The Difference Between a Quote and an Estimate — and Why It Matters
“I gave him a quote and he’s now holding me to a price I can’t do it for.” This is one of the most common disputes in the trades – and it almost always comes down to one thing: the tradesperson said “quote” when they meant “estimate.”
These two words are not interchangeable. In a legal context, they mean completely different things. Understanding the difference – and using the right one – protects you from expensive disputes and sets clear expectations with customers from the start.
The Simple Distinction
A quote is a fixed price. Once a customer accepts a written quote, you are committed to delivering the described work at that price, regardless of whether the job takes longer than expected or your costs change. The only exception is if the scope of work changes.
An estimate is an approximation. It gives the customer an idea of likely cost, with the explicit understanding that the final price may vary depending on what’s discovered during the work.
One is a contractual commitment. The other is a projection. Both have a legitimate place in the trades – but you need to know which you’re providing and make it clear to the customer.
When to Quote (Fixed Price)
Use a quote when:
- The scope of work is clearly defined
- You have done a site visit and know exactly what’s involved
- Materials are specified (or a clear allowance is set)
- There are no significant unknowns that could change the cost materially
Examples where quoting is appropriate:
– Fitting a specified bathroom suite in a visible, accessible space
– Decorating a room to a specified spec
– Installing a fence of known length and specification
– Replacing a boiler with a like-for-like model
A quote gives the customer certainty – they know exactly what they’ll pay. This is a commercial advantage for you because customers who want certainty will often choose a professional quote over a vague estimate, even if the estimate looks cheaper initially.
When to Estimate
Use an estimate when:
- There are genuine unknowns that could materially change the cost
- Access to part of the job site is limited at the time of pricing
- Work involves what’s inside walls, under floors or beneath ground
- You’re pricing complex refurbishment work where the full extent won’t be known until demolition
Examples where an estimate is more appropriate:
– Groundworks or drainage where soil conditions are unknown
– Rewiring an old house where the existing wiring may need more extensive replacement
– Underpinning work where the extent of movement is unknown
– Renovation of an old building with concealed structural issues
Critical rule: if you use the word “estimate”, spell out clearly that the final price may differ – and give a realistic range, not just a single number. “Estimate: £4,000-£5,500 depending on what we find” is far better than “Estimate: around £4,000” which a customer will hold as a price.
The Grey Area: Provisional Sums
For larger or more complex jobs, many tradespeople and contractors use provisional sums – a fixed price quote for the known elements, with clearly labelled provisional allowances for the uncertain elements.
Example:
| Item | Price |
|---|---|
| Labour (all work) | £2,800 |
| Bathroom suite (specified) | £1,200 |
| Tiling – allowance (actual cost billed) | £600 |
| PROVISIONAL: replastering if required | £300 |
| Total (excluding provisional if not required) | £4,600 |
The provisional sum is flagged, explained, and only charged if the work is actually needed. Before carrying out any provisional work, the tradesperson should inform the customer and confirm they wish to proceed.
This approach gives customers near-certainty on cost while protecting you against the most common source of post-job disputes.
How to Present the Difference to Customers
Many customers don’t know the difference between a quote and an estimate – they use the words interchangeably. It’s your job to explain it clearly, because ambiguity always works against you.
On a quote:
“This is a fixed price quote for the described work. The price will not change unless additional work is required beyond what’s described – in which case we’ll agree a variation in writing before proceeding.”
On an estimate:
“This is an estimate based on what I’ve seen so far. The work involves [specific uncertainty], which means the final cost may vary. I’ll keep you informed as the job progresses and won’t exceed [upper limit] without your approval.”
Setting that upper limit is important. An open-ended estimate with no cap makes customers nervous – reasonably so. “I estimate £3,500 but won’t exceed £4,500 without your agreement” gives them confidence without locking you into an impossible price.
The Legal Position
If you provide a written quote and a customer accepts it, you have a contract at that price. If the job costs more than you quoted because you underestimated – not because scope changed – you absorb the difference.
This is why the distinction matters. Calling something a “quote” when you’re not certain of the price exposes you to doing work at a loss.
The key protections:
- Scope change clause – include in every quote: “Any changes to the agreed scope will be quoted separately and in writing before proceeding”
- Provisional sums – use them for uncertain elements rather than guessing
- Exclusions – be explicit about what the quote doesn’t include: “Quote does not include making good after tiling/replastering after boxing in” etc.
- Discovery clause – for work involving concealed elements: “If inspection reveals additional work not reasonably foreseeable from the site visit, we will provide a supplementary quote before proceeding”
None of these need to be written in legalese. Plain English, clearly stated, is more effective and more customer-friendly.
Handling Scope Creep
Scope creep – the gradual expansion of a job beyond what was originally agreed – is one of the most common sources of disputes and unpaid work.
The solution is simple: never carry out additional work without a written variation agreement. Even a WhatsApp message that says “while I’m here, the customer wants me to also [X] for [Y] – confirmed?” creates a record.
Common scenarios and how to handle them:
Customer asks you to do an extra small thing while you’re there:
If it’s genuinely small and goodwill is worth more than the 20 minutes it takes, you can choose to do it and say “I’ll leave that one with you.” If it’s more than trivial, say “I can do that – it’ll be an extra [£X], I’ll add it to the invoice. Shall I go ahead?”
You discover additional work that needs doing:
Stop. Tell the customer what you’ve found, what it’ll cost to address, and whether it needs to be done now or can be left. Get their decision in writing before you proceed.
The customer disputes the final bill because “it’s more than the estimate”:
If you provided an estimate and clearly communicated it was not a fixed price, you’re on solid ground – as long as you can show the final price was reasonable given what was found. If you called it a quote, you may have a problem. This is why the distinction matters.
Frequently Asked Questions
Is a verbal quote legally binding?
A verbal agreement can be legally binding, but it’s extremely difficult to enforce because there’s no record of what was agreed. Always confirm in writing – even a WhatsApp message summarising what was discussed is better than nothing.
What happens if I underquote a job?
If you’ve provided a fixed written quote and the job costs more than expected, you are generally bound by that price unless scope has changed. This is why accurate quoting – doing a thorough site visit, building in contingency for unknowns, and being conservative with your time estimates – matters so much.
Can I change a quote once it’s been accepted?
Once a customer has accepted a written quote, you can only change the price if the scope changes. If you realise you’ve made an error in the quote, the best approach is to tell the customer immediately, explain the situation honestly, and negotiate – rather than waiting until the end and presenting a higher bill.
What’s a reasonable contingency to add to a quote?
For straightforward work: 5-10%. For work involving unknowns (old buildings, groundwork, anything inside walls): 10-20%. For complex renovation or refurbishment work: up to 25%. Always label it clearly as contingency so the customer understands it may not be used.
Do I need a formal contract for every job?
For small jobs under £500, your quote and terms on it are usually sufficient. For larger jobs – anything over £1,000-2,000 – a simple written contract (which your quote can serve as) with clear scope, price, payment terms and a change control clause protects both parties.
What should I do if a customer disputes the final bill?
Stay calm. Refer to the written quote and any variation agreements. If there’s a genuine discrepancy between what was agreed and what you charged, acknowledge it and correct it. If you believe your billing is correct, explain your reasoning clearly in writing. Most disputes can be resolved this way. If not, Citizens Advice or a solicitor can advise on next steps.
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