Letter Before Action Template for an Unpaid Invoice (UK)

A letter before action (sometimes called a letter before claim or letter of claim) is the formal letter you send before starting a court claim for an unpaid invoice in England and Wales. It's the last step before court, and on its own it often gets the invoice paid, because it shows you're organised and serious.

This guide explains when to send one, what it must contain, the different rules for company and individual clients, and gives you a template. It's general information, not legal advice. For large or disputed debts, consider a solicitor.

When to send a letter before action

Send it after your normal reminders and final notice have failed, typically 45 to 60 days after the due date. Before that, the steps in overdue invoice email template and final notice letter for an unpaid invoice are usually enough.

The courts expect parties to exchange information and try to settle before a claim is issued. If you skip this step, a court can take it into account, for example when deciding costs.

Which rules apply: company or individual?

Your client is a company or other business entity (not a sole trader). The Practice Direction on Pre-Action Conduct applies. You should send a letter setting out the claim and give a reasonable time to respond. For a straightforward debt, 14 days is generally treated as reasonable.

Your client is an individual, including a sole trader. The Pre-Action Protocol for Debt Claims applies. It's stricter:

• the letter must include specific information about the debt;
• you must enclose the Information Sheet, Reply Form and Financial Statement from the protocol's annex;
• the debtor has 30 days to respond;
• if they reply that they need time, for example to get debt advice, you should allow reasonable time.

The protocol and its forms are published on the Justice.gov.uk Civil Procedure Rules pages.

Scotland and Northern Ireland have different procedures.

What to include

At a minimum:

1. Your name and address, and the client's correct legal name and address.
2. The amount owed, broken down by invoice (number, date, amount, due date).
3. What the work or goods were, and the contract or agreement the invoice relates to.
4. Any interest and compensation you're claiming, and the legal basis, such as the Late Payment of Commercial Debts (Interest) Act 1998 for B2B debts.
5. How to pay, with bank details and a payment reference.
6. A deadline to pay or respond.
7. What you'll do if they don't: issue a claim in the County Court without further notice.
8. Copies of the invoices and key documents, or an offer to provide them.

Keep the tone factual. A letter before action isn't the place for frustration.

Template: company client (14 days)

[Your business name] [Your address] [Email] · [Phone]

[Date]

[Client legal name] [Client registered address]

LETTER BEFORE ACTION

Unpaid invoice INV-1042 – £2,400

Dear [Name],

We provided [brand design services] to you under our agreement dated [3 February 2026]. We issued invoice INV-1042 on [3 March 2026] for £2,400, payable by [2 April 2026]. Despite our reminders of [3 April], [10 April], [17 April], [2 May] and our final notice of [17 May], the invoice remains unpaid.

The amount now due is:

• Invoice INV-1042: £2,400.00
• Statutory interest under the Late Payment of Commercial Debts (Interest) Act 1998, at 8% above the Bank of England base rate, from [3 April 2026] to the date of this letter: £[amount]
• Fixed compensation under the same Act: £70.00
• Total: £[total]

Interest continues to accrue at £[daily amount] per day.

Please pay the total within 14 days of the date of this letter, by [date], to: [Account name], sort code [xx-xx-xx], account [xxxxxxxx], reference INV-1042.

If you dispute any part of this debt, please tell us in writing within the same period, explaining why and enclosing any documents you rely on.

If we don't receive payment or a response by [date], we intend to issue a claim against you in the County Court without further notice. This may increase the amount you have to pay, including court fees and costs.

We'd much prefer to resolve this without court proceedings.

Yours sincerely, [Your name] [Your business name]

Enclosed: invoice INV-1042; [agreement dated 3 February 2026].

The fixed compensation under the Act is £40 for debts under £1,000, £70 for £1,000 to £9,999.99, and £100 for £10,000 or more. Background on calculating interest is in how to charge statutory interest on overdue invoices.

Template changes for an individual or sole trader (30 days)

If the client is an individual or sole trader, adapt the template:

• Title it Letter of Claim.
• Give 30 days from the date of the letter to respond.
• Enclose the Information Sheet, Reply Form and Financial Statement from the Pre-Action Protocol for Debt Claims, and say where to send the Reply Form.
• Say whether you'd accept payment by instalments.
• Note that they may wish to seek free debt advice, and allow reasonable time if they ask for it.
• The Late Payment Act applies only to business debts. If the sole trader engaged you for their business, it applies. If they're a consumer, it doesn't.

How to send it

• Send it by email and first-class post, or recorded delivery, and keep proof of sending.
• Address it to the registered office for a company (check Companies House).
• Keep a clear record of every reminder you've sent, with dates.

What happens next

Many debts are paid at this stage. If not:

• Money Claim Online lets you issue a claim for a fixed amount online.
• Most claims up to £10,000 go to the small claims track, designed for people without lawyers.
• If the client doesn't respond to the claim, you can ask for judgment in default.

More on the full process in what to do when a client doesn't pay, and on the UK rules in our UK late payment guide.

FAQ

What is a letter before action?

A formal letter sent before starting court proceedings, setting out what's owed and giving the debtor a final chance to pay or respond.

How long do I have to give in a letter before action?

For a company client, 14 days is generally reasonable for a simple debt. For an individual or sole trader, the Pre-Action Protocol for Debt Claims requires 30 days.

Do I need a solicitor to send one?

No. You can send it yourself. A solicitor's letter can carry more weight for larger debts.

Can I add interest in a letter before action?

Yes. For B2B debts, you can claim statutory interest and fixed compensation under the Late Payment of Commercial Debts (Interest) Act 1998.

Fewer invoices that need a letter

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