[Vonage Letterhead]

In addition, you will be granted an option under Vonage Holding Corp.’s 2006 Incentive Plan (the “Incentive Plan”) to purchase 1,000,000 shares of Vonage Holding Corp.’s common stock, pursuant to a stock option agreement (the “Stock Option Agreement”) substantially in the form of the Company’s form of stock option agreement in accordance with the Incentive Plan (the number of shares and exercise price are subject to adjustment based on subsequent stock splits, reverse stock splits, other adjustments, or recapitalizations, as provided in the Incentive Plan). Subject to your continued employment on the applicable vesting dates, the options will vest and become exercisable as to 1/4^th of the shares on each of the first, second, third and fourth anniversaries of the date of the award, which will be September 4, 2012. The exercise price will be the closing price of a share of Company stock on the date of the award. The stock option grant will be governed by and subject to the terms of the Incentive Plan and the Stock Option Agreement and in the event of a conflict between this paragraph and the Incentive Plan and Stock Option Agreement, the terms of the Incentive Plan and Stock Option Agreement shall control.

In addition, in the event your employment is terminated by the Company without Cause or by you with Good Reason, each as defined below, you will be entitled to (i) severance pay equal to twelve (12) months of your then-current base salary, less applicable withholding, which will be paid by the Company during its regular payroll cycle over the twelve (12) month period following the date of your employment termination; provided that the first payment shall be made on the sixtieth (60th) day after your termination of employment, and such first payment shall include payment of any amounts that otherwise would be due prior thereto, (ii) (x) if such termination of employment occurs in calendar year 2012, a pro rata portion of the Guaranteed Bonus, or (y) if such termination of employment occurs thereafter, a pro-rata portion of your TBO for the year of termination based on the Company’s actual performance for such year, in either case, less applicable withholding and payable in the year following the year in which your employment terminates at such time as annual bonuses in respect of such year are normally paid to other senior executives of the Company; provided, however that the Company shall not be required to make the payments set forth in this paragraph 6 unless you execute and deliver to the Company a Separation Agreement and General Release in a form reasonably acceptable to the Company in its sole discretion (the “Release”.) and such Release has become effective and irrevocable in its entirety within sixty (60) days of your termination of

employment. The Release shall not contain post-employment obligations more restrictive then those post-employment obligations set forth in the Non-Compete Agreement. For the avoidance of doubt, any severance payments payable pursuant to this paragraph 6 shall be forfeited unless an effective Release has been received by the Company and has become irrevocable no later then sixty (60) days following your termination of employment. During the Severance period, you shall continue coverage in the Company’s medical and dental health care plans at your active employee rate; provided, that you are and remain eligible for continuation coverage under the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended; provided, further, that such continuation coverage shall immediately cease if you become eligible to receive group health coverage from another employer.

“Cause” means (i) material failure to perform your employment duties (not as consequences of any illness, accident or other disability, (ii) continued, willful failure to carry out any reasonable lawful direction of the Company, (iii) diverting or usurping a corporate opportunity of the Company (Iv) fraud, willful malfeasance, gross negligence or recklessness in the performance of employment duties, (v) willful failure to comply with any of the material terms of this Offer Letter (vi) other serious, willful misconduct which causes material injury to the Company or its reputation, including but not limited to, willful or gross misconduct toward any of the Company’s other employees, (vii) conviction of, or pleas of nolo contendre to, a felony or a crime involving moral turpitude, and (viii) violation of any written Company policies or procedures; provided, however that no event or condition describe in clauses (i), (ii) or (v) shall constitute Cause unless (x) the Company give you written notice of its intension to terminate your employment for Cause and the grounds for such termination and (y) such grounds for termination (if susceptible to correction) are not corrected by you within 15 day of your receipt of such notice. If you do not correct the grounds for termination during such 15-day cure period, your termination of employment for Cause shall become effective on the first business day following the end of the cure period. Unless otherwise advised by the Company, you will be expected to perform services for the Company during the cure period.

“Good Reason” means: (i) a decrease in your base salary; (ii) a material diminution of your authorities, duties or responsibilities, (iii) a failure of the Company to pay compensation due and payable to you in connection with your employment or (iv) relocation by the Company of your principal place of employment to a location that results in your commuting distance being at least 30 miles greater than your commuting distance on the date you commence employment; provided, however that no event or condition described in clauses (i) through (iv) shall constitute Good

Reason unless (x) you give the Company’s most senior Human Resources employee written notice of your intention to terminate your employment for Good Reason and the grounds for such termination within 45 days after the occurrence of the event giving rise to the “Good Reason” termination and (y) such grounds for termination (if susceptible to correction) are not corrected by the Company within 30 days of its receipt of such notice (or, in the event that such grounds cannot be corrected within such 30-day period, the Company has not taken all reasonable steps within such 30 day period to correct such grounds as promptly as practicable thereafter). If the Company does not correct the grounds for termination during such 30 day cure period (or take all reasonable steps within such 30 days period to correct such grounds as promptly as practicable thereafter), your termination of employment for “Good Reason” shall become effective on the first business day following the end of the cure period.

Unless otherwise advised by the Company, you will be expected to perform services for the Company during the cure period.