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:
A retirement account to which up to $4,000 (or $5,000 if you are 50 or over) may be contributed for 2007, but deductions for the contribution are restricted if you are covered by a company retirement plan. Earnings accumulate tax free.