Permanent increase to penalty interest rates
The new tax year saw a change to the way interest on late paid taxes is calculated. What’s changed and what are the new charges?

Prior to 2025/26, interest was charged at the Bank of England base rate plus 2.5% on most underpaid taxes. In a push for unpaid tax bills to be settled, it was announced at the 2024 Autumn Budget that this would change to the base rate plus 4% from 6 April 2025. The government says the rate of late payment interest encourages prompt payment and ensures fairness for those who pay their tax on time.
From 6 April 2025 the following rates apply:
- Late corporation tax paid quarterly - 7%
- Late payment interest on other taxes - 8.5%
There is no corresponding change to the way repayment interest rates are calculated, i.e. the base rate minus 1%, with a lower limit of 0.5%.
Related Topics
-
How much will you save with reduced scale charges?
HMRC has reduced the VAT fuel scale charge by nearly 6% for company-provided cars. When does the new reduced rate take effect and how do you make the calculations?
-
Avoid the trading allowance trap
In late 2024 you became self-employed. You’re now completing your tax return for 2024/25 and will claim the trading allowance instead of a tax deduction for business expenses. Could this impact your NI record and state pension entitlement?
-
Time off for fertility treatment?
A survey by Fertility Matters at Work has revealed that more than one-third of employees undergoing fertility treatment have resigned or are considering resigning because of the physical and emotional toll. Is there a right to time off for fertility treatment?