Form 8-K

8-K — Columbia Financial, Inc./MD/

Accession: 0002115119-26-000032

Filed: 2026-10-29

Period: 2026-10-29

CIK: 0002115119

SIC: 6035 (SAVINGS INSTITUTION, FEDERALLY CHARTERED)

Item: Results of Operations and Financial Condition

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — clbk-20261029.htm (Primary)

EX-99.1 (exhibit9913q20269302026.htm)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: clbk-20261029.htm · Sequence: 1

clbk-20261029

false000211511900021151192020-07-292020-07-29

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF

THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of Earliest Event Reported): October 29, 2026

Columbia Financial, Inc.

(Exact Name of Registrant as Specified in its Charter)

Maryland 001-43410 42-1991301

(State or other jurisdiction (Commission (IRS Employer

of incorporation) File Number) Identification Number)

19-01 Route 208 North, Fair Lawn, New Jersey 07410

(Address of principal executive offices)

(800) 522-4167

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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, $0.01 par value per share CLBK The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

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. ☐

Item 2.02 Results of Operations and Financial Condition

On October 29, 2026, Columbia Financial, Inc. (the "Company") issued a press release announcing its financial results for the three and nine months ended September 30, 2026. The Company's press release is included as Exhibit 99.1 to this report.

The information set forth in this Item 2.02 and in the attached Exhibit 99.1 is deemed to be “furnished” and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section.

Item 8.01 Other Events

On October 29, 2026, the Company announced that its Board of Directors has declared a quarterly cash dividend of $0.05 per share, payable on November 25, 2026, to shareholders of record as of November 10, 2026.

Item 9.01 Financial Statements and Exhibits

(d) Exhibits

Exhibit Number Description

99.1

Press release dated October 29, 2026

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunder duly authorized.

Date: October 29, 2026 /s/Thomas F. Splaine Jr.

Thomas F. Splaine Jr.

Executive Vice President and Chief Financial Officer

EX-99.1

Filename: exhibit9913q20269302026.htm · Sequence: 2

Document

Columbia Financial, Inc. Announces

Q3 2026 Financial Results

and

Quarterly Cash Dividend

Fair Lawn, New Jersey (October 29, 2026): Columbia Financial, Inc. (the “Company”) (NASDAQ: CLBK), the holding company for Columbia Bank ("Columbia"), reported net income of $5.2 million, or $0.02 per basic and diluted share, for the quarter ended September 30, 2026, as compared to $14.9 million, or $0.07 per basic and diluted share, for the quarter ended September 30, 2025. For the nine months ended September 30, 2026, the Company reported net income of $32.8 million, or $0.14 per basic and diluted share, as compared to $36.1 million, or $0.16 per basic and diluted share, for the nine months ended September 30, 2025.

For the quarter ended September 30, 2026, the Company reported core net income (a non-GAAP financial measure) of $40.6 million, or $0.16 per basic and diluted share, as compared to $15.4 million, or $0.07 per basic and diluted share for the quarter ended September 30, 2025. For the nine months ended September 30, 2026, the Company reported core net income of $70.6 million, or $0.30 per basic and diluted share, as compared to $37.1 million, or $0.17 per basic and diluted share for the nine months ended September 30, 2025. See the "Reconciliation of GAAP to Non-GAAP Financial Measures" included in this release, detailing non-core items, related core net income, per share amounts and select performance ratios.

Mr. Thomas J. Kemly, President and Chief Executive Officer commented: “During the quarter, our team successfully completed the second-step conversion offering and simultaneous acquisition of Northfield Bancorp, Inc. (“Northfield”), and executed a series of transactions to improve earnings, reduce interest rate and credit risk on the balance sheet by selling securities and delinquent, nonperforming and criticized and classified assets, as well as, materially reducing our exposure to New York City rent regulated multifamily loans.”

Mr. Kemly noted, “In addition, we continue to attract experienced commercial bankers and other professionals to grow our Company and deliver premier lending, deposit and treasury solutions to deploy our capital and to capture current market share in the markets we serve. We continue to believe that our approach to community relationship banking, and our disciplined focus on capital deployment will drive strong earnings growth and stockholder returns."

Financial Highlights

•Total assets increased $5.4 billion to $17.6 billion at September 30, 2026 from $12.2 billion at June 30, 2026, primarily due to the acquisition of Northfield, and the second-step conversion stock offering.

•Return on average assets for the quarter ended September 30, 2026 decreased to 0.13% as compared to 0.55% for the quarter ended September 30, 2025, while core return on average assets for the quarter ended September 30, 2026 increased to 0.97% as compared to 0.56% for the quarter ended September 30, 2025.

•Net interest margin of 2.96% for the quarter ended September 30, 2026 increased by 67 basis points compared to 2.29% for the quarter ended September 30, 2025, and increased 52 basis points compared to 2.44% for the quarter ended June 30, 2026.

•Total gross loans increased $3.1 billion, or 37.2%, for September 30, 2026, as compared to June 30, 2026, due primarily to $3.2 billion in loans acquired in the Northfield acquisition. Commercial real estate, construction and commercial business loans, gross, increased $899.8 million, or 23.0% for September 30, 2026, as compared to June 30, 2026, primarily due to the Northfield acquisition.

•Total deposits increased $3.1 billion, or 32.2%, for September 30, 2026, as compared to June 30, 2026, mainly due to $3.8 billion in deposits acquired in the Northfield acquisition, partially offset by $970.1 million in stock subscription proceeds that were transferred to stockholders' equity. Non-interest-bearing deposits increased $771.6 million, or 49.6%, as compared to June 30, 2026, mainly due to $747.9 million in deposits acquired in the Northfield acquisition.

•The Company's Board of Directors declared a quarterly cash dividend of $0.05 per share to be paid on November 25, 2026, to stockholders of record as of November 10, 2026.

Significant Transactions Impacting the Three Months Ended September 30, 2026

The Company's growth, financial condition and earnings for the quarter ended September 30, 2026 were materially impacted by a series of transactions including:

•Completion of its second-step conversion stock offering and raising approximately $1.6 billion of common stockholders' equity net of underwriting and transactional expenses. Total shares outstanding following completion of the stock offering and Northfield acquisition were 269,539,984.

•The acquisition of Northfield on July 20, 2026, added approximately $5.2 billion in total assets, $3.2 billion in loans receivable and $202.3 million in loans held-for-sale, $1.2 billion in securities, $646.4 million in borrowings, and $3.8 billion in deposits, inclusive of purchase accounting adjustments. The Company recorded a bargain purchase gain of $25.7 million, net of tax, and a core deposit intangible $76.2 million during the quarter ended September 30, 2026. Merger-related expenses recognized for the quarter ended September 30, 2026 were $30.6 million. The Company currently plans to complete the core system conversion during the first quarter of 2027.

•Purchase of $1.1 billion of debt securities designated as both available for sale and held to maturity, with a weighted average yield of 4.80% and a duration of approximately 2.0 years. Approximately one-third of these debt securities purchased have coupons that adjust monthly. Furthermore, the Company repaid and prepaid $353.5 million of borrowings with a weighted average cost of 3.97%.

