$	191.4		$	(475.9	)	$	32.0	$	877.3

At March 31, 2026, 374,182 shares were available for awards under the Kaiser Aluminum Corporation 2021 Equity and Incentive Compensation Plan, as amended and restated.

Dividends declared per common share were $0.77 for the quarter ended March 31, 2026.

The accompanying notes to interim consolidated financial statements are an integral part of these statements.

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

STATEMENTS OF CONSOLIDATED STOCKHOLDERS’ EQUITY CONTINUED (UNAUDITED)

Quarter Ended March 31, 2025


	Common Shares Outstanding			Common Stock		Additional Paid in Capital			Retained Earnings			Treasury Stock			AOCI		Total
	(In millions of dollars, except share and per share amounts)
BALANCE, December 31, 2024		16,095,898		$	0.2	$	1,117.0		$	81.3		$	(475.9	)	$	20.5	$	743.1
Net income		—			—		—			21.6			—			—		21.6
Other comprehensive income, net of tax		—			—		—			—			—			2.6		2.6
Common shares issued (including impacts from Long-Term Incentive programs)		84,115			—		—			—			—			—		—
Cancellation of shares to cover tax withholdings upon common shares issued		(25,637	)		—		(1.8	)		—			—			—		(1.8	)
Cash dividends declared1		—			—		—			(12.9	)		—			—		(12.9	)
Amortization of unearned equity compensation		—			—		4.2			—			—			—		4.2
BALANCE, March 31, 2025		16,154,376		$	0.2	$	1,119.4		$	90.0		$	(475.9	)	$	23.1	$	756.8

Dividends declared per common share were $0.77 for the quarter ended March 31, 2025.

The accompanying notes to interim consolidated financial statements are an integral part of these statements.

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

STATEMENTS OF CONSOLIDATED CASH FLOWS (UNAUDITED)


	Quarter Ended March 31,
	2026			2025
	(In millions of dollars)
Cash flows from operating activities1:
Net income	$	62.5		$	21.6
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation of property, plant and equipment		29.3			28.9
Amortization of definite-lived intangible assets		1.1			1.1
Amortization of debt issuance costs		0.7			0.5
Deferred income taxes		16.8			6.4
Non-cash equity compensation		5.9			4.2
Loss on disposition of property, plant and equipment		0.3			—
Non-cash postretirement and postemployment defined benefit plan cost		2.1			2.3
Changes in operating assets and liabilities:
Receivables		(105.3	)		(48.0	)
Contract assets		(12.5	)		5.5
Inventories		(73.8	)		29.5
Prepaid expenses and other current assets		(1.6	)		0.2
Accounts payable		217.6			20.3
Accrued liabilities		(46.2	)		(14.3	)
Annual variable cash contributions to Salaried VEBA		(2.9	)		(0.7	)
Long-term assets and liabilities, net		(6.1	)		(0.5	)
Net cash provided by operating activities		87.9			57.0
Cash flows from investing activities1:
Capital expenditures		(19.4	)		(38.2	)
Net cash used in investing activities		(19.4	)		(38.2	)
Cash flows from financing activities1:
Borrowings under the Revolving Credit Facility		71.5			42.5
Repayment of borrowings under the Revolving Credit Facility		(93.8	)		(42.5	)
Repayment of finance lease		(0.7	)		(0.7	)
Cancellation of shares to cover tax withholdings upon common shares issued		(8.8	)		(1.8	)
Cash dividends and dividend equivalents paid		(13.6	)		(12.9	)
Net cash used in financing activities		(45.4	)		(15.4	)
Net increase in cash, cash equivalents and restricted cash during the period		23.1			3.4
Cash, cash equivalents and restricted cash at beginning of period		26.9			37.9
Cash, cash equivalents and restricted cash at end of period	$	50.0		$	41.3

See Note 11 for supplemental cash flow information.

The accompanying notes to interim consolidated financial statements are an integral part of these statements.

