12 C.F.R. § 608.821 – Collection by offset.

(a) Collection of a debt by administrative [or salary] offset shall be accomplished in accordance with the provisions of these regulations, of 4 CFR 102.3, and 5 CFR part 550, subpart K. It is not necessary for the debt to be reduced to judgment or to be undisputed for offset to be used.
(b) The Chairman, or designee of the Chairman, may determine that it is feasible to collect a debt to the United States by offset against funds payable to the debtor.
(c) The feasibility of collecting a debt by offset will be determined on a case-by-case basis. This determination shall be made by considering all relevant factors, including the following:
1. (1) The degree to which the offset can be accomplished in accordance with law. This determination should take into consideration relevant statutory, regulatory, and contractual requirements;
2. (2) The degree to which the FCA is certain that its determination of the existence and amount of the debt is correct;
3. (3) The practicality of collecting the debt by offset. The cost, in time and money, of collecting the debt by offset and the amount of money which can reasonably be expected to be recovered through offset will be relevant to this determination; and
4. (4) Whether the use of offset will substantially interfere with or defeat the purpose of a program authorizing payments against which the offset is contemplated. For example, under a grant program in which payments are made in advance of the grantee's performance, the imposition of offset against such a payment may be inappropriate.
(d) The collection of a debt by offset may not be feasible when there are circumstances which would indicate that the likelihood of collection by offset is less than probable.
(e) The offset will be effected 31 days after the debtor receives a Notice of Intent to Collect by Administrative Offset (or Notice of Intent to Collect by Salary Offset if the offset is a salary offset), or upon the expiration of a stay of offset, unless the FCA determines under § 608.824 that immediate action is necessary.
(f) If the debtor owes more than one debt, amounts recovered through offset may be applied to them in any order. Applicable statutes of limitation would be considered before applying the amounts recovered to any debts owed.