The IRS has announced that the interest rates applicable to overpayments and underpayments of federal taxes are the same in the fourth quarter of 2020 as they were in the third quarter of 2020 (Rev. Rul. 2020-18). The rates are:
Retirement plan set up by a self-employed person, providing tax-deductible contributions, tax-free income accumulations until withdrawal, and favorable averaging for qualifying lump-sum distributions.