Late payment interest calculator (UK)
A business customer hasn't paid your invoice on time? UK law lets you claim statutory interest and a fixed sum for recovery costs. Enter the details to see what you could add.
How it's worked out
- Statutory interest for business-to-business debts is 8% plus the Bank of England base rate a year. Daily interest is the amount × rate ÷ 365, multiplied by the number of days late.
- The base rate was 3.75% when checked on 16 October 2026. Strictly, the rate that applies is the base rate on 30 June (for debts that become late from 1 July) or 31 December (from 1 January), so change the box above if that differs.
- Fixed compensation per late payment: £40 for debts up to £999.99, £70 for £1,000 to £9,999.99, and £100 for £10,000 or more. You can charge it once per invoice, on top of interest.
- You can't claim statutory interest if your contract sets a different interest rate. It doesn't apply to private customers (consumers).
- If no payment date was agreed, a payment is late 30 days after the customer gets your invoice, or after you deliver (if that's later).
- If you decide to add interest, GOV.UK says to send a new invoice for it.
Sources: GOV.UK: when a payment becomes late, interest on late commercial payments, claiming debt recovery costs and the Bank of England base rate.
Track every invoice in one sheet
The UK Freelance Invoice & Late Payment Tracker logs every invoice, works out due dates and status, flags what's overdue, prints invoices, and calculates this interest and compensation automatically, with ready-to-copy reminder messages. It's coming to the Tidy Sheets shop soon.
Visit the shopPlanning for your tax bill too? Try the free tax set-aside calculator. New to chasing invoices? Read the late paying clients guide.