•The sale of $650.6 million of Northfield debt securities available for sale resulting in no gain or loss, as the securities were marked-to-market as part of purchase accounting adjustments. The proceeds from the sales were reinvested in debt securities with a similar yield, but with improved cash flow stability in various rate scenarios.

•The sale of $254.7 million of debt securities available for sale at a net loss of $40.8 million. With the proceeds, the Company purchased $221.2 million of debt securities. The yield on the securities purchased was 445 basis points higher than the securities sold, with lower average lives and duration, and the Company currently expects to earn approximately $9.3 million in additional interest income over the next twelve months as a result of this transaction.

•Sold $55.6 million of commercial real estate and multifamily loans originated by Northfield that would be criticized or classified assets under the Company’s risk rating system. This transaction resulted in a loss on sale of loans of $1.1 million for the quarter ended September 30, 2026.

•Entered into a letter of intent to sell loans of $246.2 million of unpaid principal, collateralized by New York City rent regulated multifamily properties originated by Northfield. The loans selected for sale were deemed to have the highest credit risk based upon the percentage of units that were rent regulated, the estimated loan to value or the debt service coverage. This transaction resulted in a loss on loans of $5.9 million for the quarter ended September 30, 2026. The sale closed on October 27, 2026. The Company’s remaining exposure to New York City rent regulated multifamily loans was $164.6 million, or less than 1.0% of total assets at October 27, 2026.

•Entered into a letter of intent to sell $9.1 million of delinquent and nonperforming residential real estate loans originated by Columbia Bank. The Company recorded a loss of approximately $900,000 related to the transaction. This sale closed in October 2026.

Results of Operations for the Three Months Ended September 30, 2026 and September 30, 2025

Net income of $5.2 million was recorded for the quarter ended September 30, 2026, a decrease of $9.6 million compared to net income of $14.9 million for the quarter ended September 30, 2025. The decrease in net income was primarily attributable to a $23.8 million decrease in non-interest income and a $52.4 million increase in non-interest expense, partially offset by a $57.0 million increase in net interest income, a $512,000 decrease in provision for credit losses and a $9.1 million decrease in income tax expense.

Net interest income was $114.4 million for the quarter ended September 30, 2026, an increase of $57.0 million, or 99.3%, from $57.4 million for the quarter ended September 30, 2025. The increase in net interest income was primarily attributable to a $72.2 million increase in interest income partially offset by a $15.2 million increase in interest expense on deposits and borrowings. The increase in interest income was primarily due to an increase in the average balance of total interest-earning assets coupled with an increase in average yields on loans, while the increase in interest expense was primarily due to an increase in the average balance of both deposits and borrowings. Accretion of loan yield adjustments for the quarter ended September 30, 2026 totaled $6.8 million. Prepayment penalties, which are included in interest income on loans, totaled $771,000 for the quarter ended September 30, 2026, compared to $767,000 for the quarter ended September 30, 2025.

The average yield on loans for the quarter ended September 30, 2026 increased 33 basis points to 5.37%, as compared to 5.04% for the quarter ended September 30, 2025. Interest income on loans increased due to an increase in both the average balance and yield on loans mainly related to the Northfield acquisition. The average yield on securities for the quarter ended September 30, 2026 increased 55 basis points to 3.96%, as compared to 3.41% for the quarter ended September 30, 2025. The average yield on other interest-earning assets for the quarter ended September 30, 2026 decreased 137 basis points to 3.87%, as compared to 5.24% for the quarter ended September 30, 2025, mainly due to an increase in the average balance of other interest-earning assets invested in lower earning interest-bearing cash accounts, coupled with a 91 basis point decrease in the dividend rate received on Federal Home Loan Bank stock.

Total interest expense was $78.3 million for the quarter ended September 30, 2026, an increase of $15.2 million, or 24.2%, from $63.0 million for the quarter ended September 30, 2025. The increase in interest expense was primarily attributable to increases in the average balance of interest-bearing deposits and borrowings partially offset by a 31 basis point decrease in the average cost of interest-bearing deposits coupled with a 17 basis point decrease in the average cost of borrowings. Interest expense on deposits increased $13.3 million, or 26.8%, primarily due to the increase in the average balances as a result of the Northfield acquisition during the quarter ended September 30, 2026. Interest expense on borrowings increased $2.0 million, or 14.7%, for the quarter ended September 30, 2026 as compared to the quarter ended September 30, 2025 due to an increase in the average balance of borrowings, partially offset by a decrease in the average cost of borrowings.

The Company's net interest margin for the quarter ended September 30, 2026 increased 67 basis points to 2.96% when compared to 2.29%, for the quarter ended September 30, 2025, predominately due to a decrease in the average cost of interest-bearing liabilities. The weighted average yield on interest-earning assets increased 18 basis point to 4.99% for the quarter ended September 30, 2026 as compared to 4.81% for the quarter ended September 30, 2025. The average cost of interest-bearing liabilities decreased 33 basis points to 2.81% for the quarter ended September 30, 2026 as compared to 3.14% for the quarter ended September 30, 2025.

The provision for credit losses on loans for the quarter ended September 30, 2026 was $1.8 million, a decrease of $512,000, or 21.8%, from $2.3 million for the quarter ended September 30, 2025. The decrease in the provision for credit losses was primarily attributable to lower net charge-offs, partially offset by an increase in loan balances.

Non-interest (loss) income was $(13.9) million for the quarter ended September 30, 2026, a decrease of $23.8 million, or 241.0%, from $9.9 million for the quarter ended September 30, 2025, mainly due to a $40.8 million increase in the loss on securities transactions coupled with a $7.6 million loss on transfer of loans to held-for-sale as previously discussed. These decreases were partially offset by a bargain purchase gain of $25.7 million, net of tax, related to the Northfield acquisition.

Non-interest expense was $97.5 million for the quarter ended September 30, 2026, an increase of $52.4 million, or 116.3%, from $45.1 million for the quarter ended September 30, 2025. The increase was primarily attributable to an increase in compensation and employee benefits expense of $14.2 million, an increase in occupancy expense of $2.6 million, an increase in merger-related expenses of $30.6 million, and an increase in amortization of intangible assets of $2.9 million due to the Northfield acquisition. The increase in compensation and employee benefits expense was due to an increase in the number of employees and related employee benefits due to the Northfield acquisition and annual merit increases. The increase in occupancy expense was due to the costs related to the Northfield acquisition.

An income tax benefit of $4.1 million was recorded for the quarter ended September 30, 2026, a decrease of $9.1 million, as compared to income tax expense of $5.0 million for the quarter ended September 30, 2025, mainly due to lower pre-tax income

partially offset by non-deductible merger-related expenses. The Company's effective tax rate was 16.7% and 25.0% for the quarters ended September 30, 2026 and 2025, respectively.

Results of Operations for the Nine Months Ended September 30, 2026 and September 30, 2025

Net income of $32.8 million was recorded for the nine months ended September 30, 2026, a decrease of $3.3 million, or 9.0%, compared to net income of $36.1 million for the nine months ended September 30, 2025. The decrease in net income was primarily attributable to a $24.8 million decrease in non-interest income, and a $60.6 million increase in non-interest expense partially offset by a $76.3 million increase in net interest income, a $645,000 decrease in provision for credit losses, and a $5.2 million decrease in income tax expense.

