Letter Before Action for Unpaid Invoices

What is a letter before action?

A letter before action — sometimes called an LBA or a letter before claim — is a formal written notice sent to a debtor before you take formal proceedings. It tells them clearly that you intend to pursue the debt through a formal process if they do not pay within a specified period.

It is not the same as a final demand, even though the two are often confused. A final demand is a strong payment request — the last in a series of chasing letters. A letter before action is a formal legal step that signals the end of the chasing phase and the beginning of the formal recovery process.

Courts in England and Wales expect to see that a letter before action has been sent before a claim is issued. Failure to send one — or sending one that does not meet the basic requirements — can result in cost penalties even if you win your case. Getting this step right matters.

What to include in a letter before action for an unpaid invoice

A letter before action does not need to be long or complicated. It does need to be clear, complete, and firm. Include the following:

• The amount owed — state the invoice amount clearly, including any statutory interest that has accrued and the fixed compensation sum you are entitled to claim under the Late Payment of Commercial Debts (Interest) Act 1998. For debts under £1,000 that is £40, for debts between £1,000 and £9,999 it is £70, and for debts of £10,000 or more it is £100.
• The invoice details — include the invoice number, the date it was raised, the date payment was due, and a brief description of the goods or services it relates to.
• The payment deadline — give the debtor a clear deadline to pay. Allow 14 days if the debtor is a business. If the debtor is a sole trader or other individual, the Pre-Action Protocol for Debt Claims applies: allow 30 days and enclose the protocol's information sheet and reply form. Be specific: state the exact date by which payment must be received.
• Your intended next step — state clearly what you will do if payment is not received by the deadline. This might be issuing a court claim, referring the matter to a neutral decision process, or both. Vague threats carry less weight than specific ones.
• Payment details — include your bank details or another clear method of payment so that there is no practical barrier to the debtor paying immediately.
• An invitation to respond — if the debtor has a genuine dispute about the invoice, invite them to set it out in writing within the same deadline. This is good practice and helps you understand what you are dealing with before taking the next step.

How to send a letter before action

Send it in a way that creates a record of delivery. Email with read receipt is acceptable and creates a clear timestamp. A recorded or tracked letter adds a physical paper trail. For higher-value debts, sending by both email and recorded post is a sensible precaution.

Keep a copy of everything — the letter itself, the delivery confirmation, and any response you receive. This documentation will be important if the matter proceeds to a neutral decision process or a court claim.

What happens if the letter before action is ignored?

If the deadline passes with no payment and no response, you have a clear choice to make about next steps.

For straightforward unpaid invoices where the debt is not contested, a court claim through the small claims track — for debts up to £10,000 — is one option. That limit applies in England and Wales (Northern Ireland has its own, lower limit), and since 22 May 2024 defended small claims for a specified sum are automatically referred to a free HMCTS mediation session first. For larger debts, or where the other side has disputed the invoice, the small claims track is either unavailable or unsuitable.

For invoices up to £150,000, whether disputed or simply unpaid, a private neutral decision process is often the more practical route if both parties agree to use it. It is faster than court, has a fee set by the amount in dispute and known in advance, produces a binding outcome, and the process is private. See our full guide on recovering unpaid invoices without going to court.

At Dispute Neutral, a binding decision is issued within 10 business days of the matter being ready. It is made on the documents by an independent lawyer with at least 15 years' practical experience, acting as an expert, not an arbitrator. There is no hearing. Neither party needs a solicitor. And both sides know exactly what the process will cost before they agree to it.

What if the debtor responds but still doesn't pay?

A response is not always a resolution. Sometimes a debtor responds to a letter before action with a partial payment, a promise to pay, a request for more time, or a dispute about the invoice.

Each of these needs a different response. A partial payment should be acknowledged but should not be treated as full settlement unless you explicitly agree to it. A promise to pay should be confirmed in writing with a specific date. A request for more time should be considered carefully — it may be genuine, or it may be a stalling tactic.

A dispute about the invoice is the most important response to handle carefully. If the debtor raises a genuine question about the work, the amount, or the contract, you are now dealing with a disputed debt rather than a simple refusal to pay. A dispute delays payment, but it does not remove your right to statutory interest and fixed compensation: if the debt turns out to be owed, both still run from the original due date. (A court can reduce interest where the supplier's own conduct justifies it, under section 5 of the Late Payment of Commercial Debts (Interest) Act 1998.) If both sides agree, a neutral decision process that resolves the underlying disagreement is often the most appropriate next step.

Include Dispute Neutral in your terms of business from the outset

The most effective way to handle a letter before action situation is to have already agreed — in your standard terms of business or engagement letter — how any dispute will be resolved if it arises.

Businesses and professionals that include a Dispute Neutral clause in their terms ensure that if an invoice goes unpaid and a letter before action produces no result, the next step is already agreed. There is no need to persuade a reluctant debtor to engage with a formal process. The process is already part of the contract.

Draft clauses suitable for incorporation into your terms of business or client engagement letters are available in the Include us section of the site.

Do I need a solicitor to write a letter before action?

No. A letter before action does not need to be drafted by a solicitor. It needs to be clear, complete, and firm — stating the amount owed, the deadline for payment, and the specific next step you intend to take. Many businesses write their own letters before action without any legal assistance. If the matter subsequently proceeds to a neutral decision process or a small claims court claim, you do not need a solicitor for those steps either.

How long should I give the debtor to respond?

Allow 14 days where the debtor is a business. This matches the Practice Direction on Pre-Action Conduct, which suggests 14 days in a straightforward case. If the debtor is a sole trader or other individual, the Pre-Action Protocol for Debt Claims applies instead: give 30 days and enclose the information sheet and reply form it requires. Either way, state an exact date, not just a number of days, so there is no doubt about when the deadline falls and when you can take the next step.

Can I send a letter before action by email?

Yes. Email is widely accepted as a valid method of sending a letter before action, provided you can demonstrate it was sent and — ideally — received. Use an email that generates a read receipt or delivery confirmation, and keep a copy of the sent email with its timestamp. For higher-value debts, follow up with a recorded postal copy as well to create a complete paper trail.

What if the debtor claims they never received the letter before action?

This is why delivery method matters. If you have sent by tracked post or email with delivery confirmation, you have evidence that the letter was sent and received. If the debtor claims non-receipt despite evidence of delivery, that position is unlikely to carry much weight in a subsequent neutral decision process or court claim. Keep your delivery records carefully and include them in any subsequent submissions.

Ready to take the next step after your letter before action?

If your letter before action has produced no payment and no satisfactory response, and the other side will agree to it, Dispute Neutral offers a private route to a binding decision, with a fee known in advance and no need for solicitors.

Want to make sure your terms of business already include an agreed dispute resolution process? Draft clauses are available in the Include us section.

Private • Fixed-fee • Binding decision in 10 business days once the matter is ready