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): March 7, 2013

ATLANTIC POWER CORPORATION

(Exact name of registrant as specified in its charter)

British Columbia, Canada |  | 001-34691 |  | 55-0886410
(State or other jurisdiction of incorporation or organization) |  | (Commission File Number) |  | (IRS Employer Identification No.)

One Federal Street, Floor 30 Boston, MA |  | 02110
(Address of principal executive offices) |  | (Zip Code)

(617) 977-2400

(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:

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

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

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

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

Item 7.01. Regulation FD Disclosure.

On March 7, 2013, Atlantic Power Corporation (the “Company”) posted to its website materials entitled “Q4 and YE 2012 Investor Presentation, March 2013” for a presentation by Barry E. Welch, the Company’s President and Chief Executive Officer, to be made at the Morgan Stanley Utilities Conference on March 7, 2013 and March 8, 2013, which materials are attached to this Current Report on Form 8-K as Exhibit 99.1.

Information on the Company’s website is not incorporated by reference in the Current Report on Form 8-K. The information in this Current Report on Form 8-K and the exhibit attached shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall they be deemed incorporated by reference in any registration statement or other filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, unless the Company expressly states that such information is to be considered “filed” under the Exchange Act or incorporates such information by specific reference in a Securities Act or Exchange Act filing.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

Exhibit |  |
Number |  | Description
99.1 |  | Q4 and YE 2012 Investor Presentation, March 2013

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.

| Atlantic Power Corporation
Dated: March 7, 2013 | By: | /s/ Terrence Ronan
|  | Name: Terrence Ronan
|  | Title: Chief Financial Officer

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EXHIBIT INDEX

Exhibit |  |
Number |  | Description
99.1 |  | Q4 and YE 2012 Investor Presentation, March 2013

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