Net interest income was $237.7 million for the nine months ended September 30, 2026, an increase of $76.3 million, or 47.3%, from $161.4 million for the nine months ended September 30, 2025. The increase in net interest income was primarily attributable to a $84.7 million increase in interest income partially offset by a $8.4 million increase in interest expense on deposits and borrowings. The increase in interest income was primarily due to an increase in the average balance of loans coupled with an increase in the average yield on loans. Accretion of loan yield adjustments for the nine months ended September 30, 2026 totaled $6.8 million, mainly related to the Northfield acquisition. Prepayment penalties, which are included in interest income on loans, totaled $1.5 million for the nine months ended September 30, 2026, compared to $1.6 million for the nine months ended September 30, 2025.

The average yield on loans for the nine months ended September 30, 2026 increased 20 basis points to 5.16%, as compared to 4.96% for the nine months ended September 30, 2025. Interest income on loans increased due to an increase in both the average balance and yield on loans. The average yield on securities for the nine months ended September 30, 2026 increased 23 basis points to 3.70%, as compared to 3.47% for the nine months ended September 30, 2025. The average yield on other interest-earning assets for the nine months ended September 30, 2026 decreased 126 basis points to 4.13%, as compared to 5.39% for the nine months ended September 30, 2025, mainly due to an increase in the average balance of other interest-earning assets invested in lower earning interest-bearing cash accounts, coupled with a lower dividend rate received on Federal Home Loan Bank stock.

Total interest expense was $196.1 million for the nine months ended September 30, 2026, an increase of $8.4 million, or 4.5%, from $187.7 million for the nine months ended September 30, 2025. The increase in interest expense was primarily attributable to an increase in the average balances of interest-bearing deposits and borrowings, partially offset by a 30 basis point decrease in the average cost of interest-bearing deposits coupled with a 27 basis point decrease in the average cost of borrowings mainly related to the Northfield acquisition. Interest expense on deposits increased $6.2 million, or 4.2%, for the nine months ended September 30, 2026 as compared to the nine months ended September 30, 2025, due to an increase in the average balance of deposits, while interest expense on borrowings increased $2.2 million, or 5.7%, for the nine months ended September 30, 2026 as compared to the nine months ended September 30, 2025, due to the increase in the average balance of borrowings.

The Company's net interest margin for the nine months ended September 30, 2026 increased 46 basis points to 2.66% when compared to 2.20% for the nine months ended September 30, 2025, due to an increase in the average yield on interest-earning assets coupled with a decrease in the average cost of interest-bearing liabilities. The weighted average yield on interest-earning assets increased 10 basis points to 4.85% for the nine months ended September 30, 2026 as compared to 4.75% for the nine months ended September 30, 2025. The average cost of interest-bearing liabilities decreased 30 basis points to 2.87% for the nine months ended September 30, 2026 as compared to 3.17% for the nine months ended September 30, 2025.

The provision for credit losses for the nine months ended September 30, 2026 was $7.1 million, a decrease of $645,000, or 8.3% from $7.7 million for the nine months ended September 30, 2025. The decrease in the provision for credit losses was primarily attributable to a decrease in net charge-offs, which totaled $2.9 million for the nine months ended September 30, 2026 as compared to $5.2 million for the nine months ended September 30, 2025, partially offset by an increase in loan balances.

Non-interest income was $3.7 million for the nine months ended September 30, 2026, a decrease of $24.8 million, or 87.1%, from $28.5 million for the nine months ended September 30, 2025. The decrease was primarily attributable to a $40.8 million increase in the loss on securities transactions, coupled with a $7.7 million increase in the loss on transfer of loans. These decreases were partially offset by a bargain purchase gain of $25.7 million, net of tax, resulting from the Northfield acquisition,

a $2.7 million increase in bank-owned life insurance due to income from the acquisition of such policies in the Northfield acquisition, death benefit claims in the 2026 period, and income related to the transition and exchange into higher yielding bank-owned life insurance policies.

Non-interest expense was $194.4 million for the nine months ended September 30, 2026, an increase of $60.6 million, or 45.3%, from $133.8 million for the nine months ended September 30, 2025. The increase was primarily attributable to an increase in compensation and employee benefits expense of $19.8 million, an increase in occupancy expense of $4.0 million, an increase in data processing and software expenses of $2.7 million and an increase in merger-related expenses of $33.3 million, partially offset by a decrease of $2.6 million in professional fees. The increase in compensation and employee benefits expense was due to an increase in the number of employees and related employee benefits due to the Northfield acquisition and annual merit increases. The increase in occupancy expense was due to the costs related to the Northfield branches acquired.

Income tax expense was $7.0 million for the nine months ended September 30, 2026, a decrease of $5.2 million, as compared to income tax expense of $12.3 million for the nine months ended September 30, 2025, mainly due to a decrease in pre-tax income. The Company's effective tax rate was 49.7% and 25.4% for the nine months ended September 30, 2026 and 2025, respectively. The increase in the 2026 effective tax rate was due primarily to non-deductible merger-related expenses.

Balance Sheet Summary

Total assets increased $6.5 billion, or 59.4%, to $17.6 billion at September 30, 2026 from $11.0 billion at December 31, 2025. The increase in total assets was primarily attributable to increases in cash and cash equivalents of $118.0 million, debt securities available for sale of $1.7 billion, debt securities held to maturity of $516.0 million, loans held-for-sale of $211.4 million, loans receivable, net, of $3.4 billion, bank-owned life insurance of $191.8 million and other assets of $157.6 million, mainly due to assets acquired in the Northfield merger.

Cash and cash equivalents increased $118.0 million, or 34.6%, to $458.8 million at September 30, 2026 from $340.8 million at December 31, 2025. The increase was primarily attributable to proceeds raised through the offering and cash and cash equivalents of $95.2 million acquired in the Northfield acquisition.

Debt securities available for sale increased $1.7 billion, or 151.0%, to $2.8 billion at September 30, 2026 from $1.1 billion at December 31, 2025. The increase was primarily attributable to $1.2 billion of securities acquired in the Northfield acquisition, and purchases of $1.7 billion of securities, consisting primarily of U.S. government obligations and mortgage-backed securities which were purchased with proceeds from the second-step conversion offering. These increases were partially offset by sales of securities with an amortized cost of $643.3 million which were acquired in the Northfield acquisition and the sale of an additional $213.9 million of seasoned securities sold as part of a balance sheet repositioning transaction, which resulted in a realized loss of $40.8 million for the quarter ended September 30, 2026. The Company sold predominantly fixed rate, low-yielding debt securities and used the proceeds to repay high costing borrowings acquired from Northfield and purchase higher-yielding debt securities to improve the net interest rate margin in the future. The increase in debt securities available for sale also included a decrease of $33.9 million in the unrealized loss on securities available for sale.

Debt securities held to maturity increased $516.0 million, or 130.2%, to $912.2 million at September 30, 2026 from $396.2 million at December 31, 2025. The increase was attributable to purchases of securities of $542.8 million, consisting primarily of U.S. government obligations and mortgage-backed securities, partially offset by maturities on securities of $14.9 million, and repayments on securities of $13.1 million.