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS - UNAUDITED

NOTES INDEX


Note 1	Basis of Presentation and Recent Accounting Pronouncements	8
Note 2	Supplemental Balance Sheet Information	10
Note 3	Employee Benefits	11
Note 4	Derivatives, Hedging Programs and Other Financial Instruments	12
Note 5	Debt and Credit Facility	14
Note 6	Commitments and Contingencies	15
Note 7	Accumulated Other Comprehensive Income	16
Note 8	Other Expense, Net	17
Note 9	Income Tax Matters	17
Note 10	Earnings Per Share	17
Note 11	Supplemental Cash Flow Information	18
Note 12	Business, Product, and Geographical Area Information	18
Note 13	Subsequent Events	20

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

1. Basis of Presentation and Recent Accounting Pronouncements

This Form 10-Q should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. Unless the context otherwise requires, references in these notes to interim consolidated financial statements - unaudited to “Kaiser,” “we,” “us,” “our,” “the Company” and “our Company” refer collectively to Kaiser Aluminum Corporation and its subsidiaries.

Principles of Consolidation and Basis of Presentation. The accompanying unaudited consolidated financial statements include the accounts of our wholly owned subsidiaries and are prepared in accordance with GAAP and the rules and regulations of the SEC applicable for interim periods and, therefore, do not include all information and footnotes required by GAAP for complete financial statements. In management’s opinion, all adjustments (which include normal recurring adjustments) considered necessary for a fair presentation have been included. We have reclassified certain items in prior periods to conform to current classifications. The results of operations for our interim periods are not necessarily indicative of the results of operations that may be achieved for the entire 2026 fiscal year. The financial information as of December 31, 2025 is derived from our audited consolidated financial statements and footnotes included in our Annual Report on Form 10-K for the year ended December 31, 2025.

Use of Estimates in the Preparation of Financial Statements. The preparation of financial statements in accordance with GAAP requires the use of estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities known to exist as of the date the financial statements are published and the reported amounts of revenues and expenses during the reporting period. Uncertainties with respect to such estimates and assumptions are inherent in the preparation of our consolidated financial statements; accordingly, it is possible that the actual results could differ from these estimates and assumptions, which could have a material effect on the reported amounts of our consolidated financial position and results of operations.

Adoption of New Accounting Pronouncements

Accounting for Internal-Use Software. In September 2025, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2025-06 (“ASU 2025-06”), Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which removes all references to software development stages so that the guidance is neutral to different software development methods. We early adopted ASU 2025-06 as of January 1, 2026 using the prospective transition approach. The adoption of ASU 2025-06 did not have a material impact on our consolidated financial statements.

Accounting Pronouncements Issued But Not Yet Adopted

Disclosure Improvements. In October 2023, the FASB issued ASU No. 2023-06 (“ASU 2023-06”), Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. The guidance amends GAAP to reflect updates and simplifications to certain disclosure requirements referred to the FASB by the SEC. The amendments in ASU 2023-06 will become effective on the date which the SEC’s removal of the related disclosure becomes effective. If by June 30, 2027, the SEC does not remove the related disclosure, the pending amendment will be removed from ASC 2023-06 and it will not be effective. Adoption of ASU 2023-06 is expected to modify the disclosure and presentation requirements only and is not expected to have a material impact on our consolidated financial statements.

Disaggregation of Income Statement Expenses. In November 2024, the FASB issued ASU No. 2024-03 (“ASU 2024-03”), Disaggregation of Income Statement Expenses. The guidance requires additional, disaggregated disclosure about certain income statement expense line items. The amendments in ASU 2024-03 are effective for annual reporting periods beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027, with early adoption permitted, and is required to be applied prospectively with the option of retrospective application. We plan to adopt the provisions of ASU 2024-03 prospectively in the fourth quarter of fiscal 2027 and continue to evaluate the disclosure requirements related to the new standard.

Hedge Accounting Improvements. In November 2025, the FASB issued ASU No. 2025-09 (“ASU 2025-09”), Derivatives and Hedging (Topic 815): Hedge Accounting Improvements. The guidance introduces targeted refinements intended to improve the operability of hedge accounting and better align financial reporting with risk management activities, including greater flexibility in hedge designation and clarifications for certain instruments. ASU 2025-09 is effective for fiscal years beginning after December 15, 2026, with early adoption permitted. We are currently evaluating the impact of this pronouncement on our consolidated financial statements.

