Exhibit 99.1

FOR IMMEDIATE RELEASE

OCEANFIRST FINANCIAL CORP.

ANNOUNCES QUARTERLY

FINANCIAL RESULTS

TOMS RIVER, NEW JERSEY, April 23, 2015…OceanFirst Financial Corp. (NASDAQ:“OCFC”), (the “Company”), the holding company for OceanFirst Bank (the “Bank”), today announced that diluted earnings per share increased to $0.32 for the quarter ended March 31, 2015, as compared to $0.28 for the corresponding prior year period.

Highlights for the quarter are described below.

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Chief Executive Officer and President Christopher D. Maher commented on the results, “Commercial loan growth remained strong and we are particularly pleased to note the contribution from new officers located at the Loan Production Office in Mercer County, which was opened during the first quarter. The Bank is committed to maintaining conservative credit standards and has enhanced our team with the addition of a deeply experienced Chief Credit Officer. Rounding out the quarter was solid core deposit growth and a demonstrated commitment to expense discipline.” Mr. Maher provided further remarks about the Colonial announcement, “We are continuing to work through the regulatory approval process. This acquisition provides a wonderful opportunity to expand our presence in Monmouth County and we look forward to meeting the full financial needs of the Colonial American customers.”

The Company also announced that the Board of Directors declared its seventy-third consecutive quarterly cash dividend on common stock. The dividend for the quarter ended March 31, 2015 of $0.13 per share, representing a 41% payout ratio, will be paid on May 15, 2015 to shareholders of record on May 4, 2015.

The Bank expects to open an additional branch in Jackson Township late in the second quarter of 2015. The new branch design will be operated by universal bankers and employ advanced technology in the form of interactive teller machines, resulting in a modest staffing complement.

Results of Operations

Net income for the quarter ended March 31, 2015 was $5.3 million, or $0.32 per diluted share, as compared to net income of $4.7 million, or $0.28 per diluted share, for the corresponding prior year period and compared to $4.9 million and $0.30 per diluted share for the prior linked quarter. The increase over the previous year period was primarily due to lower operating expenses,

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higher non-interest income, a reduction in the provision for loan losses and a reduction in average shares outstanding. The increase over the prior linked quarter was primarily due to lower operating expenses and a reduction in the provision for loans losses, partly offset by a reduction in non-interest income.

Net interest income was unchanged at $18.1 million for both the quarter ended March 31, 2015 and the same prior year period, as a decrease in the net interest margin was offset by an increase in average interest-earning assets. The net interest margin decreased to 3.24% for the quarter ended March 31, 2015, from 3.36% for the same prior year period. The yield on average interest-earning assets decreased to 3.60% for the quarter ended March 31, 2015, as compared to 3.68% in the same prior year period, while the cost of average interest-bearing liabilities increased to 0.45%, as compared to 0.37% in the prior year period, as the Company extended its borrowed funds into higher-costing longer-term maturities.

Net interest income for the quarter ended March 31, 2015 increased $109,000, as compared to the prior linked quarter. A decrease in the net interest margin to 3.24%, from 3.27%, was offset by an increase in average interest-earning assets of $34.1 million. The yield on average interest-earning assets declined to 3.60% for the quarter ended March 31, 2015, from 3.64% for the prior linked quarter, while the cost of average interest-bearing liabilities was unchanged at 0.45%. Despite the decline in the yield on interest-earning assets as compared to both the prior linked quarter and the same prior year quarter, the asset yield still benefited from the growth in average loans receivable of $67.9 million, as compared to the prior linked quarter, and $145.4 million, as compared to the same prior year quarter.

For the quarter ended March 31, 2015, the provision for loan losses was $375,000, as compared to $530,000 for the corresponding prior year period. Net charge-offs decreased to $273,000 for the quarter ended March 31, 2015, as compared to net charge-offs of $526,000 in the

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corresponding prior year period. The provision exceeded net charge-offs by $102,000 partially due to loan growth. The provision for loan losses also decreased as compared to $825,000 in the prior linked quarter, consistent with the decline in net charge-offs to $273,000 from $818,000.

For the quarter ended March 31, 2015, other income increased to $4.0 million, as compared to $3.8 million in the same prior year period. In the fourth quarter of 2014, the Company sold the servicing rights on a majority of residential mortgage loans serviced for the Federal agencies, recognizing a gain of $408,000. A smaller, supplemental sale in the first quarter of 2015 resulted in a gain of $81,000. The sale of loan servicing caused a decrease of $176,000 in loan servicing income, as compared to the same prior year quarter but also reduced operating expenses by a similar amount. For the quarter ended March 31, 2015, the net gain on sales of loans available for sale increased $61,000, as compared to the same prior year period.

For the quarter ended March 31, 2015, other income decreased $634,000 as compared to the prior linked quarter, due to decreases of $327,000 in the net gain on sale of loan servicing, $218,000 in fees and service charges, $93,000 in the net gain on sales of investment securities, $92,000 in Bankcard services revenue and $71,000 in loan servicing income. The decreases were partly offset by an improvement in the net gain (loss) from other real estate operations of $247,000.

Operating expenses decreased to $13.7 million for the quarter ended March 31, 2015, as compared to $14.1 million in the same prior year period. Marketing expense decreased $258,000 for the quarter ended March 31, 2015, as compared to the same prior year period due to the seasonality of promotions and a significant campaign in the prior year period. Additionally, compensation and employee benefits expense decreased $146,000, as compared to the same prior year period. Other operating expenses for the quarter ended March 31, 2015 include $50,000 in non-recurring merger related expenses relating to the pending acquisition of Colonial. For the quarter ended March 31, 2015, operating expenses decreased $658,000, as compared to the prior

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linked quarter primarily due to a decrease of $326,000 in compensation and employee benefits and a $270,000 decrease in professional fees, partly related to legal costs associated with loan collection efforts. These costs declined due to the bulk sale of non-performing loans in the third quarter of 2014 and the sale of servicing rights.

