Tax overpayment and underpayment interest rates will remain unchanged for the first quarter of 2021.
December 9, 2020
For noncorporate taxpayers, the rate for both underpayments and overpayments for the quarter starting Jan. 1 will be 3%. The 3% rate also applies to estimated tax underpayments for the first quarter of 2021. For corporations, the overpayment rate will be 2%, with a 0.5% rate applicable to overpayments exceeding $10,000. The underpayment rate for corporations will be 3%, except for large corporate underpayments, which will be 5%. (IRS Rev. Rul. 2020-28)