Tools
UK Late Payment Interest Calculator
Last updated: June 2026
This invoice is not yet overdue on the chosen date, so no statutory interest is shown. Set the “calculate up to” date after the due date.
Preview only, not legal advice. UK statutory late-payment interest and fixed compensation can depend on contract terms, debtor type, jurisdiction, and facts. Do not add this to reminders or legal notices automatically.
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How is UK statutory interest calculated?
Statutory interest on a qualifying commercial debt is simple interest at 8% plus the Bank of England base rate, charged per invoice from the day after the invoice was due until it is paid. Daily interest is the annual amount divided by 365, multiplied by the number of days overdue.
How much fixed compensation can you add?
On top of interest, you can usually claim a fixed sum per qualifying debt:
| Debt size | Fixed compensation |
|---|---|
| Up to £999.99 | £40 |
| £1,000 to £9,999.99 | £70 |
| £10,000 or more | £100 |
A worked example
A £10,000 invoice that is 60 days overdue, at 11.75%, accrues roughly £193.15 in interest, plus £100 fixed compensation — a total claim preview of about £10293.15. Your actual figure depends on your contract terms and the facts.
WolfX is software for evidence-backed invoice recovery workflows. WolfX is not a law firm, debt collection agency, court, or payment processor. This site provides general information, not legal advice.
Sources
- Late Payment of Commercial Debts (Interest) Act 1998 — legislation.gov.uk
- Late commercial payments: charging interest and debt recovery — GOV.UK
- Bank of England official Bank Rate — Bank of England
Frequently asked questions
What is the statutory rate?
8% plus the Bank of England base rate. With a base rate of 3.75% as of June 2026, that is 11.75% a year.
Can I claim interest and compensation per invoice?
Statutory interest and the fixed compensation sum generally apply per qualifying debt, subject to your contract terms and the facts. This is general information, not legal advice.
Do I need to warn the client first?
You do not have to warn a business customer before charging statutory interest, but it is common to state interest and compensation clearly in a reminder or Letter Before Action.
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