Quote or Estimate: Which Should You Give?
Written by James Walker · Last reviewed 16 August 2026
James Walker has 2 degrees in construction (BSc (Hons) Building Surveying · MSc Environmental Design of Buildings) and an extensive background in issue resolution, resolving over £4 billion of consumer issues.
The short answer
- A quote is a fixed price for defined work. An estimate is a considered projection that can change.
- Say which one you are giving. Documents that do not say cause the argument later.
- Quote where the scope is knowable. Estimate where it genuinely is not.
- An estimate that moves substantially without explanation destroys trust even when justified.
- Provisional sums let you quote firmly on most of a job and flag the genuinely unknown parts.
The difference
A quote commits you. If you have quoted and the job takes longer than you thought, that is your risk unless the scope changed.
An estimate does not commit you in the same way, but it also does not give the customer certainty, and customers strongly prefer certainty.
When to estimate
Where the scope genuinely cannot be established in advance. Work behind a wall. Foundation depth. The condition of timber under a roof covering. Pipework under a floor.
Quoting a firm price on genuine unknowns means either guessing or padding heavily, and the customer pays for your uncertainty either way.
The better middle ground
Quote firmly on everything you can see, and use provisional sums for the parts you cannot.
That gives the customer a real number for most of the job, flags exactly where it could move, and shows you have thought about it. It is far stronger than an estimate for the whole thing, and far more honest than a firm quote that will not survive contact with the job.
State the price basis clearly
Whichever you give, label it. And where it is an estimate, say what would make it move and by roughly how much.
Customers accept uncertainty they were told about. They do not accept discovering it on the final invoice.