Loans held-for-sale increased to $211.4 million, at September 30, 2026 from zero at December 31, 2025. A portion of the loans held-for-sale acquired in the Northfield acquisition along with $9.1 million of residential real estate loans originated by Columbia Bank were transferred to loans held-for-sale at fair value and were subsequently sold in October 2026.

Loans receivable, net, increased $3.4 billion, or 41.9%, to $11.7 billion at September 30, 2026 from $8.2 billion at December 31, 2025, primarily due to $3.2 billion of loans acquired in the Northfield acquisition excluding loans held-for sale. One-to-four family real estate loans, multifamily loans, commercial real estate loans, construction loans, commercial business

loans and home equity loans and advances increased $84.0 million, $2.0 billion, $774.9 million, $33.1 million, $253.3 million, and $193.8 million, respectively. The allowance for credit losses for loans increased $51.4 million to $118.6 million at September 30, 2026 from $67.2 million at December 31, 2025, primarily due to the Northfield acquisition and organic loan growth during the nine months ended September 30, 2026. As part of the merger with Northfield, the Company acquired $3.5 billion in loans, net of purchase accounting adjustments related to interest rates. The allowance for credit losses increased due to the day 1 Northfield CECL adjustment of $47.1 million recorded as part of the Northfield acquisition.

Bank-owned life insurance increased $191.8 million, or 67.7%, to $474.9 million at September 30, 2026 from $283.1 million at December 31, 2025, as the Company acquired $187.1 million of bank-owned life insurance policies in the Northfield acquisition, and $8.7 million of income was recognized from bank-owned life insurance for the nine months ended September 30, 2026.

Other assets increased $157.6 million, or 47.0%, to $493.3 million at September 30, 2026 from $335.7 million at December 31, 2025 primarily due to $134.2 million in other assets acquired as part of the Northfield acquisition, an increase in net pension assets of $27.0 million, and an increase of $16.6 million in swap contracts.

Total liabilities increased $4.5 billion, or 46.0%, to $14.4 billion at September 30, 2026 from $9.9 billion at December 31, 2025. The increase was primarily attributable to an increase in total deposits of $4.1 billion, primarily due to the addition of Northfield deposits, an increase in borrowings of $312.8 million, and an increase in accrued expenses and other liabilities of $87.4 million. The increase in total deposits consisted of increases in non-interest-bearing demand deposits, interest-bearing demand deposits, money market accounts, savings and club accounts, and certificates of deposits of $810.1 million, $1.4 billion, $254.3 million, $767.6 million and $868.5 million respectively. The increase in each category of deposits largely reflected the impact of deposits acquired from Northfield while also reflecting an increase related to the impact of continuing business development and competitive pricing strategies. The increase in accrued expenses and other liabilities included $67.0 million acquired from Northfield, which primarily consisted of lease liabilities, accrued expenses and benefit plan related liabilities, and an increase in collateral pledged for interest rate swaps. The $312.8 million increase in borrowings was driven by borrowings acquired from Northfield which included a net increase in short-term borrowings of $175.0 million, coupled with new long-term borrowings of $161.8 million, and long-term subordinated debentures assumed from Northfield totaling $62.0 million, partially offset by repayments of $82.0 million in maturing long-term borrowings. Included in these borrowings were $646.4 million in borrowings assumed in the Northfield acquisition, of which $195.6 were subsequently prepaid, resulting in a $196,000 loss on extinguishment of debt.

Total stockholders’ equity increased $2.0 billion, or 172.7%, with a balance of $3.2 billion at September 30, 2026 from $1.2 billion and December 31, 2025. The increase in stockholders' equity reflected $1.6 billion in capital stock issued in the Company's second-step conversion coupled with $404.3 million in capital stock issued in conjunction with the acquisition of Northfield. The increase also included net income of $32.8 million, partially offset by dividends declared and paid of $12.9 million.

Asset Quality

The Company's non-performing loans at September 30, 2026 excluding purchased credit deteriorated ("PCD") loans, totaled $36.5 million, or 0.31% of total gross loans, as compared to $38.0 million, or 0.46% of total gross loans, at December 31, 2025. The $1.5 million decrease in non-performing loans was primarily attributable to a decrease in non-performing one-to-four family loans of $5.4 million. This decrease was mainly due to the transfer of $4.9 million of non-performing one-to-four family loans to loans held-for-sale in September 2026, which were sold in October 2026, a decrease in non-performing commercial business loans of $2.8 million, and a decrease in non-performing construction loans of $4.1 million. The decrease in non-performing construction loans was due to one loan of $5.9 million being transferred to other real estate owned in March 2026 and subsequently sold in September 2026. These decreases were partially offset by an increase of $11.6 million in commercial real estate loans, which included a $10.6 million loan on a six-story mixed use building, located in Philadelphia, Pennsylvania, which contains apartments and commercial/storage space designated as non-performing during the 2026 period. Non-

performing assets as a percentage of total assets totaled 0.21% at September 30, 2026, as compared to 0.34% at December 31, 2025.

For the quarter ended September 30, 2026, net charge-offs totaled $1.5 million, as compared to net charge-offs of $1.2 million for the quarter ended September 30, 2025. For the nine months ended September 30, 2026, net charge-offs totaled $2.9 million, as compared to net charge-offs of $5.2 million for the nine months ended September 30, 2025. Charge-offs for the nine months ended September 30, 2025 included $3.2 million in charge-offs related to PCD equipment finance loans purchased in May 2025.

The Company's allowance for credit losses on loans was $118.6 million, or 1.02% of total gross loans, at September 30, 2026, compared to $67.2 million, or 0.82% of total gross loans, at December 31, 2025. The increase in the allowance for credit losses for loans was primarily due to the day 1 Northfield CECL adjustment of $47.1 million recorded as part of the Northfield acquisition.

About Columbia Financial, Inc.

The consolidated financial results include the accounts of Columbia Financial, Inc., its wholly-owned subsidiary Columbia Bank (the "Bank") and the Bank's wholly-owned subsidiaries. Columbia Financial, Inc. is a Maryland corporation organized as Columbia Bank's parent stock holding company. Columbia Bank is a federally chartered savings bank headquartered in Fair Lawn, New Jersey that operates more than 100 full-service banking offices and offers traditional financial services to consumers and businesses in its market area, including select counties in New Jersey, and Brooklyn and Staten Island New York.

