Exhibit 99.1

PCSB Financial Corporation Announces Fourth Fiscal Quarter and Year End Financial Results and

Declares Quarterly Cash Dividend

Yorktown Heights, New York; August 4, 2022 – PCSB Financial Corporation (the “Company”) (NASDAQ: PCSB), parent of PCSB Bank (the "Bank"), today announced net income of $3.5 million, or $0.25 per diluted share, for the three months ended June 30, 2022, compared to $3.5 million, or $0.24 per diluted share, for the three months ended March 31, 2022 and $3.4 million, or $0.23 per diluted share, for the three months ended June 30, 2021.

Net income was $14.9 million, or $1.04 per diluted share, for the year ended June 30, 2022, compared to $12.4 million, or $0.84 per diluted share, for the year ended June 30, 2021. Results for the three months and year ended June 30, 2022 include merger-related expenses of $1.2 million and $1.3 million, or $0.07 and $0.08 per diluted share, net of tax, respectively. Results for the year ended June 30, 2021 include a benefit for loan losses of $673,000, or $0.04 per diluted share, net of tax, which includes the release of the qualitative reserves established in the prior fiscal year associated with the COVID-19 pandemic.

On May 23, 2022, the Company and Brookline Bancorp, Inc. (“Brookline”), the holding company of Brookline Bank and Bank Rhode Island, entered into an Agreement and Plan of Merger (the “Merger Agreement”). Pursuant to the Merger Agreement, PCSB will merge with and into Brookline, with Brookline as the surviving corporation (the “Merger”). Following the Merger, PCSB Bank will operate as a separate bank subsidiary of Brookline. The consummation of the Merger is subject to customary closing conditions, including the receipt of regulatory approvals and approval by PCSB’s stockholders. The Merger is currently expected to be completed in the fourth quarter of 2022.

On July 27, 2022, the Board of Directors declared a regular quarterly cash dividend of $0.07 per share. The dividend is payable on or about September 9, 2022 to shareholders of record as of the close of business on August 26, 2022.

Fourth Quarter Highlights

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President’s Comments

Joseph D. Roberto, Chairman, President & Chief Executive Officer of PCSB Financial Corporation, commented, “We are pleased with the Company’s solid operating and financial results for our fiscal fourth quarter and year ended June 30, 2022. Annualized loan growth of 13.6% for the fourth quarter and 8.1% year over year reflects our ability to originate quality loans within our strong market footprint. The loan growth, combined with a balance sheet well-positioned to take advantage of higher interest rates, has led to higher net interest income, margins and earnings. Core net income of $4.4 million for the fourth quarter reflects a 34.1% increase over the linked quarter while core net income of $14.2 million for the year reflects a 33.1% increase over the prior year. Although economic headwinds continue to be challenging, our outlook remains positive as the PCSB team continues working to create sustainable value for our shareholders.”

Mr. Roberto added “We are excited about our pending merger with Brookline and look forward to becoming part of a larger organization, which will benefit all of our shareholders. I want to thank our staff for their dedication and hard work, especially during this time of transition. In addition to operating PCSB Bank in a business-as-usual manner for our customers, they have also been working hard to ensure that we have a seamless transition into Brookline’s organization.”

Income Statement Summary

Net income for the current quarter was $3.5 million, which increased $29,000 from the linked quarter and $93,000 from the prior year quarter. The change from the linked quarter is primarily due to a $1.2 million increase in net interest income, a $165,000 increase in noninterest income and a $77,000 decrease in provision for loan losses, partially offset by increases of $1.3 million in noninterest expense and $113,000 in income tax expense. The change from the prior year quarter is primarily due to increases of $1.3 million in net interest income and $520,000 in noninterest income, partially offset by increases of $1.4 million in noninterest expense, $204,000 in provision for loan losses and $170,000 in income tax expense.

Net interest income was $13.9 million for the current quarter, increases of $1.2 million, or 9.5%, compared to the linked quarter and $1.3 million, or 10.7%, compared to the prior year quarter. The increase compared to the linked quarter is primarily the result of a 20 basis point increase in the tax equivalent net interest margin and a $41.5 million, or 2.3%, increase in average interest-earning assets. The increase in net interest income compared to the prior year period is primarily the result of a 19 basis point increase in the tax equivalent net interest margin and a $75.7 million, or 4.2%, increase in average interest-earning assets.

The Company recognized PPP loan interest and origination fee income (net of costs) of $36,000 in the current quarter, compared to $266,000 in the linked quarter and $516,000 in the prior year quarter. As of June 30, 2022, the Company had 5 outstanding PPP loans with balances totaling $1.9 million. Unearned origination fees (net of costs) were $85,000 as of June 30, 2022, which will be recognized in income over the remaining lives of the loans. PPP loan forgiveness is substantially complete as of June 30, 2022.

