Westermann Donald Michael 4

4 · Eastern Bankshares, Inc. · Filed Mar 3, 2026

Insider Transaction Report

Form 4

Period: 2026-03-01

Eastern Bankshares, Inc.EBC

Westermann Donald Michael

Chief Information Officer

Transactions

Exercise/Conversion
Common Stock
[F1]
2026-03-01+14,359→ 35,219 total
Tax Payment
Common Stock
2026-03-01$19.56/sh−6,522$127,570→ 28,697 total
Award
Common Stock
[F9]
2026-03-01+5,520→ 34,217 total
Tax Payment
Common Stock
2026-03-01$19.56/sh−2,449$47,902→ 31,768 total
Exercise/Conversion
Restricted Stock Units
[F1][F4]
2026-03-01−9,488→ 9,488 total
→ Common stock (9,488 underlying)
Exercise/Conversion
Restricted Stock Units
[F1][F5]
2026-03-01−1,977→ 0 total
→ Common stock (1,977 underlying)
Exercise/Conversion
Restricted Stock Units
[F1][F6]
2026-03-01−2,894→ 2,895 total
→ Common stock (2,894 underlying)
Award
Restricted Stock Units
[F3][F8]
2026-03-02+7,099→ 7,099 total
→ Common stock (7,099 underlying)

Holdings

Common Stock
[F2]
(indirect: By 401(k))
22,682
Common Stock
[F2]
(indirect: By ESOP)
4,921
Restricted Stock Units
[F1][F7]
→ Common stock (34,697 underlying)
34,697

Footnotes (9)

[F1]Restricted stock units convert into common stock on a one-for-one basis.
[F2]Reflects the amount of shares beneficially owned, including shares received due to automatic dividend reinvestment, as of the date of this report.
[F3]Each restricted stock unit represents a contingent right to receive one share of EBC common stock on the applicable vesting date.
[F4]On March 1, 2022, the reporting person was granted 47,438 restricted stock units that vest in five equal annual installments beginning March 1, 2023, subject to continued service. Vested shares will be issued to the reporting person as soon as practicable after the vesting date.
[F5]On March 1, 2023, the reporting person was granted 5,930 restricted stock units that vest in three equal annual installments beginning March 1, 2024, subject to continued service. Vested shares will be issued to the reporting person as soon as practicable after the vesting date.
[F6]On March 1, 2024, the reporting person was granted 8,683 restricted stock units that vest in three equal annual installments beginning March 1, 2025, subject to continued service. Vested shares will be issued to the reporting person as soon as practicable after the vesting date.
[F7]On March 3, 2025, the reporting person was granted 34,697 restricted stock units of which 6,497 vest in three equal annual installments beginning March 3, 2026 and 28,200 vest after 3 years, subject to continued service. Vested shares will be issued to the reporting person as soon as practicable after the vesting date.
[F8]On March 2, 2026, the reporting person was granted 7,099 restricted stock units that vest in three equal annual installments beginning March 2, 2027, subject to continued service. Vested shares will be issued to the reporting person as soon as practicable after the vesting date.
[F9]Represents shares of Eastern Bankshares, Inc. (the "Company") common stock, par value $0.01 per share ("Common Stock") received upon vesting of a performance restricted stock unit ("PRSU") award eligible to vest based upon the Company's performance on total shareholder return ("TSR") measured at the end of the three-year performance period of January 1, 2023 through December 31, 2025 (the "Performance Period") relative to TSR performance over that performance period of the banks listed on the KBW Nasdaq Regional Banking Index (the "TSR Measure"). The Compensation and Human Capital Management Committee determined that the Company's performance of the TSR Measure resulted in a payout of 93.1% of target.

Signature

/s/ Kathleen R. Henry, by Power of Attorney|2026-03-03

Documents

1 file

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ownership.xmlPrimary
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