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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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): December 31, 2012

Belden Inc.

(EXACT NAME OF REGISTRANT AS SPECIFIED IN CHARTER)

7733 Forsyth Boulevard, Suite 800

St. Louis, Missouri 63105

(Address of Principal Executive Offices, including Zip Code)

(314) 854-8000

(Registrant’s telephone number, including area code)

n/a

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

Check the appropriate box below if this Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

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On December 31, 2012, Belden Inc. (the “Company”) entered into an Amendment No. 3 to Credit Agreement (the “Credit Agreement”) with the financial institutions listed on the signature pages thereof and JPMorgan Chase Bank, N.A., as Administrative Agent (the “Amendment”). The Amendment corrected a technical limitation in the Credit Agreement in order to allow the Company to hold an intercompany note from one of its European subsidiaries.

A copy of the Amendment is filed as Exhibit 10.1 hereto. The foregoing description of the Amendment does not purport to be complete, and is qualified in its entirety by reference to the full text to the Amendment, which is incorporated by reference herein. The representations and warranties contained in the Amendment and the related Credit Agreement were made only for purposes thereof and as of specific dates; were solely for the benefit of the parties to the Amendment and the related Credit Agreement; and may be subject to standards of materiality applicable to the contracting parties that differ from those applicable to investors. Investors should not rely on the representations and warranties or any description thereof as characterizations of the actual state of facts or condition of the Company. Moreover, information concerning the subject matter of the representations and warranties may change after the date of the Amendment and the related Credit Agreement, which subsequent information may or may not be fully reflected in public disclosures by the Company.

(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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