Forward Looking Statements

Certain statements herein constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Exchange Act and are intended to be covered by the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Such statements may be identified by words such as “believes,” “will,” “would,” “expects,” “projects,” “may,” “could,” “developments,” “strategic,” “launching,” “opportunities,” “anticipates,” “estimates,” “intends,” “plans,” “targets” and similar expressions. These statements are based upon the current beliefs and expectations of the Company’s management and are subject to significant risks and uncertainties. Actual results may differ materially from those set forth in the forward-looking statements as a result of numerous factors. Factors that could cause such differences to exist include, but are not limited to, adverse conditions in the capital and debt markets and the impact of such conditions on the Company’s business activities; changes in interest rates, higher inflation and their impact on national and local economic conditions; changes in monetary and fiscal policies of the U.S. Treasury, the Board of Governors of the Federal Reserve System and other governmental entities; the impact of tariffs, sanctions and other trade policies of the United States and its global trading counterparts; the impact of changing political conditions or federal government shutdowns; the impact of legal, judicial and regulatory proceedings or investigations, competitive pressures from other financial institutions; the effects of general economic conditions on a national basis or in the local markets in which the Company operates, including changes that adversely affect a borrowers’ ability to service and repay the Company’s loans; the effect of acts of terrorism, war or pandemics, including on our credit quality and business operations, as well as its impact on general economic and financial market conditions; changes in the value of securities in the Company’s portfolio; the success of the balance sheet repositioning transactions we implemented during the third quarter of 2026; changes in loan default and charge-off rates; fluctuations in real estate values; the adequacy of loan loss reserves; decreases in deposit levels necessitating increased borrowing to fund loans and securities; legislative changes and changes in government regulation; changes in accounting standards and practices; the risk that goodwill and intangibles recorded in the Company’s consolidated financial statements will become impaired; cyber-attacks, computer viruses and other technological risks that may breach the security of our systems and allow unauthorized access to confidential information; the inability of third party service providers to perform; demand for loans in the Company’s market area; the Company’s ability to attract and maintain deposits and effectively manage liquidity; risks related to the implementation of acquisitions, dispositions, and restructurings; and the risk that the Company may not be successful in the implementation of its business strategy, or its integration of acquired financial institutions and businesses.

In addition, with respect to the Company’s recently completed acquisition of Northfield Bancorp (“Northfield”), such risks, uncertainties and assumptions, include, among others, the following: (i) the possibility that the anticipated benefits of the

proposed transaction, including anticipated cost savings and strategic gains, are not realized when expected or at all, including as a result of changes in, or problems arising from, general economic and market conditions, interest and exchange rates, monetary policy, laws and regulations and their enforcement, and the degree of competition in the geographic and business areas in which the combined company operates; (ii) the possibility that the integration of the two companies may be more difficult, time-consuming or costly than expected; and (iii) the impact of purchase accounting with respect to the proposed transaction, or any change in the assumptions used regarding the assets acquired and liabilities assumed to determine their fair value and credit marks. Forward-looking statements are subject to numerous risks and uncertainties, including but not limited to, those set forth in Item 1A of the Company's Annual Report on Form 10-K and those set forth in the Company's Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, all as filed with the Securities and Exchange Commission (the “SEC”), which are available at the SEC’s website, www.sec.gov. Should one or more of these risks materialize or should underlying beliefs or assumptions prove incorrect, the Company's actual results could differ materially from those discussed. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this release. The Company disclaims any obligation to publicly update or revise any forward-looking statements to reflect changes in underlying assumptions or factors, new information, future events or other changes, except as required by law.

Non-GAAP Financial Measures

Reported amounts are presented in accordance with U.S. generally accepted accounting principles ("GAAP"). This press release also contains certain supplemental non-GAAP information that the Company’s management uses in its analysis of the Company’s financial results. Specifically, the Company provides measures based on what it believes are its "core" operating results, and relevant performance ratios on a consistent basis and excludes material non-routine items which affect the GAAP reporting of results of operations, and relevant performance ratios. The Company’s management believes that providing this information to analysts and investors allows them to better understand and evaluate the Company’s core financial results for the periods presented. Because non-GAAP financial measures are not standardized, it may not be possible to compare these financial measures with other companies' non-GAAP financial measures having the same or similar names.

The Company also provides measurements and ratios based on tangible stockholders' equity. These measures are commonly utilized by regulators and market analysts to evaluate a company’s financial condition and, therefore, the Company’s management believes that such information is useful to investors.

A reconciliation of GAAP to non-GAAP financial measures are included at the end of this press release. See "Reconciliation of GAAP to Non-GAAP Financial Measures".

COLUMBIA FINANCIAL, INC. AND SUBSIDIARIES

Consolidated Statements of Financial Condition

(In thousands)

September 30, December 31,

2026 2025

Assets (Unaudited)

Cash and due from banks $ 458,686 $ 340,695

Short-term investments 112 111

Total cash and cash equivalents 458,798 340,806

Debt securities available for sale, at fair value 2,816,204 1,122,017

Debt securities held to maturity, at amortized cost (fair value of $853,439, and $367,289 at September 30, 2026 and December 31, 2025, respectively)

912,183 396,233

Equity securities, at fair value 5,440 6,802

Federal Home Loan Bank and Federal Reserve Bank stock, at cost 149,572 64,604

Loans held-for-sale, at fair value 211,410 —

Loans receivable 11,786,760 8,292,010

Less: allowance for credit losses 118,594 67,201

Loans receivable, net 11,668,166 8,224,809

Accrued interest receivable 67,735 41,490

Office properties and equipment, net 113,119 82,985

Bank-owned life insurance 474,888 283,094

Goodwill and intangible assets 191,703 120,302

Other assets 493,275 335,651

Total assets $ 17,562,493 $ 11,018,793

Liabilities and Stockholders' Equity

Liabilities:

Deposits $ 12,561,523 $ 8,444,079

Borrowings 1,496,279 1,183,472

Advance payments by borrowers for taxes and insurance 67,295 45,792

Accrued expenses and other liabilities 272,112 184,722

Total liabilities 14,397,209 9,858,065

Stockholders' equity:

Total stockholders' equity 3,165,284 1,160,728

Total liabilities and stockholders' equity $ 17,562,493 $ 11,018,793

COLUMBIA FINANCIAL, INC. AND SUBSIDIARIES

Consolidated Statements of Income

(In thousands, except per share data)

Three Months Ended

September 30, Nine Months Ended

September 30,

2026 2025 2026 2025

Interest income:

(Unaudited)

Loans receivable

$ 152,636 $ 103,792 $ 358,128 $ 298,548

Debt securities available for sale and equity securities

25,403 9,858 46,941 29,901

Debt securities held to maturity

4,879 2,886 10,486 8,619

Federal funds and interest-earning deposits

7,738 2,623 13,425 7,924

Federal Home Loan Bank and Federal Reserve Bank stock dividends

2,001 1,258 4,799 4,079

Total interest income

192,657 120,417 433,779 349,071

Interest expense:

Deposits

62,840 49,569 155,285 149,058

Borrowings

15,436 13,462 40,803 38,599

Total interest expense

78,276 63,031 196,088 187,657

Net interest income

114,381 57,386 237,691 161,414

Provision for credit losses

1,832 2,344 7,100 7,745

Net interest income after provision for credit losses

112,549 55,042 230,591 153,669

Non-interest (loss) income:

Demand deposit account fees

3,027 2,037 7,164 5,940

Bank-owned life insurance

3,768 2,133 8,682 5,982

Title insurance fees

714 684 2,201 2,191

Loan fees and service charges

1,103 1,570 4,088 4,370

(Loss) gain on securities transactions

(40,849) — (40,849) 336

Change in fair value of equity securities

(447) 714 (1,429) 1,294

(Loss) gain on sale of loans

(7,567) 401 (6,792) 901

Bargain purchase gain, net of tax

25,689 — 25,689 —

(Loss) gain on sale of other real estate owned (1,770) — (1,770) 281

Other non-interest income

2,424 2,328 6,685 7,216

Total non-interest (loss) income

(13,908) 9,867 3,669 28,511

Non-interest expense:

