On 21 February 2024, the US Internal Revenue Service (IRS) declared the interest rates for overpayments and underpayments. As per the announcement, the interest rates will remain the same for the calendar quarter beginning 1 April 2024.

For individuals, the rate for overpayments and underpayments will be 8% per year, compounded daily. Here’s a complete list of the new rates:

  • 8% for overpayments (payments made in excess of the amount owed), 7% for corporations.
  • 5.5% for the portion of a corporate overpayment exceeding $10,000.
  • 8% for underpayments (taxes owed but not fully paid).
  • 10% for large corporate underpayments.

Under the Internal Revenue Code, the rate of interest is determined on a quarterly basis. For taxpayers other than corporations, the overpayment and underpayment rate is the federal short-term rate plus three percentage points.

Generally, in the case of a corporation, the underpayment rate is the federal short-term rate plus three percentage points, and the overpayment rate is the federal short-term rate plus two percentage points. The rate for large corporate underpayments is the federal short-term rate plus five percentage points. The rate on the portion of a corporate overpayment of tax exceeding $10,000 for a taxable period is the federal short-term rate plus one-half (0.5) of a percentage point.

The newly announced interest rates are computed from the federal short-term rate determined during January 2024.

The new interest rates and past rates will be published in Internal Revenue Bulletin 2024-10 Revenue Ruling 2024-6, of 4 March 2023.