Guide · checked 09/10/2026
Late payment letter templates for an unpaid invoice
Chase a late business invoice in three steps: a friendly reminder that assumes it was missed, a formal demand that claims statutory interest and the fixed sum under the Late Payment Act, and a final notice that gives 14 days before court action. Each should state the invoice, the amount, the due date and a clear deadline.
Free template: friendly reminder
This is letter 1 as ChaseLetter writes it, for an example £4,800.00 invoice due on 7 August 2026. The calculator fills in your own details.
Alex Morgan Morgan Design Studio 09/10/2026 Sam Patel Northfield Builders Ltd Invoice INV-0042: payment reminder Dear Sam Patel, I hope you are well. This is a reminder that £4,800.00 is outstanding on invoice INV-0042 dated 08/07/2026, which was due for payment on 07/08/2026. I have not received it yet, so it may have been missed. Please could you arrange payment of £4,800.00 by 16/10/2026? My payment details are on the invoice. If you have already paid, thank you. Please let me know the date and reference of the payment so I can match it to the invoice. If there is a problem with the invoice, please tell me as soon as possible so it can be sorted out. Kind regards, Alex Morgan Morgan Design Studio
Letter 2: formal demand
Send it if the reminder is ignored. It should say that the invoice is overdue, that statutory interest and the fixed sum are payable under the Late Payment of Commercial Debts (Interest) Act 1998, the exact figures (amount, interest to date, fixed sum, total), the interest still building each day, and a deadline of 7 days. GOV.UK suggests sending a new invoice when you add interest.
Letter 3: final notice before action
Refer to your earlier letters, restate the total, give 14 days to pay and say you may start a county court claim for the debt, interest, the fixed sum, the court fee and costs. If your client is a sole trader or another individual, the court process expects a formal Letter of Claim first; see letter before action for an unpaid invoice.
Tips that get invoices paid
- Be specific: invoice number, amount, due date and the date you want payment by.
- Keep the first letter friendly; most late payers simply missed it.
- Put your payment details on the invoice and point to them.
- Ask the client to tell you in writing if they dispute any part, so problems surface early.
ChaseLetter writes all three letters with your figures filled in. Letter 1 is free; letters 2 and 3 are a one-off £9.
Questions
What should a late payment letter include?
The invoice number and date, the amount outstanding, the due date, a clear deadline to pay, your payment details, and in later letters the statutory interest and fixed sum you are claiming.
How long should I wait before sending a formal demand?
A common approach is to give 7 days after a friendly reminder, then send a formal demand with another 7 days, then a final notice giving 14 days.
Can I add interest to an overdue invoice?
Yes, if your client is a business and your contract does not set its own substantial remedy. Statutory interest is 8% a year above Bank Rate, plus a fixed sum of £40, £70 or £100.