Compensation and employee benefits

43,462 29,248 106,524 86,764

Occupancy

8,663 6,055 22,242 18,208

Federal deposit insurance premiums

2,331 1,783 5,743 5,402

Advertising

915 512 2,228 1,606

Professional fees

2,377 2,590 5,995 8,624

Data processing and software expenses

5,748 4,457 15,366 12,621

Merger-related expenses

30,641 — 33,283 —

Loss on extinguishment of debt 196 — 196 —

Amortization of intangible assets 3,489 560 4,611 1,592

Other non-interest expense, net

(317) (119) (1,779) (980)

Total non-interest expense

97,505 45,086 194,409 133,837

Income before income tax (benefit) expense 1,136 19,823 39,851 48,343

Income tax (benefit) expense (4,095) 4,955 7,034 12,270

Net income

$ 5,231 $ 14,868 $ 32,817 $ 36,073

Earnings per share-basic $ 0.02 $ 0.07 $ 0.14 $ 0.16

Earnings per share-diluted $ 0.02 $ 0.07 $ 0.14 $ 0.16

Weighted average shares outstanding-basic (1)

250,984,115 224,468,686 232,335,137 224,275,297

Weighted average shares outstanding-diluted (1)

251,662,369 224,468,686 232,571,404 224,275,297

(1) As result of the second-step conversion, all prior period share information has been subsequently revised to reflect the 2.2000 exchange ratio.

COLUMBIA FINANCIAL, INC. AND SUBSIDIARIES

Average Balances/Yields

For the Three Months Ended September 30,

2026 2025

Average Balance

Interest and Dividends

Yield / Cost

Average Balance

Interest and Dividends

Yield / Cost

(Dollars in thousands)

Interest-earnings assets:

Loans

$ 11,286,773 $ 152,636 5.37 % $ 8,165,132 $ 103,792 5.04 %

Securities

3,031,705 30,282 3.96 % 1,481,219 12,744 3.41 %

Other interest-earning assets

999,680 9,739 3.87 % 293,903 3,881 5.24 %

Total interest-earning assets

15,318,158 192,657 4.99 % 9,940,254 120,417 4.81 %

Non-interest-earning assets

1,217,777 871,010

Total assets

$ 16,535,935 $ 10,811,264

Interest-bearing liabilities:

Interest-bearing demand

$ 3,142,993 $ 16,824 2.12 % $ 1,904,963 $ 10,685 2.23 %

Money market accounts

1,640,021 8,829 2.14 % 1,369,986 9,763 2.83 %

Savings and club deposits

1,239,886 2,742 0.88 % 640,834 1,056 0.65 %

Certificates of deposit

3,554,073 34,445 3.85 % 2,838,737 28,065 3.92 %

Total interest-bearing deposits

9,576,973 62,840 2.60 % 6,754,520 49,569 2.91 %

FHLB advances

1,404,011 14,471 4.09 % 1,213,787 13,317 4.35 %

Subordinated notes

45,753 834 7.23 % — — — %

Junior subordinated debentures

7,070 131 7.35 % 7,051 145 8.16 %

Total borrowings

1,456,834 15,436 4.20 % 1,220,838 13,462 4.37 %

Total interest-bearing liabilities

11,033,807 $ 78,276 2.81 % 7,975,358 $ 63,031 3.14 %

Non-interest-bearing liabilities:

Non-interest-bearing deposits

2,421,615 1,489,014

Other non-interest-bearing liabilities

306,139 219,406

Total liabilities

13,761,561 9,683,778

Total stockholders' equity

2,774,374 1,127,486

Total liabilities and stockholders' equity

$ 16,535,935 $ 10,811,264

Net interest income

$ 114,381 $ 57,386

Interest rate spread

2.18 % 1.67 %

Net interest-earning assets

$ 4,284,351 $ 1,964,896

Net interest margin

2.96 % 2.29 %

Ratio of interest-earning assets to interest-bearing liabilities

138.83 % 124.64 %

COLUMBIA FINANCIAL, INC. AND SUBSIDIARIES

Average Balances/Yields

For the Nine Months Ended September 30,

2026 2025

Average Balance

Interest and Dividends

Yield / Cost

Average Balance

Interest and Dividends

Yield / Cost

(Dollars in thousands)

Interest-earnings assets:

Loans

$ 9,287,935 $ 358,128 5.16 % $ 8,040,666 $ 298,548 4.96 %

Securities

2,076,233 57,427 3.70 % 1,484,237 38,520 3.47 %

Other interest-earning assets

589,577 18,224 4.13 % 297,563 12,003 5.39 %

Total interest-earning assets

11,953,745 433,779 4.85 % 9,822,466 349,071 4.75 %

Non-interest-earning assets

1,005,767 867,884

Total assets

$ 12,959,512 $ 10,690,350

Interest-bearing liabilities:

Interest-bearing demand

$ 2,348,436 $ 36,752 2.09 % $ 1,967,414 $ 33,121 2.25 %

Money market accounts

1,513,531 26,539 2.34 % 1,328,675 28,425 2.86 %

Savings and club deposits

830,303 4,049 0.65 % 645,055 3,278 0.68 %

Certificates of deposit

3,122,982 87,945 3.77 % 2,795,026 84,234 4.03 %

Total interest-bearing deposits

7,815,252 155,285 2.66 % 6,736,170 149,058 2.96 %

FHLB advances

1,296,659 39,560 4.08 % 1,164,942 38,174 4.38 %

Subordinated notes

15,419 834 7.23 % — — — %

Junior subordinated debentures

7,064 394 7.46 % 7,043 425 8.07 %

Other borrowings

476 15 4.21 % — — — %

Total borrowings

1,319,618 40,803 4.13 % 1,171,985 38,599 4.40 %

Total interest-bearing liabilities

9,134,870 $ 196,088 2.87 % 7,908,155 $ 187,657 3.17 %

Non-interest-bearing liabilities:

Non-interest-bearing deposits

1,849,140 1,455,365

Other non-interest-bearing liabilities

260,569 218,546

Total liabilities

11,244,579 9,582,066

Total stockholders' equity

1,714,933 1,108,284

Total liabilities and stockholders' equity

$ 12,959,512 $ 10,690,350

Net interest income

$ 237,691 $ 161,414

Interest rate spread

1.98 % 1.58 %

Net interest-earning assets

$ 2,818,875 $ 1,914,311

Net interest margin

2.66 % 2.20 %

Ratio of interest-earning assets to interest-bearing liabilities

130.86 % 124.21 %

COLUMBIA FINANCIAL, INC. AND SUBSIDIARIES

Components of Net Interest Rate Spread and Margin

Average Yields/Costs by Quarter

September 30, 2026 June 30, 2026 March 31, 2026 December 31, 2025 September 30, 2025

Yield on interest-earning assets:

Loans

5.37 % 5.01 % 5.01 % 5.03 % 5.04 %

Securities

3.96 3.50 3.38 3.36 3.41

Other interest-earning assets

3.87 4.33 4.78 4.69 5.24

Total interest-earning assets

4.99 % 4.74 % 4.76 % 4.77 % 4.81 %

Cost of interest-bearing liabilities:

