Treas. Reg. § 41.6109-1 Identifying numbers.

eCFR as of 2026-10-19 · Interprets § 6109

Every person required under § 41.6011(a)-1 to make a return must provide the identifying number required by the instructions to the form on which the return is made.

[T.D. 8879, 65 FR 17155, Mar. 31, 2000]