They Sent an Offer, Then Changed the Price
Once you accept a quote it generally forms a contract at that price — and a trader cannot simply raise it because the job proved less profitable than they hoped. An estimate is a different document with different consequences. This guide explains which one you actually have, when a price can legitimately move, when it cannot, and what to do the moment the number changes.
Quote or estimate? The difference decides everything
This is the whole question, and most people discover it only after the argument has started. The two documents do very different legal work.
| Quote | Estimate | |
|---|---|---|
| What it is | A firm offer to do defined work for a stated price. | An informed indication of likely cost. |
| On acceptance | Generally forms a contract at that price. | No fixed price is agreed. |
| Can the price move? | Only by agreed variation, or where the contract genuinely provides for it. | Yes, within reason — it was never fixed. |
| Typical wording | "We will carry out the following for £X." | "We estimate this will be in the region of £X." |
The label at the top is not decisive. A document headed "estimate" that gives one exact figure for a fully specified scope may still be treated as a quote, and a vague "quote" full of provisional sums may not be as fixed as it looks. Substance beats heading.
When a price CAN legitimately change
Not every increase is sharp practice. These are the situations where more money is a fair ask — provided it is handled properly.
- You changed your mind — different tiles, an extra socket, a wider opening. Your variation, your cost.
- Something genuinely hidden turned up — rot beneath a floor, unsafe wiring in a wall, no foundations where there should be some.
- A provisional sum is replaced by a real figure, where the quote flagged it as provisional from the start.
- The contract provides for it and you knew — for example a stated materials-price fluctuation clause on a long project.
- Access or conditions differ materially from what you described when the price was given.
In every one of these the correct process is identical: stop, tell you, price the extra separately, get written agreement, then continue. An increase that skips those steps is a problem even when the underlying reason was legitimate.
When it cannot
Equally, these are not reasons to raise an agreed price after the fact.
- The trade underestimated the labour or the materials. Pricing risk sits with the person who set the price.
- Materials went up after the quote, with no fluctuation clause and no unusual delay caused by you.
- The job took longer than hoped for reasons within their control.
- They have had a better-paid job come along and want this one to match.
- The increase appears only on the final invoice, with no discussion at the time the extra work was supposedly done.
- You are told the original figure was "only an estimate" when the document and the conversation both said otherwise.
What to do when the price jumps
Move quickly, stay factual, and get everything into writing. The aim is to separate what you genuinely owe from what you do not.
- Ask for the increase in writing, itemised — what changed, why, and what each item costs.
- Compare it against your original document and any variations you agreed. Line them up side by side.
- Pay the undisputed amount. This matters: it shows good faith and removes the argument that you are simply refusing to pay.
- Set out the dispute in writing, quoting the original scope and price and asking them to evidence the variation you supposedly authorised.
- If the work is unfinished, agree in writing what happens next before they continue — do not let more work accumulate on a disputed basis.
- If it cannot be resolved, follow the order in our payment disputes guide.
Preventing it on the next job
- Get three written quotes on the same scope — the outlier is usually the one that will move later.
- Ask explicitly, in writing, whether the price is fixed. The reply is now evidence whichever way it goes.
- Require the quote to name exclusions as well as inclusions — what is not in the price is where surprises live.
- Agree that no variation is chargeable unless confirmed in writing first. Most trades are happy with this; the ones who are not have told you something.
- Pay the deposit by credit card for Section 75 protection — see how to pay a builder.
- Tie stage payments to milestones you can check, not dates in the calendar.
Price change FAQs
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