Total interest-bearing deposits

2.60 % 2.68 % 2.71 % 2.79 % 2.91 %

Total borrowings

4.20 4.06 4.12 4.25 4.37

Total interest-bearing liabilities

2.81 % 2.90 % 2.92 % 3.01 % 3.14 %

Interest rate spread

2.18 % 1.84 % 1.84 % 1.76 % 1.67 %

Net interest margin

2.96 % 2.44 % 2.42 % 2.36 % 2.29 %

Ratio of interest-earning assets to interest-bearing liabilities

138.83 % 126.11 % 124.59 % 124.84 % 124.64 %

COLUMBIA FINANCIAL, INC. AND SUBSIDIARIES

Selected Financial Highlights

September 30, 2026 June 30, 2026 March 31, 2026 December 31, 2025 September 30, 2025

SELECTED FINANCIAL RATIOS (1):

Return on average assets 0.13 % 0.52 % 0.48 % 0.57 % 0.55 %

Core return on average assets (2)

0.97 % 0.54 % 0.55 % 0.57 % 0.56 %

Return on average equity 0.75 % 4.92 % 4.55 % 5.43 % 5.23 %

Core return on average equity (2)

5.73 % 5.14 % 5.17 % 5.50 % 5.41 %

Core return on average tangible equity (2)

6.20 % 5.71 % 5.75 % 6.14 % 6.04 %

Interest rate spread 2.18 % 1.84 % 1.84 % 1.76 % 1.67 %

Net interest margin 2.96 % 2.44 % 2.42 % 2.36 % 2.29 %

Non-interest (loss) income to average assets (0.33) % 0.39 % 0.25 % 0.31 % 0.36 %

Non-interest expense to average assets 2.34 % 1.76 % 1.75 % 1.70 % 1.65 %

Efficiency ratio 97.05 % 67.01 % 70.73 % 68.42 % 67.04 %

Core efficiency ratio (2)

53.16 % 65.90 % 68.02 % 68.06 % 66.04 %

Average interest-earning assets to average interest-bearing liabilities 138.83 % 126.11 % 124.59 % 124.84 % 124.64 %

Net charge-offs/ (recoveries) to average outstanding loans 0.05 % 0.10 % (0.03) % 0.03 % 0.04 %

(1) Ratios are annualized when appropriate.

(2) See reconciliation of GAAP to non-GAAP financial measures.

ASSET QUALITY DATA:

September 30, 2026 June 30, 2026 March 31, 2026 December 31, 2025 September 30, 2025

(Dollars in thousands)

Non-accrual loans (1)

$ 36,476 $ 42,988 $ 41,375 $ 38,000 $ 32,529

90+ and still accruing

— — — — —

Non-performing loans

36,476 42,988 41,375 38,000 32,529

Real estate owned

— 5,923 5,923 — —

Total non-performing assets

$ 36,476 $ 48,911 $ 47,298 $ 38,000 $ 32,529

Non-performing loans to total gross loans

0.31 % 0.51 % 0.50 % 0.46 % 0.40 %

Non-performing assets to total assets

0.21 % 0.40 % 0.43 % 0.34 % 0.30 %

Allowance for credit losses on loans ("ACL")

$ 118,594 $ 71,065 $ 68,761 $ 67,201 $ 65,659

ACL to total non-performing loans

325.13 % 165.31 % 166.19 % 176.84 % 201.85 %

ACL to gross loans

1.02 % 0.84 % 0.84 % 0.82 % 0.80 %

(1) Excludes loans held-for-sale at September 30, 2026.

LOAN DATA:

September 30, 2026 June 30, 2026 March 31, 2026 December 31, 2025 September 30, 2025

(In thousands)

Real estate loans:

One-to-four family

$ 2,627,567 $ 2,518,768 $ 2,543,588 $ 2,558,252 $ 2,583,162

Multifamily 3,704,346 1,768,395 1,669,232 1,677,613 1,612,105

Commercial real estate

3,247,917 2,573,823 2,472,993 2,513,260 2,532,329

Construction

553,805 502,609 520,753 469,438 465,283

Commercial business loans

1,005,519 831,030 752,246 766,792 771,486

Consumer loans:

Home equity loans and advances

443,303 248,141 249,487 255,126 256,970

Other consumer loans

3,970 2,851 2,850 2,895 2,725

Total gross loans

11,586,427 8,445,617 8,211,149 8,243,376 8,224,060

Purchased credit deteriorated loans

163,004 9,828 10,158 10,442 10,920

Net deferred loan costs, fees and purchased premiums and discounts

37,329 38,165 38,371 38,192 37,580

Allowance for credit losses

(118,594) (71,065) (68,761) (67,201) (65,659)

Loans receivable, net

$ 11,668,166 $ 8,422,545 $ 8,190,917 $ 8,224,809 $ 8,206,901

At September 30, 2026

(Dollars in thousands)

Balance % of Gross Loans

Weighted Average Loan to Value Ratio (1)

Weighted Average Debt Service Coverage (1)

Multifamily Real Estate $ 3,704,346 32.0 % 55.0 % 1.56

Owner Occupied Commercial Real Estate $ 913,044 7.9 % 67.4 % 3.18

Investor Owned Commercial Real Estate:

Retail / Shopping centers $ 627,962 5.4 % 52.5 % 1.61

Mixed Use 445,332 3.8 56.6 1.46

Industrial / Warehouse 551,186 4.8 52.0 1.57

Non-Medical Office 211,467 1.8 50.3 1.78

Medical Office 104,653 0.9 56.7 1.43

Single Purpose 58,592 0.5 63.9 1.36

Other 335,681 2.9 48.6 1.89

Total $ 2,334,873 20.2 % 52.9 % 1.61

Total Multifamily and Commercial Real Estate Loans $ 6,952,263 60.0 % 55.9 % 1.79

(1) Based on the most recent financial information available.

As of September 30, 2026, the Company had approximately $77.0 million in office loans in New York City. As of October 27, 2026, the Company had approximately $164.6 million of rent stabilized multifamily loans in New York City.

DEPOSIT DATA:

September 30, 2026 June 30, 2026 March 31, 2026 December 31, 2025

Balance Weighted Average Rate Balance Weighted Average Rate Balance Weighted Average Rate Balance Weighted Average Rate

(Dollars in thousands)

Non-interest-bearing demand $ 2,327,457 — % $ 1,555,833 — % $ 1,508,030 — % $ 1,517,399 — %

Interest-bearing demand 3,402,812 2.07 2,844,989 1.37 1,882,987 1.86 1,985,871 1.99

Money market accounts 1,719,373 2.36 1,409,504 2.48 1,451,274 2.43 1,465,028 2.59

Savings and club deposits 1,391,044 0.93 636,566 0.42 625,001 0.42 623,444 0.47

Certificates of deposit 3,720,837 3.66 3,055,173 3.69 2,904,722 3.71 2,852,337 3.80

Total deposits $ 12,561,523 2.07 % $ 9,502,065 1.99 % $ 8,372,014 2.16 % $ 8,444,079 2.23 %

CAPITAL RATIOS:

September 30,

December 31,

2026 (1)

2025

Company:

Total capital (to risk-weighted assets)

25.75 % 14.92 %

Tier 1 capital (to risk-weighted assets)

