The IRS interest rates on overpayments and underpayments for the fourth quarter of 2022 are one percentage point higher than in the third quarter (Rev. Rul. 2022-15). This is the third interest rate increase this year. The rates beginning October 1, 2022, are:
Interest deemed earned on seller-financed sales or low-interest loans, where the parties’ stated interest rate is below the applicable IRS federal rate.