TimerlessLate payment interest calculator
What a UK business client owes you on top of a late invoice: statutory interest and fixed compensation, under the Late Payment of Commercial Debts (Interest) Act 1998.
you can claim on top of the invoice, late.
| Interest rate | |
|---|---|
| Interest so far | |
| Fixed compensation | |
| Total now due, with the invoice |
Not late yet
From the day after, you can claim interest at a year and fixed compensation.
Before 2023
This calculator has the rates from 1 January 2023. For older debts, use the Bank of England base rate on the 31 December or 30 June before the payment became late, plus 8%.
Your figures go here
Put in the invoice total and the day it was due.
Timerless adds this to your reminders for you
It makes invoices from the hours it tracked, then drafts a reminder before the due date, on the day, and 7 and 21 days late. The three-weeks-late one claims the interest and compensation, worked out exactly like this. If they still don’t pay, it prepares a letter before action.
The rules, in plain words
Who can claim
You can claim when you and your client are both businesses. A sole trader counts, and so do public bodies. It doesn’t apply when you sell to consumers.
When interest starts
The day after the agreed due date. If you didn’t agree one, payment is due 30 days after your client got the invoice or the work, whichever is later.
The interest rate
8% a year plus the Bank of England base rate on 31 December (for debts that become late from January to June) or 30 June (July to December). It’s simple interest, and the rate stays fixed for that debt.
Fixed compensation
£40 for an invoice under £1,000, £70 from £1,000 to £9,999.99, and £100 for £10,000 or more. It’s per invoice. You can also claim reasonable costs of recovering the debt above that.
When your contract says otherwise
If your contract sets its own rate for late payment, that rate applies instead, as long as it’s a fair remedy. You can’t claim statutory interest on top of it.
The reference rates
| Payment became late | Base rate | You can charge |
|---|---|---|
| 1 July to 31 December 2026 | 3.75% | 11.75% |
| 1 January to 30 June 2026 | 3.75% | 11.75% |
| 1 July to 31 December 2025 | 4.25% | 12.25% |
| 1 January to 30 June 2025 | 4.75% | 12.75% |
| 1 July to 31 December 2024 | 5.25% | 13.25% |
| 1 January to 30 June 2024 | 5.25% | 13.25% |
| 1 July to 31 December 2023 | 5% | 13% |
| 1 January to 30 June 2023 | 3.5% | 11.5% |
Rates checked October 2026 against the Bank of England’s rate history. See also gov.uk on late commercial payments.
This is a guide, not legal advice. Check your contract, and get advice before you take a client to court.