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

Government Grants. In December 2025, the FASB issued ASU No. 2025-10 (“ASU 2025-10”), Government Grants (Topic 832): Accounting for Government Grants Received by Business Entities, to establish authoritative guidance on the accounting for government grants received by business entities. ASU 2025-10 is effective for fiscal years beginning after December 15, 2028, with early adoption permitted, and is required to be applied using a modified prospective, modified retrospective, or full retrospective transition method. We are currently evaluating the impact of this pronouncement on our consolidated financial statements.

Interim Reporting Narrow-Scope Improvements. In December 2025, the FASB issued ASU No. 2025-11 (“ASU 2025-11”), Interim Reporting (Topic 270): Narrow-Scope Improvements, which clarifies the scope, form and content, and required disclosures in interim financial statements prepared under GAAP. ASU 2025-11 enhances guidance for entities that issue condensed interim statements and reinstates a principles-based requirement to disclose material events since the last annual period. ASU 2025-11 is effective for interim periods in fiscal years beginning after December 15, 2027, with early adoption permitted and retrospective application optional. We are currently evaluating the impact of this standard on our consolidated financial statements.

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

2. Supplemental Balance Sheet Information


	As of March 31, 2026			As of December 31, 2025
	(In millions of dollars)
Receivables, Net
Accounts receivable	$	529.2		$	423.9
Allowance for doubtful receivables		(0.6	)		(0.6	)
Receivables, net	$	528.6		$	423.3

Inventories
Finished products	$	134.0		$	156.1
Work-in-process		316.6			316.7
Raw materials		332.1			236.2
Operating supplies		16.3			16.2
Inventories	$	799.0		$	725.2

Property, Plant and Equipment, Net
Land and improvements	$	44.1		$	38.2
Buildings and leasehold improvements		303.4			302.6
Machinery and equipment		1,594.3			1,586.7
Construction in progress		74.8			66.7
Property, plant and equipment, gross		2,016.6			1,994.2
Accumulated depreciation and amortization		(877.2	)		(849.1	)
Land held for sale		0.1			0.1
Property, plant and equipment, net	$	1,139.5		$	1,145.2

Other Assets
Restricted cash – Note 11	$	20.0		$	19.9
Long-term replacement parts		32.3			28.5
Net assets of Salaried VEBA		9.9			9.7
Other		17.5			17.6
Other assets	$	79.7		$	75.7
.
Other Accrued Liabilities
Uncleared cash disbursements	$	1.2		$	45.8
Accrued income taxes and other taxes payable		15.0			7.8
Accrued annual contribution to Salaried VEBA	—				2.9
Accrued interest		10.8			6.9
Current operating lease liabilities		5.9			4.8
Current finance lease liabilities		3.4			2.3
Current deferred compensation plan liabilities – Note 3		1.0			1.2
Other – Note 4		19.0			19.6
Other accrued liabilities	$	56.3		$	91.3

Long-Term Liabilities
Workers' compensation accrual	$	25.5		$	26.0
Long-term environmental accrual – Note 6		17.3			17.4
Other long-term liabilities		41.2			38.0
Long-term liabilities	$	84.0		$	81.4

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

3. Employee Benefits

Deferred Compensation Plan

Assets of our deferred compensation plan are included in Other assets. Such assets, representing diversified investment funds in registered investment companies, are classified within Level 1 of the fair value hierarchy and are measured and recorded at fair value based on their quoted market prices. These assets are accounted for as equity investments, with changes in fair value recorded within Other expense, net (see Note 8). Offsetting liabilities relating to the deferred compensation plan are included in Other accrued liabilities and Long-term liabilities.

Short-Term Incentive Plans

As of March 31, 2026, we had a liability of $11.8 million recorded within Accrued salaries, wages and related expenses for estimated probable future payments under the 2026 short-term incentive plans.

