Mechanics Bancorp Third Quarter Earnings Presentation October 30, 2025 Seattle, WA San Francisco, CA Los Angeles, CA 1

Disclaimer FORWARD-LOOKING STATEMENTS This presentation and statements made by representatives of Mechanics Bancorp (“Mechanics” or the “Company”) during the course of this presentation include “forward- looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause the Company’s actual results, performance or achievements to be materially different from any future results, performance or achievements anticipated in such statements. Forward-looking statements speak only as of the date they are made and, except as required by law, the Company does not assume any duty to update forward-looking statements. Such forward-looking statements include, but are not limited to, statements concerning such things as the Company’s outlook, business strategy, financial condition, efforts to make strategic acquisitions, integration activities and outlook, liquidity and sources of funding, market trends, operations and business, the impact of natural disasters or public health emergencies, information technology expenses, capital levels, mortgage servicing rights (“MSR”) assets, stock repurchases, dividend payments, projected losses on mortgage loans originated, total expenses, anticipated changes in our revenue, earnings, or taxes, the effects of government regulation applicable to our operations, the appropriateness of, and changes in, our allowance for credit losses and provision for (reversal of) credit losses, future benchmark rates and economic growth, anticipated investment yields, the collectability of loans, cybersecurity incidents, the outcome of litigation, and the Company’s other plans, objectives, strategies, expectations and intentions and other statements that are not statements of historical fact, and may be identified by words such as “anticipates,” “believes,” “building,” “continue,” “could,” “drive,” “estimates,” “expects,” “forecasts,” “goal,” “guidance,” “intends,” “may,” “might,” “outlook,” “plan,” “probable,” “projects,” “seeks,” “should,” “track,” “target,” “view” or “would” or the negative of these words and phrases or similar words or phrases. The following factors, among others, could cause actual results to differ from those set forth in the forward-looking statements: (i) the credit risks of lending activities, including the Company’s ability to estimate credit losses and increases to the allowance for credit losses, as well as the effects of changes in the level of, and trends in, loan delinquencies and write-offs; (ii) effectiveness of the Company’s data security controls in the face of cyberattacks and any legal, reputational and financial risks following a cybersecurity incident; (iii) changes in general economic, market and business conditions in areas or markets where the Company competes; (iv) changes in the interest rate environment; (v) risks associated with concentration in real estate related loans; (vi) the effects of the Company’s indebtedness on its ability to manage its business successfully, including the restrictions imposed by the indenture governing such indebtedness; (vii) disruptions to the economy and financial services industry, risks associated with uninsured deposits and responsive measures by federal or state governments or banking regulators, including increases in the cost of the Company’s deposit insurance assessments; (viii) cost and availability of capital; (ix) changes in state and federal laws, regulations or policies affecting one or more of the Company’s business segments, including changes in regulatory fees, capital requirements and the Dodd-Frank Wall Street Reform and Consumer Protection Act; (x) changes in key management; (xi) competition in the Company’s various lines of business from other banks and financial institutions, as well as investment banking and financial firms, asset-based non- bank lenders and government agencies; (xii) legal and regulatory proceedings; (xiii) risks associated with merger and acquisition integration; and (xiv) the Company’s ability to use excess capital in an effective manner. For further discussion of such factors, see the risk factors described in our current Report on Form 8-K filed on September 2, 2025, subsequent Quarterly Reports on Form 10-Q and other reports that we have filed with the Securities and Exchange Commission. All forward-looking statements are qualified in their entirety by this cautionary statement. The information contained herein is preliminary and based on Company data available at the time of the earnings presentation. It speaks only as of the particular date or dates included in the accompanying slides. Except as required by law, Mechanics does not undertake an obligation to, and disclaims any duty to, update any of the information herein. 2

Disclaimer (cont’d) Presentation of Results – HomeStreet Bank Merger On September 2, 2025, the merger of HomeStreet Bank, the wholly owned subsidiary of Mechanics Bancorp (formerly known as HomeStreet, Inc.) with and into Mechanics Bank, was completed. Mechanics Bank is the accounting acquirer (legal acquiree), HomeStreet Bank is the accounting acquiree and Mechanics Bancorp is the legal acquirer. Mechanic’s financial results for all periods ended prior to September 2, 2025 reflect Mechanics Bank’s historical financial results on a standalone basis. In addition, Mechanics’ reported financial results for the quarter and nine months ended September 30, 2025 reflect Mechanics Bank’s financial results on a standalone basis until the closing of the merger on September 2, 2025 and results of the combined company for September 2, 2025 through September 30, 2025. The number of shares issued and outstanding, earnings per share, and all references to share quantities or metrics of Mechanics have been retrospectively restated to reflect the equivalent number of shares issued in the merger since the merger was accounted for as a reverse acquisition. As the accounting acquirer, Mechanics Bank remeasured the identifiable assets acquired and liabilities assumed in the merger as of September 2, 2025 at their acquisition date fair values. 3

