<PAGE>
Exhibit 15
July 26, 2000
PC Connection, Inc. and Subsidiaries
Merrimack, New Hampshire
We have made a review, in accordance with standards established by the American
Institute of Certified Public Accountants, of the unaudited interim financial
information of PC Connection, Inc. and subsidiaries for the periods ended June
30, 2000 and 1999, as indicated in our report dated July 18, 2000; because we
did not perform an audit, we expressed no opinion on that information.
We are aware that our report referred to above, which is included in your
Quarterly Report on Form 10-Q for the quarter ended June 30, 2000, is
incorporated by reference in Registration Statement Nos. 333-69981, 333-50847,
333-50845, 333-83943 and 333-40172 of PC Connection, Inc. on Form S-8.
We also are aware that the aforementioned report, pursuant to Rule 436(c) under
the Securities Act of 1933, is not considered a part of the Registration
Statement prepared or certified by an accountant or a report prepared or
certified by an accountant within the meaning of Sections 7 and 11 of that Act.
DELOITTE & TOUCHE LLP
Boston, Massachusetts