Postretirement and Postemployment Benefit Plans

The following table presents the total expense related to all postretirement and postemployment benefit plans (in millions of dollars):


	Quarter Ended March 31,
	2026		2025
Defined contribution plans1	$	6.0	$	6.0
Deferred compensation plan2		0.1		0.2
Multiemployer pension plans1		1.5		1.5
Net periodic postretirement and postemployment benefit cost relating to defined benefit plans3		2.1		2.3
Total	$	9.7	$	10.0

Substantially all of these charges related to employee benefits are in COGS with the remaining balance in Selling, general, administrative, research, and development (“SG&A and R&D”) in our Statements of Consolidated Income.

Deferred compensation plan expense is included within SG&A and R&D in our Statements of Consolidated Income.

The current service cost component of Net periodic postretirement and postemployment benefit cost relating to both the pension plans and the OPEB plan is included within COGS in our Statements of Consolidated Income for all periods presented. All other components are included within Other expense, net, in our Statements of Consolidated Income.

Components of Net Periodic Postretirement and Postemployment Benefit Cost. The following tables present the components of Net periodic postretirement and postemployment benefit cost relating to our defined benefit plans (in millions of dollars):


	Pension Plans						OPEB						Salaried VEBA
	Quarter Ended March 31,						Quarter Ended March 31,						Quarter Ended March 31,
	2026			2025			2026			2025			2026			2025
Service cost	$	0.8		$	0.9		$	0.2		$	0.2		$	—		$	—
Interest cost		0.5			0.4			0.9			0.9			0.5			0.5
Expected return on plan assets		(0.5	)		(0.4	)		—			—			(0.6	)		(0.5	)
Amortization of prior service cost1		0.2			0.2			—			—			0.7			0.7
Amortization of net actuarial gain		—			—			(0.3	)		(0.5	)		(0.3	)		(0.1	)
Total net periodic postretirement and postemployment benefit cost	$	1.0		$	1.1		$	0.8		$	0.6		$	0.3		$	0.6

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

We amortize prior service cost on a straight-line basis over the average remaining years of service of the active plan participants.

4. Derivatives, Hedging Programs and Other Financial Instruments

Overview

We utilize derivative instruments to manage exposure to: (i) metal price risk related to aluminum and certain alloys used as raw material for our fabrication operations; (ii) energy price risk related to natural gas and electricity used in our production processes; and (iii) foreign currency exchange rate risk related to certain equipment and service agreements. We do not use derivative financial instruments for trading or other speculative purposes. Hedging transactions are executed centrally and are overseen by a committee (“Hedging Committee”) composed of key operations and finance personnel from the management team. Management reviews the scope of the Hedging Committee’s activities with our Board of Directors.

We are exposed to counterparty credit risk on all of our derivative instruments. Our counterparties are major investment-grade financial institutions or trading companies, and our hedging transactions are governed by negotiated International Swaps and Derivatives Association Master Agreements, which generally require collateral to be posted by our counterparties above specified credit thresholds, which may adjust up or down based on changes in counterparty credit ratings. As a result, we believe the risk of loss is remote and contained. The aggregate fair value of our derivative instruments that were in a net liability position was $1.6 million and $0.1 million at March 31, 2026 and December 31, 2025, respectively, and we had no collateral posted as of those dates.

In addition, our firm-price customer sales commitments create incremental customer credit risk related to metal price movements. Under certain circumstances, we mitigate this risk by periodically requiring cash collateral to be posted by our customers, which we classify as deferred revenue and include as a component of Other accrued liabilities. We had no cash collateral posted by our customers at both March 31, 2026 and December 31, 2025.

The above described derivative instruments are typically designated as cash flow hedges. Unrealized gains and losses associated with our cash flow hedges are deferred in Other comprehensive income, net of tax, and reclassified to COGS when such hedges settle or when it is probable that the original forecasted transactions will not occur by the end of the originally specified time period. See Note 7 for the total amount of gain or loss on derivative instruments designated and qualifying as cash flow hedging instruments that was reported in AOCI, as well as the related reclassifications into earnings and tax effects. Cumulative gains and losses related to cash flow hedges are reclassified out of AOCI and recorded within COGS when the associated hedged commodity purchases impact earnings.

From time to time, we enter into commodity and foreign currency forward contracts that are not designated as hedging instruments to mitigate certain short‑term impacts, as identified. The gain or loss on these commodity and foreign currency derivatives is recognized within COGS and Other expense, net, respectively. As of March 31, 2026 and December 31, 2025, we had no outstanding non-designated derivative hedge positions.

