IRS Underpayment Interest Rate (§6621)
United States What the IRS charges on unpaid federal tax.
Published value
IRS Underpayment Interest Rate (§6621) at a glance
- Current rate
- 7% per year
- Effective date
- July 1, 2026
- Controlling authority
- 26 U.S.C. §6621
- Rate basis
- Published value
- Source checked
- August 25, 2026
- Recorded history
- 39 data points
The IRS underpayment rate is the interest the IRS charges individuals and businesses on tax they paid late or underpaid. Under Internal Revenue Code §6621 it equals the federal short-term rate plus 3 percentage points, and it is reset every calendar quarter — so a figure that was right last quarter is often wrong today. This page tracks the published value each quarter with its effective date.
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Effective-date history
| Effective date | Rate | Basis |
|---|---|---|
| July 1, 2026 | 7% | Published |
| April 1, 2026 | 6% | Published |
| January 1, 2026 | 7% | Published |
| October 1, 2025 | 7% | Published |
| July 1, 2025 | 7% | Published |
| April 1, 2025 | 7% | Published |
| January 1, 2025 | 7% | Published |
| October 1, 2024 | 8% | Published |
| July 1, 2024 | 8% | Published |
| April 1, 2024 | 8% | Published |
| January 1, 2024 | 8% | Published |
| October 1, 2023 | 8% | Published |
| July 1, 2023 | 7% | Published |
| April 1, 2023 | 7% | Published |
| January 1, 2023 | 7% | Published |
| October 1, 2022 | 6% | Published |
| July 1, 2022 | 5% | Published |
| April 1, 2022 | 4% | Published |
| January 1, 2022 | 3% | Published |
| October 1, 2021 | 3% | Published |
| July 1, 2021 | 3% | Published |
| April 1, 2021 | 3% | Published |
| January 1, 2021 | 3% | Published |
| October 1, 2020 | 3% | Published |
| July 1, 2020 | 3% | Published |
| April 1, 2020 | 5% | Published |
| January 1, 2020 | 5% | Published |
| October 1, 2019 | 5% | Published |
| July 1, 2019 | 5% | Published |
| April 1, 2019 | 6% | Published |
| January 1, 2019 | 6% | Published |
| October 1, 2018 | 5% | Published |
| July 1, 2018 | 5% | Published |
| April 1, 2018 | 5% | Published |
| January 1, 2018 | 4% | Published |
| October 1, 2017 | 4% | Published |
| July 1, 2017 | 4% | Published |
| April 1, 2017 | 4% | Published |
| January 1, 2017 | 4% | Published |
Source & provenance
Observation recorded August 25, 2026 (02:50 UTC) from the cited source (U.S. Internal Revenue Service):
https://www.irs.gov/payments/quarterly-interest-rates
Cite this page
StatuteRates. “IRS Underpayment Interest Rate (§6621).” StatuteRates.com. Accessed today. https://statuterates.com/rates/irs-underpayment/ Rate recorded under 26 U.S.C. §6621, effective July 1, 2026.