Late PaymentUK late payment interest calculator
A business client paid late? Work out the statutory interest and fixed compensation you can claim under the Late Payment of Commercial Debts (Interest) Act 1998 — currently 11.75% a year for debts that became late from 1 July 2026 to 31 December 2026.
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How it's worked out
- Rate: 8% plus the Bank of England base rate (the "reference rate") fixed for the half-year in which the payment became late.
- Daily interest: amount × rate ÷ 365. Multiply by the number of days late.
- Fixed compensation: £40 under £1,000, £70 from £1,000 to £9,999.99, £100 from £10,000 — once per invoice.
- When it's late: the day after the agreed due date, or 30 days after the invoice (or delivery, if later) if no date was agreed.
- Business clients only. The Act does not cover private individuals (consumers).
Read the plain-English guide →
Need the letters to send?
The UK Freelancer Contract Pack has a three-step late payment sequence — friendly reminder, firm reminder and a final notice citing the Late Payment of Commercial Debts (Interest) Act 1998 — plus a services agreement with a late-payment clause, an invoice template and five more Word documents. £15, one payment.
Get the Contract Pack — £15General information, not legal advice. Figures checked against GOV.UK and the Bank of England on 1 October 2026. Your contract may set its own late-payment rate instead of the statutory one.