Notional Amount of Derivative Contracts

The following table summarizes our derivative positions at March 31, 2026:


Aluminum	Maturity Period	Notional Amount of Contracts (mmlbs)
Fixed price purchase contracts for LME	April 2026 through July 2027		72.5
Fixed price sale contracts for LME	April 2026 through April 2027		10.1
Fixed price purchase contracts for MWTP	April 2026 through July 2027		72.6
Fixed price sale contracts for MWTP	April 2026 through April 2027		10.2


Alloying Metals	Maturity Period	Notional Amount of Contracts (mmlbs)
Fixed price purchase contracts	April 2026 through December 2027		6.2


Natural Gas	Maturity Period	Notional Amount of Contracts (mmbtu)
Fixed price purchase contracts	April 2026 through December 2028		3,450,000

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED


Electricity	Maturity Period	Notional Amount of Contracts (Mwh)
Fixed price purchase contracts	April 2026 through December 2027		316,228


Euro	Maturity Period	Notional Amount of Contracts (in millions of Euros)
Fixed price forward purchase contracts	April 2026 through July 2027	€	0.6

(Gain) Loss on Derivative Contracts

The following table summarizes the amount of (gain) loss on derivative contracts recorded within our Statements of Consolidated Income in COGS (in millions of dollars):


	Quarter Ended March 31,
	2026			2025
Total of income and expense line items presented in our Statements of Consolidated Income in which the effects of hedges are recorded:
Cash flow hedges	$	943.2		$	673.4

(Gain) loss recognized in our Statements of Consolidated Income related to cash flow hedges:
Aluminum	$	(8.5	)	$	(5.2	)
Alloying Metals		(0.5	)		(0.4	)
Natural gas		(0.3	)		—
Foreign exchange contracts		—			0.1
Total gain recognized in our Statements of Consolidated Income related to cash flow hedges	$	(9.3	)	$	(5.5	)

Fair Values of Derivative Contracts

The fair values of our derivative contracts are based upon trades in liquid markets. Valuation model inputs can be verified, and valuation techniques do not involve significant judgment. The fair values of such derivatives are classified within Level 2 of the fair value hierarchy.

All of our derivative contracts with counterparties are subject to enforceable master netting arrangements. We reflect the fair value of our derivative contracts on a gross basis on our Consolidated Balance Sheets. The following table presents the fair value of our derivative financial instruments (in millions of dollars):


	As of March 31, 2026								As of December 31, 2025
	Assets		Liabilities			Net Amount			Assets		Liabilities			Net Amount
Cash Flow Hedges:
Aluminum –
Fixed price purchase contracts for LME	$	8.7	$	(0.1	)	$	8.6		$	2.6	$	—		$	2.6
Fixed price sale contracts for LME		—		(0.8	)		(0.8	)		—		(0.8	)		(0.8	)
Fixed price purchase contracts for MWTP		7.0		—			7.0			3.8		(0.1	)		3.7
Fixed price sale contracts for MWTP		—		(0.5	)		(0.5	)		—		(1.6	)		(1.6	)
Alloying Metals – Fixed price purchase contracts		1.9		—			1.9			2.4		—			2.4
Natural gas – Fixed price purchase contracts		0.7		(2.3	)		(1.6	)		0.7		(1.3	)		(0.6	)
Electricity – Fixed price purchase contracts		1.0		(3.4	)		(2.4	)		—		—			—
Foreign currency – Fixed price forward contracts		—		—			—			0.1		—			0.1
Total	$	19.3	$	(7.1	)	$	12.2		$	9.6	$	(3.8	)	$	5.8

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

The following table presents the total amounts of derivative assets and liabilities on our Consolidated Balance Sheets (in millions of dollars):


	As of March 31, 2026			As of December 31, 2025
Derivative assets:
Prepaid expenses and other current assets	$	18.0		$	8.3
Other assets		1.3			1.3
Total derivative assets	$	19.3		$	9.6
Derivative liabilities:
Other accrued liabilities	$	(5.0	)	$	(3.1	)
Long-term liabilities		(2.1	)		(0.7	)
Total derivative liabilities	$	(7.1	)	$	(3.8	)

Fair Values of Other Financial Instruments

All Other Financial Assets and Liabilities. We believe that the fair values of our financial assets and liabilities (accounts receivable, contract assets, current assets, accounts payable, and accrued liabilities) approximate their respective fair values due to their short maturities and nominal credit risk.