The tax equivalent net interest margin was 3.00% for the current quarter, reflecting increases of 20 basis points compared to 2.80% in the linked quarter and 19 basis points compared to 2.81% in the prior year quarter. Adjusted net interest margin, which excludes the effects of loan prepayment income and PPP loan interest and fees, was 2.94% for the current quarter compared to 2.70% in the linked quarter and 2.53% in the prior year quarter. Margin improvement compared to the linked quarter and prior year quarter was the result of a reduction in the cost of funds, driven by a lower costing deposit mix, as well as an increased asset yields, driven by higher market interest rates. Reconciliations of GAAP to non-GAAP financial measures are included at the end of this release.

Tax equivalent yield on interest-earning assets for the current quarter was 3.31%, increases of 19 basis points from the linked quarter and 5 basis point from the prior year quarter. Excluding the effects of non-recurring PPP loan income and loan prepayment income, the tax equivalent yield on interest-earning assets for the current quarter was 3.25%, increases of 22 basis points from the linked quarter and 27 basis points from the same quarter last year. The increase in yield compared to the prior year quarter is a result of higher market interest rates driving higher yield on cash liquidity and adjustable rate loan and investment assets, along with higher investment and loan re-investment rates. Compared to the linked quarter, the increase in yield was the result of higher market interest rates and a more profitable asset mix.

The cost of interest-bearing deposits was 0.35% for the current quarter, decreases of 2 basis points and 13 basis points from 0.37% and 0.48% in the linked quarter and prior year quarter, respectively. In response to lower market interest rates and increased liquidity levels, deposit rate reductions have been implemented throughout the last 2 years, the effects of which continue to be realized. Recent increases by the Federal Reserve in the federal funds rate beginning in March 2022 and continuing throughout the current quarter have not yet resulted in deposit cost increases, due to limited competitive pricing

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pressures and elevated liquidity in the banking sector. As of quarter end, the weighted average cost of interest-bearing deposits was 0.34%. The cost of interest-bearing liabilities was 0.41% for the current quarter, decreases of 2 basis points from 0.43% in the linked quarter and 18 basis points from 0.59% in the prior year quarter. Over the next 12 months, the Company has $40.0 million of wholesale funding maturing, comprised of FHLB advances and brokered time deposits, with a weighted average cost of 1.79%.

The provision for loan losses was $209,000 for current quarter, compared to $286,000 for the linked quarter and $5,000 for the prior year quarter. Recoveries, net of charge-offs, were $7,000 for the current quarter compared to charge-offs, net of recoveries, of $4,000 for the linked quarter and recoveries, net of charge-offs, of $11,000 for the prior year quarter. Non-performing loans as a percent of total loans receivable (excluding PPP loans) was 0.56% as of June 30, 2022, an increase from 0.48% as of June 30, 2021 but a decrease from 0.61% as of March 31, 2022. Substandard loans were $12.6 million as of June 30, 2022, a decrease from $23.1 million as of March 31, 2022 and $21.6 million as of June 30, 2021, driven primarily by sustained positive borrower operational and payment performance following the end of COVID-19 related payment deferrals. The Company had no loans remaining on COVID-19 related payment deferral as of June 30, 2022, compared to $27.3 million, or 2.21% of gross loans, as of June 30, 2021.

Noninterest income of $1.1 million for the current quarter increased $165,000 compared to the linked quarter and $520,000 compared to the prior year quarter. The increase compared to the linked quarter was primarily due to increases of $119,000 in swap income and $52,000 in fees and services charges. The increase compared to the prior year quarter was primarily due to increases of $452,000 in swap income, $52,000 in fees and service charges and $18,000 in bank-owned life insurance income.

Noninterest expense of $10.3 million for the current quarter increased $1.3 million compared to the linked quarter and $1.4 million compared to the prior year quarter. Excluding merger-related expenses of $1.2 million in the current quarter and $86,000 in the linked quarter, noninterest expenses increased $232,000, or 2.6%, compared to the linked quarter and $235,000, or 2.7%, compared to the same quarter last year. Excluding merger-related expenses, the $235,000 increase compared to the prior year quarter was primarily due to higher salaries and benefits, marketing and communication and data processing costs which were partially offset by lower pension costs. The $232,000 increase compared to the linked quarter is the result of higher salaries and benefits, partially offset by lower professional fees and pension costs.

The effective income tax rate was 22.8% for the current quarter, as compared to 21.0% for the linked quarter and 20.3% for the prior year quarter. The increase for the current quarter is primarily due to non-deductible merger-related expenses. Excluding such expenses, the effective tax rate for the quarter is 20.2%.

