Revenue Ruling 2020-28 provides the interest rates for the first quarter of 2021. The rates for interest determined under Section 6621 of the code for the calendar quarter beginning January 1, 2021, 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 2020-28 will be in IRB: 2020-52, dated December 21, 2020.