SiteKiln gives you plain-English information, not legal advice. It's aimed at small UK construction businesses. Laws change and every job is different, so speak to a solicitor or adviser before you rely on this for a real dispute.
If a customer agrees a deal to settle a dispute -- a reduced bill, a partial refund, or "you fix X and we'll drop everything else" -- that can close things off so they can't come back for another bite later.
1. The short version
Two ideas matter here: accord and satisfaction (a clear settlement that replaces the old dispute) and promissory estoppel (situations where it's unfair for someone to go back on a promise they made and you relied on). The stronger and clearer your written settlement, the easier it is to shut down "we've changed our mind" attempts.
2. Where you stand legally
- Accord and satisfaction is basically: a new agreement (the accord) to settle a genuine dispute, followed by actually doing what was agreed (the satisfaction).
- To count as accord and satisfaction, you normally need:
- A real dispute or uncertainty about what's owed.
- A clear settlement deal both sides agree to (e.g. "we accept £3,000 as full and final settlement").
- Performance of that deal (payment made, remedial work done).
- Once there's proper accord and satisfaction, the original claims about the work are usually treated as settled, unless the settlement was reached by fraud, duress or similar.
- Separately, promissory estoppel can sometimes stop a party going back on a promise (like accepting less money or not enforcing strict rights) where:
- They made a clear promise.
- You relied on it.
- It would be inequitable (unfair) to let them change their mind afterwards.
- In part-payment situations, the usual strict rule is that taking less money doesn't wipe out the full debt -- but accord and satisfaction or promissory estoppel can soften that where there's a genuine compromise and real reliance.
- Courts are more likely to stand by a settlement where:
- The dispute was genuine.
- The deal is recorded in clear terms.
- Nobody was bullied or misled into accepting it.
So the law is basically on the side of clear, fair, final deals -- but woolly "half-agreed" chats are easy for a customer to wriggle out of.
3. Work out what was actually agreed
Before you argue "we had a deal", get really clear on what that "deal" was.
Dig out everything:
- Emails, WhatsApps, texts where you discussed the resolution.
- Any written "full and final" wording or signed notes.
- Bank records if they paid a specific "settlement amount".
Pin down basic questions:
- Did you agree a reduced price as final settlement?
- Did you agree to do specific remedial work in return for them dropping all other complaints?
- Was there any "full and final settlement" or "no further claims" wording?
Check performance:
- Have you actually done what you promised -- the remedial work, the refund, or the price cut?
- Have they done their bit -- paid, signed, confirmed in writing it's settled?
If all you've got is "we sort of agreed over the phone it would be alright", don't expect a judge to treat that as a watertight accord and satisfaction.
4. Check your own position honestly
Strength of your settlement:
- Is there a clear message from them agreeing the resolution terms?
- Did you follow up in writing to confirm what was agreed?
Behaviour around the deal:
- Were they under heavy pressure (e.g. "pay this now or we walk off site") that could look like duress?
- Did you hide any major issues when you agreed the deal?
Follow-through:
- Have you fully done what you promised in that resolution?
- Are there bits you still haven't done that they could fairly complain about?
Reality check:
- If the matter went to small claims, would the emails and actions look like a fair compromise, or more like something rushed and messy in the heat of an argument?
If the settlement was fair, documented and carried out, you're in a much stronger position to say "we already closed this off".
5. Respond when they try to reopen the dispute
When a customer comes back after a deal and says "we want more", your job is to calmly point back to the settlement.
Reply in writing and:
- Recap the original dispute in simple terms.
- Set out the settlement that you both agreed (date, terms).
- Confirm what each side has already done under that agreement.
Use clear language:
"On [date] we agreed that in full and final settlement of all issues about [job/address], I would [do X / refund £Y / reduce the price] and you would treat the matter as resolved."
Make your position clear:
"I have now completed/paid what we agreed. On that basis, I do not accept there is an open dispute or liability beyond that settlement."
If there's a genuinely new issue that wasn't covered (e.g. new damage, later defect), treat that separately, but don't let them roll old, settled points back in.
6. When estoppel might help you
Sometimes you don't have a perfect settlement document, but the customer's conduct and promises still matter.
