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

December 5, 2017

Date of Report (Date of earliest event reported)

PEAPACK-GLADSTONE FINANCIAL CORPORATION

(Exact name of Registrant as Specified in its Charter)

New Jersey

(State or Other Jurisdiction

of Incorporation)

500 Hills Drive, Suite 300

Bedminster, New Jersey 07921-1538

(Address of principal executive offices)

(908) 234-0700

(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:

Indicate by check mark whether the registrant is an emerging growth company as defined in 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.  ☐

On December 5, 2017, Peapack-Gladstone Financial Corporation (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with Sandler O’Neill & Partners, L.P., as representative of the underwriters named therein, with respect to the sale of $35.0 million in principal amount of 4.75% fixed-to-floating subordinated notes due December 15, 2027 (the “Notes”). The Underwriting Agreement includes customary representations, warranties and covenants by the Company. The Company also agreed to indemnify the underwriters against certain liabilities under the Securities Act of 1933, as amended. The foregoing description of the Underwriting Agreement is qualified in its entirety by reference to the Underwriting Agreement, a copy of which is attached hereto as Exhibit 1.1 and incorporated herein by reference.

On December 5, 2017, the Company priced the public offering of the Notes. A copy of the press release announcing the pricing of the offering is included herewith as Exhibit 99.1 and is incorporated herein by reference.

(d) Exhibits.

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SIGNATURES

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

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