Killer Tax Brief

Week 8, 2026 Rev. Rul. 2026-5 — Updates quarterly interest rates on tax overpayments and underpayments to 6% (5% for corporations) effective April 1, 2026, based on 3% federal short-term rate.

Week 8, 2026 Rev. Rul. 2026-5 — IRS sets quarterly interest rates for tax overpayments and underpayments at 6% for individuals and corporations for the second quarter of 2026, with special rates for large corporate underpayments (8%) and corporate overpayments exceeding $10,000 (3.5%).