5. Debt and Credit Facility

Senior Notes

At March 31, 2026 and December 31, 2025, we had outstanding fixed-rate unsecured Senior Notes with varying maturity dates. The stated interest rates and aggregate principal amounts of such Senior Notes were, respectively: (i) 4.50% and $550.0 million (“4.50% Senior Notes”) and (ii) 5.875% and $500.0 million (“5.875% Senior Notes”). Our Senior Notes do not require us to make any mandatory redemptions or sinking fund payments. The following table summarizes key details of our Senior Notes:


				Outstanding (in millions of dollars)
	Issuance Date	Maturity	Effective Interest Rate	As of March 31, 2026			As of December 31, 2025
4.50% Senior Notes	May 2021	June 2031	4.7%	$	550.0		$	550.0
5.875% Senior Notes	November 2025	March 2034	6.1%		500.0			500.0
Total debt					1,050.0			1,050.0
Unamortized issuance costs					(12.2	)		(12.7	)
Total carrying amount				$	1,037.8		$	1,037.3

The following table presents the fair value of our outstanding Senior Notes, which are Level 1 liabilities (in millions of dollars):


	As of March 31, 2026		As of December 31, 2025
4.50% Senior Notes	$	519.6	$	531.4
5.875% Senior Notes	$	490.9	$	501.6

Revolving Credit Facility

In October 2019, we entered into a Revolving Credit Facility. Joining us as borrowers under the Revolving Credit Facility are four of our wholly owned domestic operating subsidiaries: (i) Kaiser Aluminum Investments Company; (ii) Kaiser Aluminum Fabricated Products, LLC; (iii) Kaiser Aluminum Washington, LLC; and (iv) Kaiser Aluminum Warrick, LLC.

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

As amended in October 2025, the Revolving Credit Facility is set to mature in October 2030 and contains a maximum commitment amount of $575.0 million (of which up to a maximum of $50.0 million may be utilized for letters of credit). The facility includes an accordion feature that allows for an increase in total revolving commitments of up to $200.0 million, plus an additional amount for a first-in last-out tranche, subject to lender approval and other customary conditions. The amount we can borrow under the Revolving Credit Facility is determined by the value of our eligible accounts receivable and inventory and certain other assets, which serve as collateral for the Revolving Credit Facility. Borrowings under the amended Revolving Credit Facility bear interest at a rate equal to either a base rate or the SOFR, plus, in each case, a specified variable percentage between 125 - 150 basis points for SOFR loans (or 25 - 50 basis points for base rate loans) determined by reference to the then-remaining borrowing availability under the Revolving Credit Facility and, in certain instances, a fixed margin. Outstanding borrowings under the Revolving Credit Facility are reported within Long-term debt, net, on our Consolidated Balance Sheets. We had no outstanding borrowings under the Revolving Credit Facility as of March 31, 2026 and $22.3 million of outstanding borrowings under the Revolving Credit Facility as of December 31, 2025.

The following table summarizes availability and usage of our Revolving Credit Facility as determined by a borrowing base calculated as of March 31, 2026 (in millions of dollars):


Revolving Credit Facility borrowing commitment	$	575.0
Borrowing base availability	$	575.0
Less: Outstanding borrowings under Revolving Credit Facility		—
Less: Outstanding letters of credit under Revolving Credit Facility		(8.7	)
Remaining borrowing availability	$	566.3

Interest Expense

The following table presents interest expense relating to our Senior Notes and Revolving Credit Facility (in millions of dollars):


	Quarter Ended March 31,
	2026			2025
Senior Notes interest expense, including debt issuance cost amortization	$	14.0		$	12.4
Revolving Credit Facility interest expense, including commitment fees and finance cost amortization		0.6			0.6
Interest expense on finance lease liabilities		0.2			0.2
Interest expense capitalized as construction in progress		(0.4	)		(2.0	)
Total interest expense	$	14.4		$	11.2

6. Commitments and Contingencies

Commitments. We have a variety of financial commitments, including purchase agreements, forward foreign exchange and forward sales contracts, indebtedness and letters of credit (see Note 4 and Note 5).

