Most late invoices are just admin oversights — a follow-up or two and the money arrives. But occasionally you run into a client who genuinely won't pay: they're disputing the work, stalling, or have simply gone quiet. It's frustrating, but there's a clear process for handling it. Here's what to do, step by step, without burning bridges unnecessarily or letting it drag on indefinitely.
First: Make Sure You've Done Everything Right
Before escalating, check your side of the process:
Was the invoice sent to the right person — billing contact, not just whoever you dealt with?
Did the invoice have a clear due date on it?
Did your original quote or agreement set out the payment terms?
Have you followed up at least once in writing?
If any of these are missing, address them before you escalate. A client who hasn't received a proper invoice with a due date can legitimately claim they didn't know when to pay — and it weakens your position if things go further.
Step 1: Follow Up Professionally
The first response to non-payment is always a polite, professional written follow-up — email is fine. Assume oversight, not bad faith. Most clients who don't pay immediately just haven't got around to it.
Keep it short and neutral:
"Hi [Name], just following up on invoice INV-042 for $[amount], which was due on [date]. Could you let me know when I can expect payment? Happy to resend the invoice if that would help."
Give it 3–5 business days. If no response, follow up again — slightly more direct, but still professional.
Step 2: Try a Different Channel
If emails aren't getting a response, try calling. It's harder to ignore a phone call than an email. Keep it brief and friendly — you're just following up, not confronting.
If you can't reach them directly, try a different contact at the company — a director, an accounts manager, or whoever signs off payments. Sometimes invoices genuinely get lost in the wrong inbox.
Step 3: Issue a Formal Payment Demand
If 14–21 days have passed with no resolution, move from informal follow-ups to a formal written demand. This should:
State the invoice number, amount, and original due date
Reference any late payment fees that apply under your terms
Give a clear deadline for payment — 7 days is standard
State what action you'll take if payment isn't received by that date
"Dear [Name], This is a formal demand for payment of invoice INV-042 for $[amount], due on [date] and now [X] days overdue. Under the terms agreed at the time of the work, a late payment fee of [X]% per month applies to this balance. Please arrange payment of $[total] by [date]. If payment is not received by this date, I will proceed with formal debt recovery proceedings without further notice."
Send this by email and, if the amount warrants it, by recorded post.
Step 4: Apply Late Payment Fees
If your original invoice or quote included a late payment clause, you're entitled to add fees to the outstanding amount. This serves two purposes: it compensates you for the delay, and it creates additional incentive for the client to pay sooner rather than later.
You can only charge late fees if you stated them upfront. If your invoices don't currently include a late payment clause, add one to every invoice going forward.
Step 5: Escalate to Formal Recovery
If the formal demand doesn't produce payment, you have several routes:
Small claims court
For smaller amounts — up to £10,000 in England and Wales, $10,000–$25,000 in most US states, and similar thresholds in other countries — small claims is a fast, inexpensive option. You file the claim, serve the defendant, and either reach a settlement or go to a hearing. Judges take a dim view of clear-cut unpaid invoices backed by a paper trail. Most claims settle before reaching a hearing.
Debt collection agency
A commercial debt collector will pursue the debt on your behalf for a fee — typically 10–25% of the recovered amount. It removes the admin from your plate but costs you a portion of what you're owed. Worth considering for larger amounts where the time cost of pursuing it yourself is significant.
Statutory demand (UK)
In the UK, if a business owes you more than £750, you can serve a statutory demand. If they don't pay within 21 days, you can apply to wind up the company. It's a serious step — and clients know it. The threat of a statutory demand often produces payment quickly.
What to Do With Your Documentation
At every stage, keep records of everything: the original quote, the invoice, every follow-up email or call log, and any responses from the client. If you end up in court, this paper trail is your case. Without it, even a legitimate debt becomes hard to prove.
How to Reduce the Risk Next Time
Take a deposit on significant jobs — it filters out unreliable clients before you start
Include clear payment terms on every quote and invoice
Invoice promptly — the day the job is done, not a week later
Use automatic reminders — tools like Clervo send payment reminders before and after the due date so you're not manually tracking every outstanding invoice
Check new clients — for large jobs, a quick credit check or a reference from another supplier is worthwhile
The clients who won't pay are a small minority. A good system — clear terms, prompt invoicing, and consistent follow-up — means you'll rarely need to go beyond step two.