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): September 17, 2014

Marchex, Inc.

(Exact name of Registrant as Specified in its Charter)

520 Pike Street

Suite 2000

Seattle, Washington 98101

(Address of Principal Executive Offices)

(206) 331-3300

(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):

Updated Call Driven Financial Guidance.

On September 18, 2014, Marchex, Inc. (“Marchex”) is issuing a press release and holding a conference call regarding updated call-driven financial guidance for the third quarter ending September 30, 2014 and for the full year ending December 31, 2014 (the “Press Release”). The full text of the Press Release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The information in this Item 7.01 (including Exhibit 99.1) is being furnished and shall not be deemed “filed” for the purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities of that section. Such information shall not be incorporated by reference into any registration statement or other document pursuant to the Securities Act of 1933 or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Marchex is referencing non-GAAP financial information in the Press Release and on the conference call. Reconciliations of these non-GAAP financial measures to the comparable GAAP financial measures are included in publicly-available documents filed with the Securities and Exchange Commission (the “SEC”) and posted on Marchex’s website, www.marchex.com, under Investor Relations. Disclosures regarding definitions of these financial measures used by Marchex and why Marchex’s management believes these financial measures provide useful information to investors are also included in these documents.

Safe Harbor Disclosure

This Current Report on Form 8-K contains forward-looking statements within the meaning of the Securities Act and of the Exchange Act that involve substantial risks and uncertainties. All statements, other than statements of historical facts, included in this Current Report on Form 8-K regarding our strategy, future operations, future financial position, future revenues, other financial guidance, projected costs, prospects, plans and objectives of management are forward-looking statements.

Actual results could differ materially from those projected in our forward-looking statements due to risks, uncertainties and other factors. Important factors that could affect actual results are discussed in Marchex’s filings with the SEC including but not limited to the risks discussed under Item 1A “Risk Factors” in Marchex’s Annual Report on Form 10-K for the year ended December 31, 2013, as well as our other SEC filings. Marchex undertakes no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

(d) Exhibits.

SIGNATURES

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

EXHIBIT INDEX