Rev. Rul. 2024-25, page 1181.

Interest rates: underpayments and overpayments. The rates for interest determined under Section 6621 of the code for the calendar quarter beginning January 1, 2025, will be 7 percent for overpayments (6 percent in the case of a corporation), 7 percent for underpayments, and 9 percent for large corporate underpayments. The rate of interest paid on the portion of a corporate overpayment exceeding $10,000 will be 4.5 percent.