UK Late Payment Interest Calculator
Work out the statutory interest (currently 11.75% a year) and fixed compensation you can add to an overdue business invoice under the Late Payment of Commercial Debts (Interest) Act 1998.
Invoice details
Late fee breakdown
Total amount due now
$0.00
Effective rate
Interest-based late fee
$0.00
Flat fee (optional)
$0.00
Suggested client message
Statutory interest rates by period
The Bank of England rate used is fixed for each half-year: the rate on 30 June applies to debts that become overdue from 1 July to 31 December, and the rate on 31 December applies from 1 January to 30 June. Use the period in which your invoice became overdue — a later rate change does not affect it.
| Invoice became overdue | BoE reference rate | Statutory interest |
|---|---|---|
| 1 Jul 2026 – 31 Dec 2026 | 3.75% | 11.75% |
| 1 Jan 2026 – 30 Jun 2026 | 3.75% | 11.75% |
| 1 Jul 2025 – 31 Dec 2025 | 4.25% | 12.25% |
| 1 Jan 2025 – 30 Jun 2025 | 4.75% | 12.75% |
How UK statutory interest is calculated
Statutory interest is simple interest: take the amount owed, multiply by the annual rate, divide by 365 to get a daily amount, then multiply by the number of days the invoice is overdue. On top of the interest you can claim a fixed sum for debt recovery costs for each invoice.
Worked example
A £5,000 invoice paid 30 days late, overdue in the current period: £5,000 × 11.75% ÷ 365 = £1.61 a day. Over 30 days that is £48.29 in interest, plus £70 fixed compensation — £118.29 on top of the original invoice.
Fixed compensation for debt recovery costs
- Debts under £1,000: £40
- £1,000 to £9,999.99: £70
- £10,000 or more: £100
You can claim this once per invoice. If your actual recovery costs are higher, you can also claim the reasonable extra costs.
When you can claim
- Both you and your customer are businesses (sole traders and public sector bodies count). The Act does not cover sales to consumers.
- Your contract does not set its own late-payment interest rate. If it does, that rate applies instead — unless it is not a "substantial remedy", in which case you can still use the statutory rate.
- Interest starts the day after the agreed payment date. If no date was agreed, it starts 30 days after your customer received the invoice or the goods or services, whichever is later.
Wording to add to your invoices
Stating your rights on the invoice itself makes late payers far more likely to settle. Copy this into your payment terms:
Payment is due within 30 days of the invoice date. If payment is late, we reserve the right to claim interest and compensation for debt recovery costs under the Late Payment of Commercial Debts (Interest) Act 1998.Add it to an invoice
Embed this calculator on your site
Free for blogs, accountants and communities. Paste this code into any page — the calculator resizes itself and there's nothing to install.
UK late payment interest: FAQs
What is the statutory interest rate for late payment in the UK?
For invoices that became overdue in the current period it is 11.75% a year: the 8% statutory margin plus the Bank of England reference rate of 3.75%. The reference rate is fixed per half-year, so check the period in which your invoice became overdue.
Can I charge late payment interest to consumers?
Not under the Late Payment of Commercial Debts Act — it only covers business-to-business transactions. To charge a consumer interest you need a fair, clearly agreed term in your contract.
When does statutory interest start?
The day after the agreed payment date. If no payment date was agreed, it starts 30 days after your customer received the invoice or the goods or services, whichever is later.
How much compensation can I claim for a late invoice?
A fixed £40 for debts under £1,000, £70 for £1,000 to £9,999.99, and £100 for £10,000 or more — per invoice. You can also claim reasonable extra recovery costs if yours were higher.
Can I claim statutory interest if my contract has its own late fee?
Usually no — the contract rate applies instead. The exception is where the contractual remedy is not a "substantial remedy" (for example, a token rate), in which case the statutory rate can still apply.
How far back can I claim late payment interest?
In England and Wales you generally have six years from when the payment was due to bring a claim; in Scotland the period is five years. Interest runs until the debt is paid.
Not a UK business-to-business debt?
Use the general late fee calculator for contractual late fees, US-style monthly rates or EU statutory interest.
This calculator and guidance are for information only and are not legal advice. Rates checked against the Bank of England Bank Rate on each reference date. For disputed or large debts, speak to a solicitor.