Duly Paid / Calculator
Late payment calculator
Statutory interest and fixed compensation on an overdue business invoice, worked out to the day, using the right Bank of England reference rate for when it fell overdue. Free, no sign-up.
Enter the amount and the invoice date to see the statutory interest and compensation you're entitled to.
How the maths works
The Late Payment of Commercial Debts (Interest) Act 1998 lets a business claim simple interest on a late invoice from another business. The rate is 8% above the Bank of England's reference rate, and the reference rate is fixed for each half-year:
- debts that become overdue between 1 January and 30 June use the base rate in force on the previous 31 December;
- debts that become overdue between 1 July and 31 December use the base rate in force on 30 June.
That rate then stays fixed for the life of the debt, even if the Bank of England changes rates later. Interest is:
Example: a £10,000 invoice paid 60 days late in 2026 attracts £10,000 × 11.75% ÷ 365 × 60 = £193.15 in interest, plus £100 fixed compensation. That's the same figure the government uses in its own example.
If no payment date was agreed, payment is due 30 days after the later of the invoice arriving or the goods or services being delivered. Agreed terms of more than 60 days between businesses are only valid if they were expressly agreed and aren't grossly unfair to the supplier.
Recent reference rates
| Debt became overdue | Base rate on | Reference rate | Statutory rate |
|---|---|---|---|
| 1 Jul 2026 to 31 Dec 2026 | 30 Jun 2026 | 3.75% | 11.75% |
| 1 Jan 2026 to 30 Jun 2026 | 31 Dec 2025 | 3.75% | 11.75% |
| 1 Jul 2025 to 31 Dec 2025 | 30 Jun 2025 | 4.25% | 12.25% |
| 1 Jan 2025 to 30 Jun 2025 | 31 Dec 2024 | 4.75% | 12.75% |
| 1 Jul 2024 to 31 Dec 2024 | 30 Jun 2024 | 5.25% | 13.25% |
| 1 Jan 2024 to 30 Jun 2024 | 31 Dec 2023 | 5.25% | 13.25% |
See every half-year back to 2018 →
Fixed compensation
| Size of the debt | Compensation |
|---|---|
| Up to £999.99 | £40 |
| £1,000 to £9,999.99 | £70 |
| £10,000 or more | £100 |
It's claimable once per invoice, on top of interest. If your reasonable costs of recovering the debt were higher, you can also claim the difference.
Who it applies to
Both you and your customer must be acting in the course of business. That includes sole traders, partnerships, companies and public bodies. It doesn't apply to private individuals (consumers). If your customer is a consumer, chase the full amount with plain reminders instead; Duly Paid does that automatically.