IRS Interest Rates Unchanged for Q4 2021

Despite indications of increased inflation, the interest rates on overpayments and underpayments are unchanged from the second quarter of 2021 (Rev Rul. 2021-17). The rates for the fourth quarter of 2021 beginning on October 1 are:

• Noncorporate overpayments and underpayments: 3%
• Corporate overpayments: 2% generally, but 0.5% for corporate overpayments exceeding $10,000
• Corporate underpayments: 3% generally, but 5% for large corporate underpayments