Treasury Regulations (26 C.F.R.)

26 CFR § 20.6601-1 — Interest on underpayment, nonpayment, or extensions of time for payment, of tax.

§ 20.6601-1 Interest on underpayment, nonpayment, or extensions of time for payment, of tax.

For regulations concerning interest on underpayments, etc., see § 301.6601-1 of this chapter (Regulations on Procedure and Administration).

Last amended: 2026-04-13