How to Chase an Unpaid Invoice (UK): Steps, Emails and Your Rights
Most late invoices get paid after a polite, well-timed reminder. Here is a simple chasing timeline, four email templates and what to do if a client still will not pay.
To chase an unpaid invoice, send a polite reminder on the due date, follow up a few days later, then phone the client. If it is still unpaid after two weeks, send a firm email that mentions late payment interest. At around 30 days overdue, send a formal letter before action giving a final deadline. Most invoices are paid at the first or second step, as long as you chase early and stay professional.
Before you chase: check the basics
- Did the invoice go to the right person or accounts address?
- Does it include a due date, your bank details and any purchase order number the client needs?
- Is the invoice correct? A wrong amount or missing detail is a common reason invoices sit unpaid. Compare it against our invoice checklist.
A simple chasing timeline
| When | Action | Tone |
|---|---|---|
| Due date | Friendly reminder email with the invoice attached | Helpful |
| 3 days overdue | Second email asking for a payment date | Polite |
| 7 days overdue | Phone call to the person who pays | Direct |
| 14 days overdue | Firm email mentioning interest and fees | Firm |
| 21 days overdue | Pause further work; final demand | Formal |
| 30+ days overdue | Letter before action, then court or a debt collector | Legal |
Unpaid invoice email templates
1. On the due date
Subject: Invoice INV-0042 due today
Hi Jane, just a friendly reminder that invoice INV-0042 for £575.00 is due today. I have attached a copy. If it is already paid, thank you, please ignore this.
2. A few days overdue
Subject: Invoice INV-0042 now overdue
Hi Jane, I have not yet received payment for invoice INV-0042 (£575.00), which was due on 17 November. Could you let me know when it will be paid? Bank details are on the invoice.
3. Two weeks overdue
Subject: Overdue invoice INV-0042, action needed
Hi Jane, invoice INV-0042 for £575.00 is now 14 days overdue. Please arrange payment within 7 days. After that I will add statutory late payment interest and compensation as allowed under the Late Payment of Commercial Debts (Interest) Act 1998.
4. Final demand
Subject: Final notice: invoice INV-0042
Dear Jane, despite previous reminders, invoice INV-0042 remains unpaid. Unless £575.00 plus interest is received by 15 December 2026, I will start legal proceedings to recover the debt without further notice.
Want the original invoice email right? See how to send an invoice.
Your legal rights in the UK
For business-to-business sales, the Late Payment of Commercial Debts (Interest) Act 1998 lets you claim:
- Statutory interest at 8% above the Bank of England base rate, from the day after the due date.
- Fixed compensation of £40 for debts under £1,000, £70 for £1,000 to £9,999.99, and £100 for £10,000 or more.
- Reasonable recovery costs beyond that, such as debt collection fees.
If no payment date was agreed, payment is due 30 days after the customer received the invoice or the goods or services, whichever is later. We explain how to calculate it in late payment interest UK. The rules do not apply to consumers, so put late fees in your terms if you work for individuals.
If the client still will not pay
- Letter before action. A formal letter stating the debt, interest and a deadline (usually 14 days, or 30 days for individuals and sole traders) before you go to court.
- Debt collection agency. Many work on a no-win, no-fee basis for business debts.
- Small claims court. In England and Wales you can claim online through Money Claim Online. Claims up to £10,000 normally go to the small claims track.
How to avoid late payments next time
- Agree clear payment terms in writing before you start.
- Take a deposit on larger jobs using a proforma invoice.
- Invoice the day the work is finished.
- Put your bank details and due date in large, clear text. Our free invoice generator highlights the balance and due date on every invoice.
Frequently asked questions
How soon can I chase an unpaid invoice?
You can send a polite reminder on the due date itself and follow up a few days after. There is no need to wait weeks; a clear, early reminder is the most effective step.
Can I charge interest on an unpaid invoice?
Yes, for business-to-business sales. Under the Late Payment of Commercial Debts (Interest) Act 1998 you can claim interest at 8% above the Bank of England base rate, plus a fixed compensation sum of £40 to £100 depending on the size of the debt.
What if the client is a consumer, not a business?
The late payment legislation does not apply to consumers. You can only charge interest or fees if you agreed them in your terms before the work started.
When should I send a letter before action?
When reminders, calls and a final demand have not worked, usually around 30 days overdue. It sets a final deadline, normally 14 days, or 30 days if the debtor is an individual or sole trader, before you start court action.
How do I take a client to court for an unpaid invoice?
In England and Wales you can claim online through Money Claim Online. Claims up to £10,000 normally go to the small claims track, which is designed to be used without a solicitor.
Create your invoice now
Add your logo, line items and tax, see it on a real A4 page, then download a clean PDF. Free, with no sign up.