24.29 % 14.03 %

Common equity tier 1 capital (to risk-weighted assets)

24.24 % 13.94 %

Tier 1 capital (to adjusted total assets)

18.39 % 10.27 %

Columbia Bank:

Total capital (to risk-weighted assets)

19.77 % 14.09 %

Tier 1 capital (to risk-weighted assets)

18.81 % 13.20 %

Common equity tier 1 capital (to risk-weighted assets)

18.81 % 13.20 %

Tier 1 capital (to adjusted total assets)

14.23 % 9.67 %

(1) Estimated ratios at September 30, 2026

RECONCILIATION OF GAAP TO NON-GAAP FINANCIAL MEASURES

Book and Tangible Book Value per Share

September 30, December 31,

2026 2025

(Dollars in thousands)

Total stockholders' equity $ 3,165,284 $ 1,160,728

Less: goodwill (110,715) (110,715)

Less: core deposit intangible (78,763) (6,946)

Total tangible stockholders' equity $ 2,975,806 $ 1,043,067

Shares outstanding 269,547,660 103,984,649

Cash dividends paid per share $ 0.05 $ —

Book value per share $ 11.74 $ 11.16

Tangible book value per share $ 11.04 $ 10.03

RECONCILIATION OF GAAP TO NON-GAAP FINANCIAL MEASURES (continued)

Reconciliation of Core Net Income

Three Months Ended September 30, Nine Months Ended September 30,

2026 2025 2026 2025

(In thousands)

Net income $ 5,231 $ 14,868 $ 32,817 $ 36,073

Add/less: loss (gain) on securities transactions, net of tax 29,003 — 29,003 (251)

Add: loss on sale of loans , net of tax(1)

4,897 — 4,897 —

Less: bargain purchase gain, net of tax (25,689) — (25,689) —

Add: severance expense, net of tax 1,091 503 1,091 1,020

Add: merger-related expenses, net of tax 25,942 — 28,371 —

Add: loss on extinguishment of debt, net of tax 139 — 139 —

Add: litigation expenses, net of tax — — — 242

Core net income $ 40,614 $ 15,371 $ 70,629 $ 37,084

(1) Loss on sale of loans includes only Northfield loan sales.

Return on Average Assets

Three Months Ended September 30, Nine Months Ended September 30,

2026 2025 2026 2025

(Dollars in thousands)

Net income $ 5,231 $ 14,868 $ 32,817 $ 36,073

Average assets $ 16,535,935 $ 10,811,264 $ 12,959,512 $ 10,690,350

Return on average assets 0.13 % 0.55 % 0.34 % 0.45 %

Core net income $ 40,614 $ 15,371 $ 70,629 $ 37,084

Core return on average assets 0.97 % 0.56 % 0.73 % 0.46 %

RECONCILIATION OF GAAP TO NON-GAAP FINANCIAL MEASURES (continued)

Return on Average Equity

Three Months Ended September 30, Nine Months Ended September 30,

2026 2025 2026 2025

(Dollars in thousands)

Total average stockholders' equity $ 2,774,374 $ 1,127,486 $ 1,714,933 $ 1,108,284

Add/less: loss (gain) on securities transactions, net of tax 29,003 — 29,003 (251)

Add: loss on sale of loans, net of tax(1)

4,897 — 4,897 —

Less: bargain purchase gain, net of tax (25,689) — (25,689) —

Add: severance expense, net of tax 1,091 503 1,091 1,020

Add: merger-related expenses, net of tax 25,942 — 28,371 —

Add: loss on extinguishment of debt, net of tax 139 — 139 —

Add: litigation expenses, net of tax — — — 242

Core average stockholders' equity $ 2,809,757 $ 1,127,989 $ 1,752,745 $ 1,109,295

Return on average equity 0.75 % 5.23 % 2.56 % 4.35 %

Core return on core average equity 5.73 % 5.41 % 5.39 % 4.47 %

(1) Loss on sale of loans includes only Northfield loan sales.

Return on Average Tangible Equity

Three Months Ended September 30, Nine Months Ended September 30,

2026 2025 2026 2025

(Dollars in thousands)

Total average stockholders' equity $ 2,774,374 $ 1,127,486 $ 1,714,933 $ 1,108,284

Less: average goodwill (110,715) (110,715) (110,715) (110,715)

Less: average core deposit intangible (65,493) (7,742) (26,401) (8,252)

Total average tangible stockholders' equity $ 2,598,166 $ 1,009,029 $ 1,577,817 $ 989,317

Core return on average tangible equity 6.20 % 6.04 % 5.98 % 5.01 %

RECONCILIATION OF GAAP TO NON-GAAP FINANCIAL MEASURES (continued)

Efficiency Ratios

Three Months Ended September 30, Nine Months Ended September 30,

2026 2025 2026 2025

(Dollars in thousands)

Net interest income $ 114,381 $ 57,386 $ 237,691 $ 161,414

Non-interest (loss) income (13,908) 9,867 3,669 28,511

Total income $ 100,473 $ 67,253 $ 241,360 $ 189,925

Non-interest expense $ 97,505 $ 45,086 $ 194,409 $ 133,837

Efficiency ratio 97.05 % 67.04 % 80.55 % 70.47 %

Non-interest (loss) income $ (13,908) $ 9,867 $ 3,669 $ 28,511

Add/less: loss (gain) on securities transactions 40,849 — 40,849 (336)

Add: loss on sale of loans (1)

6,897 — 6,897 —

Less: bargain purchase gain, net of tax (25,689) — (25,689) —

Core non-interest income $ 8,149 $ 9,867 $ 25,726 $ 28,175

Non-interest expense $ 97,505 $ 45,086 $ 194,409 $ 133,837

Less: severance expense (1,536) (670) (1,536) (1,365)

Less: merger-related expenses (30,641) — (33,283) —

Less: loss on extinguishment of debt (196) — (196) —

Less: litigation expenses — — — (325)

Core non-interest expense $ 65,132 $ 44,416 $ 159,394 $ 132,147

Core efficiency ratio 53.16 % 66.04 % 60.51 % 69.70 %

(1) Loss on sale of loans includes only Northfield loan sales.

ACQUISITION DATE-FAIR VALUE BALANCE SHEET

The following table summarizes the estimated fair values of the assets acquired and the liabilities assumed at the date of the acquisition for Northfield, net of the total consideration paid:

At July 20, 2026

(In thousands)

Amount Estimated Fair Value

Total Purchase Price $ 578,823

Acquired Equity $ 681,816

Fair Value Marks:

Debt securities held to maturity (425)

Loans receivable, yield (150,538)

Loans receivable, credit (86,590)

Allowance for credit losses 39,441

Core deposit intangibles 76,167

Office land and buildings 12,973

Leases (550)

Certificates of deposit 2,364

Borrowings 2,613

Subordinated debentures 1,860

Post-Retirement benefits (BOLI) (293)

Taxes 25,674

Less: Fair value of net assets $ 604,512

Bargain purchase gain, net of tax $ (25,689)

The calculation of the bargain purchase gain is subject to change for up to one year after the date of acquisition as additional information relative to the closing date estimates and uncertainties become available. As the Company finalizes its review of the acquired assets and liabilities, certain adjustments to the recorded carrying values may be required.

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