The provision for income taxes was $2.7 million for the quarter ended March 31, 2015, as compared to $2.6 million for the same prior year period. The effective tax rate was 34.3% for the quarter ended March 31, 2015, as compared to 35.3% in the same prior year period and 33.6% in the prior linked quarter. The reduction in the effective tax rate from the prior year is due to higher levels of tax exempt interest income.

Financial Condition

Total assets increased by $27.4 million to $2,384.1 million at March 31, 2015, from $2,356.7 million at December 31, 2014. Loans receivable, net, increased by $48.0 million, to $1,736.8 million at March 31, 2015 from $1,688.8 million at December 31, 2014, primarily due to growth in commercial loans of $41.3 million. Additionally, on March 31, 2015 the Company purchased a pool of performing, locally-originated, one-to-four family, non-conforming mortgage loans for $7.2 million. The increase in loans receivable, net was partly offset by a decrease in total securities of $16.4 million.

Deposits increased by $80.8 million, to $1,800.9 million at March 31, 2015, from $1,720.1 million at December 31, 2014, partly due to an increase in business deposits of $35.2 million, demonstrating the value of relationship based lending. The deposit growth funded a decrease in FHLB advances of $53.5 million, to $251.8 million at March 31, 2015, from $305.2 million at December 31, 2014. Stockholders’ equity increased to $220.3 million at March 31, 2015, as compared to $218.3 million at December 31, 2014, as net income for the period was partly offset by

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the repurchase of 110,143 shares of common stock for $1.9 million (average cost per share of $17.08) and the cash dividend on common stock. At March 31, 2015, there were 508,255 shares available for repurchase under the stock repurchase program adopted in July of 2014. Tangible stockholders’ equity per common share was $13.06 at March 31, 2015, as compared to $12.91 at December 31, 2014.

Asset Quality

The Company’s non-performing loans totaled $19.4 million at March 31, 2015, a $1.1 million increase from December 31, 2014 but a $25.9 million decrease from March 31, 2014. The reduction from the prior year was due to the bulk sale of $23.1 million in non-performing loans in the third quarter of 2014.

Conference Call

As previously announced, the Company will host an earnings conference call on Friday, April 24, 2015 at 11:00 a.m. Eastern time. The direct dial number for the call is (888) 338-7143. For those unable to participate in the conference call, a replay will be available. To access the replay, dial (877) 344-7529, Replay Conference Number 10063054 from one hour after the end of the call until July 23, 2015. The conference call, as well as the replay, are also available (listen-only) by internet webcast at www.oceanfirst.com in the Investor Relations section.

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OceanFirst Financial Corp.’s subsidiary, OceanFirst Bank, founded in 1902, is a community bank with $2.4 billion in assets and twenty-three branches located in Ocean, Monmouth and Middlesex Counties, New Jersey. The Bank delivers commercial and residential financing

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solutions, wealth management, and deposit services throughout the central New Jersey region and is the largest and oldest financial institution headquartered in Ocean County, New Jersey.

OceanFirst Financial Corp.’s press releases are available by visiting us at www.oceanfirst.com.

Forward-Looking Statements

In addition to historical information, this news release contains certain forward-looking statements within the meaning of the Private Securities Reform Act of 1995 which are based on certain assumptions and describe future plans, strategies and expectations of the Company. These forward-looking statements are generally identified by use of the words “believe,” “expect,” “intend,” “anticipate,” “estimate,” “project,” “will,” “should,” “may,” “view,” “opportunity,” “potential,” or similar expressions or expressions of confidence. The Company’s ability to predict results or the actual effect of future plans or strategies is inherently uncertain. Factors which could have a material adverse effect on the operations of the Company and its subsidiaries include, but are not limited to: changes in interest rates, general economic conditions, levels of unemployment in the Bank’s lending area, real estate market values in the Bank’s lending area, future natural disasters and increases to flood insurance premiums, the level of prepayments on loans and mortgage-backed securities, legislative/regulatory changes, monetary and fiscal policies of the U.S. Government including policies of the U.S. Treasury and the Board of Governors of the Federal Reserve System, the quality or composition of the loan or investment portfolios, demand for loan products, deposit flows, competition, demand for financial services in the Company’s market area and accounting principles and guidelines. These risks and uncertainties are further discussed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014 and subsequent securities filings and should be considered in evaluating forward-looking statements and undue reliance should not be placed on such statements. The Company does not undertake, and specifically disclaims any obligation, to publicly release the result of any revisions which may be made to any forward-looking statements to reflect events or circumstances after the date of such statements or to reflect the occurrence of anticipated or unanticipated events.

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OceanFirst Financial Corp.

CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION

(dollars in thousands, except per share amounts)

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OceanFirst Financial Corp.

CONSOLIDATED STATEMENTS OF INCOME

(in thousands, except per share amounts)

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OceanFirst Financial Corp.

SELECTED CONSOLIDATED FINANCIAL DATA

(in thousands, except per share amounts)

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OceanFirst Financial Corp.

SELECTED LOAN AND DEPOSIT DATA

(in thousands)

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OceanFirst Financial Corp.

ANALYSIS OF NET INTEREST INCOME

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