How refund interest works

Refund interest compensates taxpayers when the government holds an overpayment longer than federal law allows. The IRS computes interest automatically — you do not need to request it — and includes it with your refund when applicable. (See the IRS overview on refund interest for current rules and rates: https://www.irs.gov/newsroom/refund-interest.)

Key rules and timing

  • Start date: Interest accrues from the later of (a) the original due date of the return (without regard to extensions) or (b) the date you paid the tax overpayment.
  • End date: Interest runs until the date the IRS actually issues the refund.
  • Rate and compounding: Interest rates are set quarterly under federal tax law (IRC §6621), equal to the federal short-term rate plus a statutory add-on, and are compounded daily.
  • Automatic payment: If you are due interest, the IRS adds it to your refund; you do not need to file a separate claim.

How the IRS calculates the dollar amount (simple example)

The IRS compounds daily for precision, but you can estimate interest with an annual-rate formula. Example: a $1,000 overpayment, IRS annual interest rate 5%, refund issued 9 months (0.75 year) later.
Estimated interest = $1,000 × 5% × 0.75 = $37.50 (the IRS daily-compounded figure will be very close to this).

Who qualifies and common exceptions

  • Eligible: Any taxpayer (individual or business) who overpays federal tax and receives a refund after the statutory start date is generally entitled to interest.
  • Reported refunds: Interest applies regardless of payment method (direct deposit, check) and is paid even when the refund results from filing an amended return, subject to timing rules.
  • Taxable: Refund interest is taxable income and usually reported by the IRS on Form 1099-INT (see Form 1099-INT instructions: https://www.irs.gov/forms-pubs/about-form-1099-int).

What to do if you think interest is missing

  1. Check the refund amount and any IRS offset notices (sometimes interest is reduced if your refund was offset to pay a federal or state debt). See our guide on refund offsets for options and prevention: How Tax Refund Offsets Work and Your Options to Prevent Them.
  2. Track processing delays that might affect timing and interest using the IRS “Where’s My Refund?” tool and read common causes in our article: What Can Delay a Tax Refund and How to Avoid Those Delays.
  3. If a refund (or its interest) is missing, follow the IRS trace procedures or file a claim; our step-by-step page on tracing missing refunds can help: Claiming a Missing Refund: Steps to Trace and Recover a Lost Tax Refund.

Practical tips

  • File electronically and choose direct deposit to speed receipt of refunds and interest payments.
  • Keep proof of payments and filed returns so you can document the overpayment date if you must question the IRS’s calculation.
  • Expect the IRS to issue Form 1099-INT for reportable interest; include it on the following year’s tax return.

Common misconceptions

  • “I must request refund interest.” No — the IRS calculates and pays it automatically when due.
  • “Refund interest is tax-free.” No — it is taxable and typically reported on Form 1099-INT.

Sources and authority

Professional disclaimer: This article is educational and not personalized tax advice. For guidance tailored to your situation, consult a CPA or tax attorney.