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): January 25, 2013

WEX INC.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (207) 773-8171

(Former Name or Former Address, if Changed Since Last Report)

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):

On January 25, 2013, WEX Inc., a Delaware corporation (the “Company”), announced the pricing of its previously announced private offering of 4.75% senior notes due 2023 (the “Notes”). The aggregate principal amount of the Notes is $400 million. The Notes will pay interest on a semiannual basis. The offering of the Notes is expected to close on January 30, 2013.

The Notes are being sold in a private placement to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”), and to non-U.S. persons outside the United States under Regulation S under the Securities Act. The Notes have not been registered under the Securities Act, and may not be offered or sold in the United States absent registration or an applicable exemption from, or in a transaction not subject to, the registration requirements of the Securities Act and other applicable securities laws.

A copy of the press release announcing the pricing of the Notes is attached to this Current Report on Form 8-K as Exhibit 99.1 and is incorporated herein by reference.

See Exhibit Index attached hereto.

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.

EXHIBIT INDEX