§ StatuteRates

IRS Large Corporate Underpayment Rate (LCU)

United States  The higher rate on large corporate tax underpayments.

Current rate
9% per year, effective July 1, 2026
Published value

The large corporate underpayment rate ("LCU") is an elevated rate that applies to sizable corporate underpayments. Under §6621(c) it equals the federal short-term rate plus 5 percentage points and is reset each quarter — two points above the ordinary underpayment rate.

→ Calculate interest at this rate

Effective-date history

39 data points on record. Full history in the JSON API.
Effective dateRateBasis
July 1, 2026 9% Published
April 1, 2026 8% Published
January 1, 2026 9% Published
October 1, 2025 9% Published
July 1, 2025 9% Published
April 1, 2025 9% Published
January 1, 2025 9% Published
October 1, 2024 10% Published
July 1, 2024 10% Published
April 1, 2024 10% Published
January 1, 2024 10% Published
October 1, 2023 10% Published
July 1, 2023 9% Published
April 1, 2023 9% Published
January 1, 2023 9% Published
October 1, 2022 8% Published
July 1, 2022 7% Published
April 1, 2022 6% Published
January 1, 2022 5% Published
October 1, 2021 5% Published
July 1, 2021 5% Published
April 1, 2021 5% Published
January 1, 2021 5% Published
October 1, 2020 5% Published
July 1, 2020 5% Published
April 1, 2020 7% Published
January 1, 2020 7% Published
October 1, 2019 7% Published
July 1, 2019 7% Published
April 1, 2019 8% Published
January 1, 2019 8% Published
October 1, 2018 7% Published
July 1, 2018 7% Published
April 1, 2018 7% Published
January 1, 2018 6% Published
October 1, 2017 6% Published
July 1, 2017 6% Published
April 1, 2017 6% Published
January 1, 2017 6% Published

Source & provenance

Latest value retrieved July 10, 2026 (02:55 UTC) from the official source:
https://www.irs.gov/payments/quarterly-interest-rates

Reference data only — not legal, tax, or financial advice. Always confirm the controlling value against the official source and, where applicable, the governing statute or court before relying on it.