Mechanics Bancorp 3rd Quarter 2025 Financial Highlights 4 3rd Quarter Financial Highlights 9/30/2025 Summary Balance Sheet ▪ Mechanics Bancorp reported net income of $55.2mm in Q3’25 ▪ Fully diluted EPS of $0.25, BVPS of $12.54 and TBVPS of $7.731 ▪ ROAA of 1.18% and ROATCE of 14.2%1 ▪ $90.4mm bargain purchase gain from HomeStreet acquisition ▪ Significant one-time merger expenses in Q3, including: ▪ ~$27.8mm of compensation expenses, primarily due to CIC payments, severance and stock vesting ▪ ~$21.2mm core systems contract termination accrual ▪ ~$14.9mm of other one-time acquisition charges, primarily advisor fees and other professional services ▪ $47.0mm of total provision expense in Q3’25 due to one-time Non-PCD double count and increases to CECL factors ▪ ACL equal to 1.16% of total loans; 2.60x ACL / NPAs ▪ Total assets of $22.7bn, total gross loans of $14.6bn, total deposits of $19.5bn and tangible shareholder’s equity of $1.788bn1 ▪ All legacy HomeStreet wholesale funding paid off in September (no remaining brokered deposits or FHLB borrowings) ▪ 13.4% CET1 ratio and 75% loans-to-deposits ratio ▪ 8.23% Tangible common equity ratio1 at 9/30/2025 ▪ 1.53% cost of deposits in September ▪ 3.50% NIM in September (anticipate modest expansion moving forward as deposit costs decline and earning assets reprice) ▪ 360% CRE concentration ratio at 9/30/2025 1 Non-GAAP measure. Refer to section “Non-GAAP Financial Measures and Reconciliations” in the back of this presentation. Balance Sheet ($ in millions) Q3 '25 Q2 '25 vs Prior Qtr Cash and Cash Equivalents 1,443$ 2,079$ (636)$ Securities 4,904 3,954 951 FHLB Stock and Other Investments 149 103 45 Loans HFS 55 0 55 Commercial and Industrial 547 281 267 Multifamily 5,448 2,827 2,622 CRE Owner Occupied 709 323 386 CRE Non-owner Occupied 1,864 1,552 312 Construction and Land 536 135 401 Residential Real Estate 3,907 2,438 1,469 Auto 955 1,148 (193) Other Consumer 602 536 66 Loans HFI 14,569 9,240 5,329 Allowance for Loan Losses (169) (68) (101) Goodwill & Intangible Assets 987 877 110 MSRs 89 - 89 Other Assets 683 387 297 Total Assets 22,709$ 16,571$ 6,138$ Noninterest-bearing 6,748 5,454 1,295 Interest-bearing 1,733 1,332 401 Money Market 6,185 5,028 1,158 Savings 1,398 1,174 224 Time Deposits 3,387 981 2,406 Total Deposits 19,453 13,969 5,484 Senior Debt, Sub Debt, and TRUPs 190 0 190 Other Liabilities 292 186 106 Equity 2,774 2,417 358 Total Liabilities & Equity 22,709$ 16,571$ 6,138$

HomeStreet Merger Update Overview of Financials Highlights 5 Expected at Announcement 3Q25 / Updated ExpectationsMetric • Successful acquisition of HomeStreet, with transaction closing September 2, 2025 • Regulatory approval received promptly • Core systems conversion on track for March 2026 • On track to deliver initial costs savings estimate of ~$82mm, fully phased-in by the end of Q2’26; expect ~$450mm run-rate NIE for Mechanics • ($188mm) pre-tax interest rate mark on loans compared to ($200mm) expected at announcement • Profitability estimates for 2026 ($302mm)2 and 2027 ($325mm) remain unchanged from announcement • Strong first quarter of earnings as a public company due to a well-structured M&A deal • $90.4mm after-tax bargain purchase gain • Top decile deposits, clean balance sheet with strong ACL and robust capital levels positions Mechanics to be the leading West Coast community bank Capital Ratios CET1 12.4% 13.4% TCE / TA1 8.0% 8.2% CRE Concentration 390% 360% ✓ ✓ ✓ Source: FactSet, S&P Global Market Intelligence; Note: Financial data as of September 30, 2025; Market data as of October 21, 2025. 1 Non-GAAP measure. Refer to section “Non-GAAP Financial Measures and Reconciliations” in the back of this presentation. 2 Fully synergized and excluding one-time merger integration costs. Wholesale Funding 0% 0% Noninterest-Bearing Deposits / Deposits 35% 35% Loans / Deposits 78% 75% Balance Sheet ✓ 2026E ROATCE2 18% 18% 2026E Net Income2 $302mm $302mm 2026E ROAA2 1.4% 1.4% 2026 Profitability ✓ ✓ ✓ ✓ ✓

