Revenue Ruling 2021-24 provides interest rates for underpayments and overpayments. The rates for interest determined under Section 6621 of the code for the calendar quarter beginning January 1, 2022, will be 3 percent for overpayments (2 percent in the case of a corporation), 3 percent for underpayments, and 5 percent for large corporate underpayments. The rate of interest paid on the portion of a corporate overpayment exceeding $10,000 will be 0.5 percent.

Revenue Ruling 2021-24 will be in IRB: IRB 2021-50, dated December 13, 2021.