SECTION 1. PURPOSE

This revenue procedure provides guidance regarding the application of § 6621(d) of the Internal Revenue Code to interest accruing on or after October 1, 1998. Section 6621(d) was enacted by § 3301 of the Internal Revenue Service Restructuring and Reform Act of 1998 (RRA), Pub. L. No. 105–206, 112 Stat. 741, and was amended by § 4002(d) of the Tax and Trade Relief Extension Act of 1998, Pub. L. No. 105–277, 112 Stat. 2681. Section 6621(d) provides for a net interest rate of zero to the extent of overlapping tax underpayments and tax overpayments, and generally applies to interest for periods beginning after July 22, 1998 (i.e., interest accruing on or after October 1, 1998). The net interest rate of zero in § 6621(d) also applies to interest for periods beginning before July 22, 1998 (i.e., interest accruing before October 1, 1998), provided certain conditions are met. Rev. Proc. 99–43, 1999–47 I.R.B. 579, which modifies and supersedes Rev. Proc. 99–19, 1999–13 I.R.B. 10, provides guidance on the conditions applicable to requests for the application of a net interest rate of zero to interest accruing before October 1, 1998. Section 3.02(1) of Rev. Proc. 99–43 states that the Service intends to provide further guidance for interest accruing for periods on or after October 1, 1998. This revenue procedure provides guidance on the application of § 6621(d) for interest accruing on or after October 1, 1998.