31 C.F.R. § 901.11 Use and disclosure of mailing addresses.
Title 31 - Money and Finance: Treasury
(a) When attempting to locate a debtor in order to collect or compromise a debt under parts 900–904 of this chapter or other authority, agencies may send a request to the Secretary (or designee) to obtain a debtor's mailing address from the records of the Internal Revenue Service. (b) Agencies are authorized to use mailing addresses obtained under paragraph (a) of this section to enforce collection of a delinquent debt and may disclose such mailing addresses to other agencies and to collection agencies for collection purposes.
Title 31: Money and Finance: Treasury
PART 901—STANDARDS FOR THE ADMINISTRATIVE COLLECTION OF CLAIMS
§ 901.11 Use and disclosure of mailing addresses.

