IRS Rev. Rul.: Interest Rates for Tax Overpayments, Underpayments for Q1 2026 (IRC §6621)

The IRS issued a revenue ruling that establishes the quarterly interest rates for tax overpayments and underpayments effective from Jan. 1 to March 31, 2026. The ruling sets the overpayment rate at 7 percent for individuals and 6 percent for corporations, while the underpayment rate is 7 percent for all taxpayers. Corporate overpayments exceeding $10,000 bear interest at 4.5 percent, and large corporate underpayments are subject to a 9 percent rate. The ruling also sets the interest rate for deposits under I.R.C. §6603 at 4 percent and confirms that these rates apply to estimated tax underpayments as outlined in I.R.C. ...