Environmental Contingencies. We are subject to several environmental laws and regulations, potential fines or penalties assessed for alleged breaches of such laws and regulations, and potential claims based upon such laws and regulations. We are also subject to legacy environmental contingencies related to activities that occurred at our operating facilities prior to July 6, 2006, which represent the majority of our environmental accruals of $17.7 million as of March 31, 2026. This accrual represents our undiscounted estimate of costs reasonably expected to be incurred based on current laws and regulations, available facts, existing technologies, and our assessment of the likely remediation actions to be taken.

Based on approved and proposed remediation action plans for the various facilities, we expect that the implementation and ongoing monitoring could occur over a period of 30 or more years. As additional facts are developed, feasibility studies are completed, remediation plans are modified, necessary regulatory approvals for the implementation of remediation are obtained, alternative technologies are developed and/or other factors change, there may be revisions to management’s estimates, and actual costs may exceed the current environmental accruals by up to $14.2 million. Changes to our estimates may occur within the next 12 months as new information becomes available.

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

Other Contingencies. We are party to various lawsuits, claims, investigations and administrative proceedings that arise in connection with past and current operations. We evaluate such matters on a case-by-case basis and our policy is to vigorously contest any such claims we believe are without merit. We accrue for a legal liability when it is both probable that a liability has been incurred and the amount of the loss is reasonably estimable. Quarterly, in addition to when changes in facts and circumstances require it, we review and adjust these accruals to reflect the impacts of negotiations, settlements, rulings, advice of legal counsel and other information and events pertaining to a particular case. While uncertainties are inherent in the final outcome of such matters and it is presently impossible to determine the actual cost that may ultimately be incurred, we believe that we have sufficiently accrued for such matters and that the ultimate resolution of pending matters will not have a material impact on our consolidated financial position, operating results or liquidity.

7. Accumulated Other Comprehensive Income

The following table presents the changes in the accumulated balances for each component of AOCI (in millions of dollars):


	Quarter Ended March 31,
	2026			2025
Defined Benefit Plans:
Beginning balance	$	22.5		$	19.1
Actuarial loss arising during the period		—			(0.1	)
Amortization of net actuarial gain1		(0.6	)		(0.6	)
Amortization of prior service cost1		0.9			0.9
Less: income tax expense2		(0.1	)		(0.1	)
Other comprehensive income, net of tax		0.2			0.1
Ending balance	$	22.7		$	19.2

Cash Flow Hedges:
Beginning balance	$	4.3		$	1.4
Unrealized gain on cash flow hedges		15.8			8.7
Less: income tax expense		(3.7	)		(2.0	)
Net unrealized gain on cash flow hedges		12.1			6.7
Reclassification of unrealized gain upon settlement of cash flow hedges		(9.3	)		(5.5	)
Less: income tax benefit2		2.2			1.3
Net gain reclassified from AOCI to Net income		(7.1	)		(4.2	)
Other comprehensive income, net of tax		5.0			2.5
Ending balance3	$	9.3		$	3.9

Total AOCI ending balance	$	32.0		$	23.1

Amounts amortized out of AOCI related to pension and other postretirement and postemployment benefits were included within Net periodic postretirement and postemployment benefit cost (see Note 3).

Income tax amounts reclassified out of AOCI were included as a component of Income tax provision.

As of March 31, 2026, we estimate a net mark-to-market gain before tax of $13.0 million in AOCI will be reclassified into Net income upon settlement within the next 12 months.

