Taxpayer Assistance - Confidentiality of Taxpayer Information

All tax or financial information you provide to the Department, either on returns or through Department investigation, is held in strict confidence by law. The information may be disclosed to the United States Internal Revenue Service, agencies responsible for the administration of taxes in other states, in accordance with compacts for the exchange of information, and as otherwise authorized by New Hampshire RSA 21-J:14.
The disclosure of a taxpayer's Social Security Number (SSN) or Federal Employer Identification Number (FEIN) is mandatory under NH Code of Administrative Rule Rev 203.01 and authorized under RSA 21-J:27-a. This information is required for the purpose of administering the tax laws of this state and authorized by 42 U.S.C.S. § 405(c)(2)(C)(i).

It is mandatory to furnish SSNs or FEINs when an appeal is filed with the Department. The failure to provide SSNs or FEINs may result in a rejection of an appeal and the loss of the taxpayer's right of appeal pursuant to RSA 21-J:28-b.