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): December 14, 2010

VONAGE HOLDINGS CORP.

(Exact Name of Registrant as Specified in Charter)

Registrant’s telephone number, including area code: (732) 528-2600

(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 December 14, 2010, Vonage Holdings Corp. (the “Company”), in connection with the successful completion of its previously announced refinancing, entered into a credit agreement (the “Credit Facility”) among the Company, Vonage America Inc., Bank of America, N.A. as administrative agent and Bank of America, N.A., as lender. The Credit Facility consists of a $200 million senior secured term loan, which replaced the Company’s first, second and third lien debt totaling $194 million. Banc of America Securities LLC acted as lead arranger and bookrunning manager for the Credit Facility. Deutsche Bank Securities Inc. and Citigroup Global Markets Inc. acted as co-arrangers for the Credit Facility.

The co-borrowers under the Credit Facility are the Company and Vonage America Inc., its wholly owned subsidiary. Obligations under the Credit Facility are guaranteed, fully and unconditionally, by the Company’s other U.S. subsidiaries and are secured by substantially all of the assets of each borrower and each of the guarantors.

Use of Proceeds

The Company used the net proceeds of the Credit Facility, plus cash on hand, to (i) exercise its existing right to retire debt under its senior secured first lien credit facility for 100% of the contractual make-whole price, (ii) retire debt under its senior secured second lien credit facility at a more than 25% discount to the contractual make-whole price, and (iii) cause the conversion of all outstanding third lien convertible notes into 8.3 million shares of the Company’s common stock.

The remaining charges associated with the retirement of the first, second and third lien debt, totaling approximately $60 million, will be recorded in the fourth quarter.

Credit Facility

The following description summarizes the material terms of the new Credit Facility.

The loans under the Credit Facility mature in December 2015. The loans under the Credit Facility were issued at an original issuance discount of $6 million. Principal amounts under the Credit Facility are repayable in quarterly installments of approximately $5 million per quarter, with the balance due in December 2015.

Amounts under the Credit Facility, at the Company’s option, will bear interest at:

The LIBOR rate for term loans under the Credit Facility will be subject to a floor of 1.75%.

The Company may prepay the Credit Facility at its option at any time without premium or penalty except breakage costs and, if prepaid within the first year with proceeds of indebtedness, a prepayment fee of 1.00% of the amount repaid. The Credit Facility is subject to mandatory prepayments in amounts equal to:

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Subject to certain restrictions and exceptions, the Credit Facility permits the Company to obtain one or more incremental term loan and/or revolving credit facilities in an aggregate principal amount of up to $40 million pursuant to documentation reasonably satisfactory to the administrative agent, without the consent of the existing lenders under the Credit Facility.

The Credit Facility includes customary representations and warranties and affirmative covenants of the borrowers. In addition, the Credit Facility contains customary negative covenants, including, among other things, restrictions on the borrowers’ and the guarantors’ ability to consolidate or merge, create liens, incur additional indebtedness, dispose of assets, consummate acquisitions, make investments and pay dividends and other distributions. The Company must also comply with the following financial covenants:

The Credit Facility contains customary events of default that may permit acceleration of the debt under the Credit Facility. During the continuance of a payment or bankruptcy event of default, or upon any other event of default upon request of lenders holding advances representing more than 50% of the aggregate principal amount of advances outstanding under the Credit Facility, interest will accrue at a default interest rate of 2% above the interest rate which would otherwise be applicable.

Additional Information

An affiliate of Jeffrey Citron, the chairman of the Company’s board of directors and one of the Company’s principal stockholders, is a lender under the Credit Facility. Because of the interests of Mr. Citron, the Credit Facility and the transactions contemplated thereby were approved by the Company’s board of directors (with Mr. Citron abstaining) upon the recommendation of a special committee of disinterested directors.

The foregoing description of the Credit Facility is qualified in its entirety by reference to the full text of the Credit Facility, a copy of which is attached hereto as Exhibit 10.1 and is incorporated herein by reference.

The information in Item 1.01 of this report is incorporated by reference.

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On December 14, 2010, the Company issued a press release announcing the execution of the Credit Facility. The press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

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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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EXHIBIT INDEX

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