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): February 9, 2018

Terreno Realty Corporation

(Exact name of registrant as specified in its charter)

101 Montgomery Street, Suite 200

San Francisco, CA 94104

(Address of principal executive offices) (Zip Code)

(415) 655-4580

(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 (see General Instruction A.2. below):

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

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 February 9, 2018, Terreno Realty Corporation (the “Company”) filed with the Securities and Exchange Commission (the “SEC”) a shelf registration statement on Form S-3, which became immediately effective upon filing and which replaced the Company’s previous shelf registration statement on Form S-3 (File No. 333-203030) filed with the SEC on March 26, 2015.

In connection with the filing of the new shelf registration statement, the Company also filed with the SEC a new prospectus supplement, dated February 9, 2018, with respect to the Company’s existing “at the market” equity offering program (the “ATM Program”), pursuant to which the Company may issue and sell shares of its common stock having an aggregate offering price of up to $200,000,000, from time to time through each of KeyBanc Capital Markets Inc., Robert W. Baird & Co. Incorporated, BTIG, LLC, Goldman Sachs & Co. LLC, Jefferies LLC, JMP Securities LLC, MUFG Securities Americas Inc., Sandler O’Neill & Partners, L.P. and Stifel, Nicolaus & Company, Incorporated as sales agents (collectively, the “Sales Agents”) pursuant to separate Equity Distribution Agreements, dated August 4, 2017, between the Company and each of the Sales Agents. The Company has sold shares of common stock having an aggregate offering price of $109,906,637 under the ATM Program. Accordingly, as of the date of the new prospectus supplement, shares of common stock having an aggregate offering price of up to $90,093,363 remain available for offer and sale under the ATM Program.

In connection with the filing of the Prospectus Supplement, the Company is filing as Exhibit 5.1 hereto the opinion of its counsel, Goodwin Procter LLP.

(d) Exhibits

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SIGNATURE

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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