Exhibit 15

May 9, 2006

Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549

     RE: Tollgrade Communications, Inc.

1)	Form S-8 (Registration No. 333-4290, 333-65502, 333-83007 and 333-95965) 1995 Long-Term Incentive Plan and Individual Stock Options Granted to Certain Directors and Employees Prior to the Adoption of the Plan
2)	Form S-8 (Registration No. 333-52907, 333-55470 and 333-096969) 1998 Employee Incentive Compensation Plan

Commissioners:

We are aware that our report dated May 4, 2006 on our review of interim financial information of Tollgrade Communications, Inc. for the three-month periods ended April 1, 2006 and March 26, 2005 and included in the Company’s quarterly report on Form 10-Q for the quarter ended April 1, 2006 is incorporated by reference in its Registration Statements referred to above.

Very truly yours

/s/ PricewaterhouseCoopers LLP

PricewaterhouseCoopers LLP

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