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

8. Other Expense, Net

The following table presents the components of Other expense, net (in millions of dollars):


	Quarter Ended March 31,
	2026			2025
Interest income	$	0.2		$	0.2
Net periodic postretirement and postemployment benefit cost		(1.0	)		(1.2	)
Unrealized loss on equity securities		(0.2	)		(0.1	)
All other, net		—			(0.3	)
Other expense, net	$	(1.0	)	$	(1.4	)

Supply Chain Financing. We are party to several supply chain financing arrangements, in which we may sell certain of our customers’ trade accounts receivable to such customers’ financial institutions without recourse. During the quarter March 31, 2026 and March 31, 2025, we sold trade accounts receivable totaling $295.2 million and $270.0 million, respectively, related to these supply chain financing arrangements, of which our customers’ financial institutions applied discount fees totaling $6.5 million and $5.6 million, respectively. To the extent discount fees related to the sale of trade accounts receivable under supply chain financing arrangements are not reimbursed by our customers, they are included in Other expense, net. As of March 31, 2026, we had been and/or expected to be substantially reimbursed by our customers for these discount fees, in accordance with the underlying sales agreements.

9. Income Tax Matters

The following table presents the income tax provision by region (in millions of dollars):


	Quarter Ended March 31,
	2026			2025
Domestic	$	(19.3	)	$	(6.6	)
Foreign		(0.6	)		(0.6	)
Total	$	(19.9	)	$	(7.2	)

The income tax provision for the quarters ended March 31, 2026 and March 31, 2025 was $19.9 million and $7.2 million, respectively, reflecting an effective tax rate of 24% and 25%, respectively. There was no material difference between the effective tax rate and the blended statutory tax rate for the quarters ended March 31, 2026 and 2025.

Our gross unrecognized benefits relating to uncertain tax positions were $7.7 million and $7.4 million at March 31, 2026 and December 31, 2025, respectively. If recognized, these amounts would be reflected in our income tax provision and affect our effective tax rate.

10. Earnings Per Share

Basic net income per share is computed by dividing distributed and undistributed net income allocable to common shares by the weighted-average number of common shares outstanding during the applicable period. The basic weighted-average number of common shares outstanding during the period excludes non-vested share-based payment awards. Basic and diluted net income per share was calculated under the two-class method for the quarters ended March 31, 2026 and 2025.

Notes Index

KAISER ALUMINUM CORPORATION AND SUBSIDIARY COMPANIES

NOTES TO INTERIM CONSOLIDATED FINANCIAL STATEMENTS – UNAUDITED

The following table sets forth the computation of basic and diluted net income per share (in millions of dollars, except share and per share amounts):


	Quarter Ended March 31,
	2026		2025
Numerator:
Net income available to common shareholders1	$	62.5	$	21.6
Denominator – Weighted-average common shares outstanding (in thousands):
Basic		16,248		16,116
Add: dilutive effect of non-vested common shares, restricted stock units and performance shares2		596		283
Diluted		16,844		16,399

Net income per common share, Basic:	$	3.85	$	1.34
Net income per common share, Diluted:	$	3.71	$	1.31

Represents Net income less distributed and undistributed earnings allocated to non-vested restricted stock awards that contain non-forfeitable rights to dividends.

Quantities in the following discussion are denoted in whole shares. During the quarters ended March 31, 2026 and 2025, approximately 500 and 4,000 shares, respectively, were excluded from the weighted-average diluted shares computation as their inclusion would have been anti‑dilutive.

11. Supplemental Cash Flow Information


	Quarter Ended March 31,
	2026		2025
	(In millions of dollars)
Interest paid	$	9.6	$	10.0
Non-cash investing and financing activities (included in Accounts payable):
Unpaid purchases of property and equipment	$	14.4	$	22.1

Supplemental lease disclosures:
Operating lease liabilities arising from obtaining operating lease assets	$	3.1	$	—
Cash paid for amounts included in the measurement of operating lease liabilities	$	1.7	$	1.9
Finance lease liabilities arising from obtaining finance lease assets	$	2.6	$	0.3


	As of March 31,
	2026		2025
	(In millions of dollars)
Components of cash, cash equivalents and restricted cash:
Cash and cash equivalents	$	30.0	$	21.3
Restricted cash included in Other assets1		20.0		20.0
Total cash, cash equivalents and restricted cash presented on our Statements of Consolidated Cash Flows	$	50.0	$

KAISER ALUMINUM CORP 10-Q