Balance Sheet Summary

Total assets increased $114.2 million to $1.99 billion at June 30, 2022 as compared to June 30, 2021, primarily due to increases of $99.9 million in net loans receivable and $52.1 million in investment securities, partially offset by a $40.8 million decrease in cash and cash equivalents. Net loans receivable increased $99.9 million, or 8.1%, and $135.0 million or 11.3% excluding PPP loans. The increase was primarily the result of increases in commercial mortgage loans and construction loans of $115.5 million and $10.7 million, respectively, partially offset by decreases in commercial loans and residential mortgage loans of $14.4 million and $10.1 million, respectively. The decrease in commercial loans includes a decrease in PPP loans of $35.1 million, driven by forgiveness and paydowns, largely offset by a net increase of $20.7 million in all other commercial loans. The increase in investment securities was the result of the Company deploying excess liquidity and included increases of $27.2 million in state and municipal securities, $14.1 million in U.S. government and agency bonds, $5.7 million in mortgage-backed securities, and $5.1 million in corporate securities.

Total liabilities increased $111.6 million to $1.71 billion at June 30, 2022 as compared to June 30, 2021 as an increase of $134.6 million in deposits was partially offset by decreases of $17.6 million in FHLB advances and $5.4 million in all other liabilities. The $134.6 million, or 9.0% increase in deposits includes increases in NOW, money market, demand and savings accounts of 37.1%, 19.9%, 12.0% and 6.1%, respectively, partially offset by a 12.6% decrease in time deposits. Current quarter deposit growth of $1.5 million includes the run-off of approximately $38.1 million of transient deposits as of March 31, 2022 expected to outflow in the current quarter.

Total shareholders’ equity increased $2.6 million to $277.2 million at June 30, 2022 as compared to $274.6 million as of June 30, 2021. The increase for the year was primarily due to net income of $14.9 million and $5.0 million of stock-based compensation and reduction in unearned ESOP shares for plan shares earned during the period, partially offset by the repurchase of $8.2 million (443,788 shares) of common stock, $5.5 million of other comprehensive losses related primarily

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to unrealized losses on investment securities driven by higher market interest rates and $3.6 million of cash dividends declared and paid.

At June 30, 2022, the Company’s book value per share and tangible book value per share were $18.07 and $17.67, respectively, compared to $17.41 and $17.01, respectively, at June 30, 2021. Reconciliations of book value per share (GAAP measure) to tangible book value per share (non-GAAP measure) appear at the end of this release. At June 30, 2022, the Bank was considered “well capitalized” under applicable regulatory guidelines.

About PCSB Financial Corporation and PCSB Bank

PCSB Financial Corporation is the bank holding company for PCSB Bank. PCSB Bank is a New York-chartered commercial bank that has served the banking needs of its customers in the Lower Hudson Valley of New York State since 1871. It operates from its executive offices/headquarters and 14 branch offices located in Dutchess, Putnam, Rockland and Westchester Counties in New York.

This News Release contains a number of forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These statements may be identified by use of words such as "anticipate," "believe," "could," "estimate," "expect," "intend," "may," "outlook," "plan," "potential," "predict," "project," "should," "will," "would" and similar terms and phrases, including references to assumptions.

Forward-looking statements are based upon various assumptions and analyses made by the Company in light of management's experience and its perception of historical trends, current conditions and expected future developments, as well as other factors it believes are appropriate under the circumstances. These statements are not guarantees of future performance and are subject to risks, uncertainties and other factors (many of which are beyond the Company's control) that could cause actual results to differ materially from future results expressed or implied by such forward-looking statements. These factors include, without limitation, the following: the duration, extent and severity of the COVID-19 pandemic, including its impact on our business and operations, the impact of lost fee revenue and increased operating expenses, as well as its effect on our customers and issuers of securities, including their ability to make timely payments on obligations, service providers and on economies and markets more generally, the timing and occurrence or non-occurrence of events may be subject to circumstances beyond the Company’s control; there may be increases in competitive pressure among financial institutions or from non-financial institutions; changes in the interest rate environment may reduce asset value and interest margins; changes in deposit flows, loan demand or real estate values may adversely affect the Company's business; changes in accounting principles, policies or guidelines may cause the Company’s financial condition to be perceived differently; changes in corporate and/or individual income tax laws may adversely affect the Company's financial condition or results of operations; general economic conditions, either nationally or locally in some or all areas in which the Company conducts business, or conditions in the securities markets or the banking industry may be less favorable than the Company currently anticipates; legislation or regulatory changes may adversely affect the Company’s business; technological changes may be more difficult or expensive than the Company anticipates; success or consummation of new business initiatives may be more difficult or expensive than the Company anticipates; or litigation or other matters before regulatory agencies, whether currently existing or commencing in the future, may delay the occurrence or non-occurrence of events longer than the Company anticipates. The Company assumes no obligation to update any forward-looking statements except as may be required by applicable law or regulation.

Contact: Joseph D. Roberto

Chairman, President and Chief Executive Officer

(914) 248-7272

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PCSB Financial Corporation and Subsidiaries

Consolidated Balance Sheets (unaudited)

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PCSB Financial Corporation and Subsidiaries

Consolidated Statements of Operations (unaudited)

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PCSB Financial Corporation and Subsidiaries

Net Interest Margin Analysis (unaudited)

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PCSB Financial Corporation and Subsidiaries

Net Interest Margin Analysis (unaudited)

(dollar amounts in thousands)