In brief: When a client will not pay, the worst responses are silence and rage, usually in that order. The effective response is a staged process: diagnose why the payment has stopped, escalate in a deliberate sequence, use your statutory rights as leverage, and reserve legal action for the small number of cases that genuinely need it.

Most "won't pay" situations turn out to be "can't pay yet", "haven't processed it" or "dispute nobody surfaced". Each has a different fix, so the first job is finding out which one you have.

Step 1: diagnose before you escalate

Replace "any update?" with questions that produce facts:

  • Has the invoice been received and validated?
  • Is anything missing, such as a purchase order number?
  • Has the work been signed off internally?
  • Is any part of the amount disputed, and which part?
  • Which payment run is it scheduled for, and what date will cleared funds arrive?

The answers sort the situation into one of four buckets: process failure, cash difficulty, genuine dispute, or deliberate non payment. Our guide to why clients pay invoices late covers the full diagnostic. Everything below assumes you have asked and either received answers or silence.

Step 2: fix process failures fast

If the invoice went to the wrong person, lacks a PO or failed validation, correct it the same day and confirm the new payment date in writing. This is the most common cause and the easiest cure, and it is also the reason not to open with threats: a heavy first move against an innocent admin error costs goodwill for nothing.

Step 3: handle cash difficulty on your terms

A client in genuine difficulty deserves a structured response, not unlimited patience.

  • Ask for a written payment plan with specific dates and amounts.
  • Collect the plan by Direct Debit so each instalment arrives without a fresh decision. One mandate covers the schedule.
  • Pause further credit while the plan runs, in line with your contract.
  • Get part payment moving immediately. Money in motion is commitment; promises are not.

Watch for the pattern where every deadline produces a new story. Repeated broken promises move the situation into the deliberate bucket, whatever the stated reason.

Step 4: isolate and resolve genuine disputes

If part of the work is disputed, split the invoice. Demand payment of the undisputed amount now and resolve the disputed element separately with evidence: the contract, sign offs, delivery records. Do not let a 10% disagreement hold 100% of the money hostage. Put the resolution and any agreed adjustment in writing.

Step 5: the escalation ladder for everything else

  1. Day 1 overdue: a firm, polite notice stating the amount, the days overdue and a request for the exact payment date.
  2. Day 7 to 14: phone the decision maker, not just accounts payable. Confirm the outcome in writing the same day. State that statutory interest is now accruing.
  3. Day 21 to 30: a formal demand quantifying late payment interest and compensation, with a 7 to 14 day deadline and the next step named.
  4. Beyond 30 days: letter before action. For disputes with larger customers, the Small Business Commissioner offers a free complaints route. The 2026 reforms are also giving the Commissioner new powers to investigate and fine persistent late payers.
  5. Final step: county court money claim, statutory demand or professional debt recovery, guided by the sums involved and legal advice. Small claims routes suit lower value debts; costs and time rise sharply above that.

The ladder works because it is predictable. Clients learn that your process always moves forward, which makes early payment the easy option.

What not to do

  • Do not go silent. Unchased debts age badly and signal that your due dates are decorative.
  • Do not threaten what you will not do. An ignored ultimatum is worse than none.
  • Do not vent publicly. Naming a client online creates legal risk and burns future referrals.
  • Do not keep supplying on the same terms. New work for a non paying client converts your remaining leverage into more debt.

Protect the next invoice, not just this one

Once the money lands, change the terms of trade. Persistent late payers move to automatic collection, deposits or shorter terms. A client who refuses any of those is telling you the relationship only works when you carry the risk. The full prevention system is in how to stop chasing unpaid invoices.

NRTH makes the prevention side practical: invoices from Xero, QuickBooks or Sage are collected by Direct Debit on the due date, so routine payments stop depending on the client's to do list.

Frequently asked questions

How long should I wait before escalating?

Start the same week the invoice goes overdue. Early, calm contact resolves most cases and preserves your position for the few that harden.

Can I stop working for a client who owes money?

Usually, subject to your contract terms on suspension and termination. Check the agreement before pausing delivery, and communicate the pause in writing.

Is small claims court worth it?

For clear debts within the small claims limit, it is designed to be usable without a solicitor and the fee is added to the claim. Judgment does not guarantee payment, so weigh the client's ability to pay before filing.

What if the client has gone insolvent?

Register your claim with the insolvency practitioner promptly. Unsecured trade creditors often recover little, which is the strongest argument for tight credit limits and automatic collection before trouble starts.

A written process beats a strongly worded email every time.

See how NRTH removes routine invoices from the chase entirely, or talk to the team.

Sources and further reading

Last reviewed: 21 July 2026. This is general operational information, not legal advice. Take professional advice for significant or contested debts.