Quote vs estimate: what's the difference?

People use the words quote and estimate as if they mean the same thing. They don't. One ties you to a fixed price. The other leaves room to move. Get them mixed up and you can end up legally bound to a number you only meant as a rough guide. Here is what each one actually means and when to use which.

What a quote means

A quote is a fixed price. You are telling the customer: this is what the job will cost, full stop. Once they accept it, that figure is what you have agreed to. If the job ends up costing you more than you expected, that is usually your problem to absorb, not theirs.

Because a quote is a firm commitment, you should only give one when you understand the job properly. That normally means you have seen the site, measured up, and know what materials you will need. A quote works best for jobs with a clear, fixed scope: a defined number of sockets, a single bathroom suite, a known length of fencing.

What an estimate means

An estimate is your honest best guess at the cost based on what you know right now. It is not a promise. If the work turns out to be bigger or more complicated than expected, the final figure can change. Estimates suit jobs where you genuinely can't see everything up front: hidden pipework, unknown wall conditions, or a project the customer is still making decisions about.

The catch is that the word on the paper matters less than how a court would read it. If you label something an estimate but write it like a fixed price, with no caveats and exact figures, a customer can reasonably argue they were quoted. Be clear in writing about which one you are giving.

How to protect yourself either way

Whichever you send, a few habits keep you out of trouble:

• Say the word clearly on the document: write "Quote" or "Estimate" at the top so there is no doubt.
• Spell out what is and is not included. Most disputes are about scope, not the price itself.
• On an estimate, explain what could change the price and roughly by how much.
• Put a validity date on it (for example, valid for 30 days) so old prices don't come back to bite you when material costs move.
• Keep a record of what you sent and when, so you can refer back if a customer queries it.

Which should you use?

If you have seen the job and you are confident about the scope, give a quote. It looks more professional and customers prefer the certainty of a fixed price. If there are real unknowns, give an estimate and say plainly what might move the number. Never give a fixed quote just to win the job and then hope the extras cover you. That is how you end up working for free or arguing with a customer.

If you are not sure what belongs on the document itself, read our guide on what every professional quote should include. And if VAT applies to your work, our guide on VAT for sole traders explains when you need to add it.