Examples where promissory estoppel-type arguments can help:
- They clearly promised to accept reduced payment as full settlement, you relied on it and didn't pursue the rest, and now they're trying to claw more back.
- They agreed that if you did specific remedial work, they'd drop all other complaints, you did it, and now they're re-running the original claims.
Things to highlight:
- The promise they made (preferably in writing).
- How you relied on it (e.g. did extra work, gave a discount, wrote off part of a bill, didn't sue).
- Why it would be unfair to let them change their mind now.
Remember the limits:
- Estoppel is usually a shield not a sword -- it's often used to defend a claim, not create a new one.
- It won't normally help you if the "promise" was vague or you were strong-arming them.
You don't need to quote the cases -- just line your story up with those elements so a solicitor or judge can see what you're getting at.
7. Decide whether to hold the line or re-negotiate
Once they try to back out of the resolution, you've got a choice.
Hold the line if
- The settlement was fair, clear and fully carried out.
- Their new demand is just "we've changed our mind" or "we want a bit more because mate down the pub said so".
Re-negotiate (carefully) if
- There's new information (e.g. fresh report showing a real issue nobody knew about).
- You honestly missed something serious and the original deal no longer feels fair.
If you do adjust the settlement:
- Keep it tight -- a defined extra payment or small extra task, not a complete re-opening of everything.
- Put the new deal in writing, again calling it a full and final settlement.
On bigger sums, don't be shy about getting a solicitor to help shape the wording so it actually closes the problem down.
8. When you need proper legal advice
Get a solicitor or specialist adviser involved if:
- The settlement sum or job size is significant.
- The customer has instructed solicitors and is threatening to tear up the deal.
- There's talk of fraud, duress or misrepresentation in how the deal was reached.
A solicitor can:
- Tell you how strong your accord and satisfaction argument is on the actual facts.
- Advise whether promissory estoppel is worth running in defence.
- Draft a short, sharp letter setting out why the court should treat the matter as closed.
9. Common mistakes
- Not putting the resolution in writing -- shaking hands on a compromise and never confirming it in writing makes it easy for them to say "that's not what we agreed".
- Leaving terms woolly -- "we'll call it quits" or "we'll see how we go" is not a clear accord and satisfaction; you want "£X in full and final settlement of all claims about [job]".
- Not actually doing what you promised -- if you don't complete your side of the settlement, it's much easier for them to argue the deal is off.
- Letting yourself be bullied into an unfair deal -- agreements made because you're under improper pressure can be attacked later; better to pause and get advice than sign something you know is wrong.
- Assuming part-payment always kills the rest of the debt -- without a genuine compromise or estoppel, accepting less doesn't automatically wipe the balance, especially in strict law.
10. Who to contact
- Citizens Advice -- consumer problems -- general guidance on building disputes and settling complaints: 0800 144 8848 (free)
- Mediation services / trade bodies -- some trade bodies or local mediation schemes can help record a clear settlement both sides will stick to (varies)
- Solicitor specialising in construction / contract disputes -- for checking a proposed settlement or defending a "we want more" claim after a deal (paid)
- Legal expenses insurance helplines -- check your business or home policies for legal cover; many include a contract dispute helpline (often included)
11. Sources and legislation
- Accord and satisfaction -- common law principle: settling an existing dispute by a new agreement and its performance, discharging the original obligations. See British Russian Gazette v Associated Newspapers [1933] 2 KB 616.
- Promissory estoppel -- equitable principle preventing a party going back on a clear promise where the other relied on it. See Central London Property Trust v High Trees House [1947] KB 130.
- Part-payment of debts -- the rule in Pinnel's Case (1602) and Foakes v Beer [1884] UKHL 1, modified by genuine compromise and estoppel arguments.
- Consumer Rights Act 2015 -- underlying service rights that may be settled by agreement. legislation.gov.uk/ukpga/2015/15
12. Related guides on this site
- 9.1 Customer won't pay the final invoice
- 9.2 Customer claims defective work
- 9.5 Customer threatening court -- what to actually expect
- 9.9 Small claims court -- step by step guide for tradespeople
- 9.11 Customer demanding a refund -- when you have to and when you don't
- 8.6 Terms and conditions template -- domestic work
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