Key Stats2 vs. KRX3 Regional Banking Index Mechanics Bancorp Overview Source: S&P Global Market Intelligence; Note: Financial data as of September 30, 2025, unless otherwise specified; 1 Includes banks headquartered in California with less than $250bn in total assets. 2 2026E ROATCE and ROAA fully synergized and excluding one-time merger integration costs for Mechanics Bank. 3 Represents the Nasdaq Regional Banking Index. CoD: 1.45% KRX: 1.98% #10 of 51 NIB: 35% KRX: 25% #3 of 51 L/D: 75% KRX: 87% #11 of 51 ROATCE: 18.0% KRX: 14.1% #5 of 51 As of MRQ: CET1: 13.4% KRX: 12.0% #14 of 51 ROAA: 1.40% KRX: 1.18% #11 of 51 $22.7bn Total assets 166 Branches #3 CA market share by deposits1 Mechanics Bancorp Overview 18% 37% 27% 4% 7% $14.6bn CRE C&I 1-4 Family Cons. / Other Auto 35% 41% 7% 17% $19.5bn Noninterest- bearing Interest-bearing transaction Savings Time Loans Multifamily C&D Deposits 4% 4% 6 In runoff As of MRQ: San Francisco Oakland 880 680 680 90 5 5 Santa Barbara Bakersfield CA OR WA 8 10 40 15 5 5 90 82 182 84 105 405 210 Palm Springs San Diego Los Angeles Santa Maria Santa Barbara Bakersfield Fresno Salinas San Francisco Sacramento Yuba City Chico Redding Seattle Bremerton Seattle Everett Bremerton Tacoma Olympia Vancouver Portland 705 H-3 Lihue Honolulu Hilo Lihue Wailuku H-1 Kailua-Kona Wahiawa H-2 Honolulu Legend Mechanics (166) HI As of MRQ: As of MRQ: 2026E: 2026E:

Strong Profitability and Capital vs. West Coast Peers¹ 2026E ROATCE2 ~1.4% 1.34% 1.21% 1.17% 1.17% 1.04% 1.00% 0.92% 0.89% 0.87% 0.84% 0.73% 2026E CVBF GBCI BANR TCBK FHB FIBK HTBK HFWA WAFD BOH BANC 2026E ROAA2 Source: FactSet, S&P Global Market Intelligence; Note: Financial data as of most recent quarter available; Market data as of October 21, 2025; ¹ West coast peer banks include BANC, BANR, BOH, CVBF, FHB, FIBK, GBCI, HFWA, HTBK, TCBK and WAFD. 2 Fully synergized and excluding one-time merger integration costs for Mechanics Bank. 7 ~18% 14.7% 14.1% 13.7% 13.4% 13.1% 12.4% 11.7% 11.6% 10.4% 10.1% 10.0% 2026E GBCI FHB CVBF BOH HFWA BANR TCBK FIBK WAFD BANC HTBK 16.3% 13.4% 13.4% 13.4% 13.2% 13.0% 12.8% 12.6% 12.4% 11.8% 11.8% 10.1% CVBF MCHB FIBK TCBK HTBK FHB BANR GBCI HFWA BOH WAFD BANC MRQ CET1 Ratio

4th Largest West Coast and 3rd Largest California Bank by Deposits Top West Coast Headquartered Banks by Deposits Top California Headquartered Banks by Deposits Significant Scarcity Value in Highly Desirable West Coast and California Markets $47.7 $21.8 $15.4 $14.8 $12.0 $9.9 $8.7 $8.4 $5.7 $5.5 $53.7 $50.0 $21.8 $19.1 $15.7 $15.5 $12.9 $12.0 $10.5 $8.7 Includes banks headquartered in California, Oregon and Washington with less than $250bn total assets; California, Oregon and Washington deposits shown Includes banks headquartered in California with less than $250bn total assets; California deposits shown 8Source: S&P Global Market Intelligence; Note: Deposit data as of June 30, 2025.

Top 10 Deposit Share in Many Attractive West Coast Markets Top West Coast MSAs Seattle San Francisco Los Angeles San Luis Obispo Santa Barbara Salinas Ventura Riverside El Centro Siskiyou County $3.8 | #10 $1.1 | #6 $3.2 | #9 $2.1 | #29 $1.5 | #2 $1.0 | #4 $0.8 | #17 $0.6 | #7 $0.4 | #1 $0.8 | #6 Top 10 10–20 >20 California and Washington Are Especially Attractive Markets Deposits ($bn) | Rank California is the 2nd largest deposit market in the U.S. California and Washington are in top 10 states for household income¹: WA (#5): $96,000 CA (#9): $95,000 California and Washington are central hubs for leading technology, media and healthcare companies California and Washington are home to many exceptional universities and academic institutions California has the 5th largest economy in the world by GDP Seattle is one of the fastest growing large cities in the United States 9 Honolulu $0.6 | #1 Sacramento $0.4 | #18 Chico $0.4 | #9Bakersfield $0.3 | #8 Merced $0.3 | #5 Source: Public Policy Institute of California; S&P Global Market Intelligence; Note: Branch and deposit data as of June 30, 2025; ¹ Represents current median household income; excludes District of Columbia.