Which rules apply to you?
| Your situation | What you can usually claim |
|---|---|
| UK business invoicing another business, no interest rate in the contract | Statutory interest of 8% plus the Bank of England base rate, plus fixed compensation of £40, £70 or £100 per invoice, and reasonable extra recovery costs. |
| Your contract or invoice terms set an interest rate | The rate in your contract. Choose "Rate from my contract or invoice" above. |
| US freelancer | There's no single national rule. You can usually charge the late fee or interest agreed in your contract, but state laws limit how much. Check your state's rules before charging. |
| Invoicing a private individual (a consumer) | UK statutory interest doesn't apply. You can only charge what your agreement with them says, within consumer law. |
How to use this calculator
- Choose the type of interest. Pick UK statutory interest for business customers in the UK, or enter the rate from your contract.
- Enter the invoice amount that's still unpaid.
- Enter the due date and the payment date. If it's still unpaid, use today's date.
- Check the base rate. We fill it in from official Bank of England figures for your due date. You can change it.
How it's calculated
For UK statutory interest, the base rate is fixed for six months at a time. If your invoice became late between 1 January and 30 June, use the base rate on the 31 December before. If it became late between 1 July and 31 December, use the rate on 30 June. The calculator does this for you.
The fixed compensation is £40 for debts under £1,000, £70 for £1,000 to £9,999.99, and £100 for £10,000 or more. It can be claimed once per invoice. Sources: GOV.UK late commercial payments guidance and Bank of England Bank Rate history.
Worked example
Chris runs a small design studio in the UK. A business client had an invoice for £5,000 due on 1 August 2026 and paid it on 30 September 2026, 60 days late. Their contract didn't mention interest.
Chris can claim £166.58 on top of the £5,000 invoice.
Tip: put your payment terms, and the fact that you'll charge statutory interest on late payments, on every invoice. Clients who see it upfront tend to pay on time.
Frequently asked questions
When does an invoice count as late in the UK?
If you agreed a payment date, it's late the day after that date. Business customers can usually agree up to 60 days, and public authorities 30 days. If no date was agreed, the law says payment is late 30 days after the customer gets the invoice or you deliver the goods or service, whichever is later.
Can I charge statutory interest to individual customers?
No. UK statutory interest only covers debts between businesses, including public sector bodies. For private individuals, you can only charge interest if your agreement with them allows it.
Can I charge late fees in the US?
Usually yes, if the fee or interest rate was agreed in your contract or invoice terms before the work. Many states cap interest rates and some limit late fees, so check your state's rules and keep the amount reasonable.
Do I have to claim interest?
No. It's your right, not a requirement. Some freelancers mention it as a reminder and waive it if the client pays quickly. What matters is that your terms are clear before the work starts.