The following quarterly interest rates for overpayments and underpayments of taxes will be effective for the calendar quarter beginning October 1, 2001:
- Interest will remain at 7 percent for overpayments
- Interest will remain at 6 percent for corporate overpayments
- The overpayment rate for the portion of a corporate overpayment exceeding $10,000 will be 4.5 percent
- Interest will remain at 7% for underpayments
- Interest will remain at 9% for large corporate underpayments
The interest rates were announced in Rev. Rul. 2001-47, which contains tables of all interest rates since 1975.