What’s the Difference Between a Quote and an Estimate? A Tradesperson’s Guide

“I’ll get you a quote over” and “I’ll send you an estimate” — most tradespeople use these phrases interchangeably. But legally, they mean very different things. And if you get them mixed up, you could find yourself locked into a price you can’t change, or in a dispute with a customer who expected a fixed price and got a nasty surprise.

What Is a Quote?

A quote is a fixed, binding price for a specific piece of work. Once a customer accepts a quote, it becomes a legally enforceable contract. If the job turns out to be more complicated than expected, you generally cannot charge more than the quoted price — unless you have agreed a variation in writing.

For example: if you quote £1,800 to fit a new bathroom suite and the customer accepts, that’s the price — even if it takes you longer than planned.

What Is an Estimate?

An estimate is a best guess at what a job is likely to cost. It is not legally binding in the same way as a quote. You can charge more than your estimate if the actual costs come in higher — but only if the final amount is a reasonable reflection of the work done.

That said, “not legally binding” does not mean you can charge whatever you like. Under consumer protection law, any additional charges must be reasonable and justifiable. If you estimate £500 and then invoice £2,000 with no good reason, you could face a dispute.

When Should You Quote and When Should You Estimate?

The right choice depends on how well-defined the job is before you start.

Use a fixed quote when:

• The scope of work is clear and unlikely to change (fitting a new boiler, replacing a bathroom suite, painting and decorating a room).
• Materials can be costed accurately in advance.
• You have done this type of job many times before and know exactly how long it takes.

Use an estimate when:

• The full scope won’t be known until work begins (for example, opening up a wall to find a leak).
• There is a risk of discovering additional problems that will affect the cost.
• The customer wants a rough idea of cost before committing to a full survey.

The Golden Rule: Be Clear About Which One You’re Giving

The biggest source of disputes is mismatched expectations. A customer who thinks they’ve received a fixed quote but was actually given an estimate will feel misled when the invoice is higher than expected — even if you were completely upfront about it at the time.

Always label your document clearly. If it’s a fixed price, write “Quotation” at the top. If it’s approximate, write “Estimate” or “Approximate Costs”. Never use one word when you mean the other.

What About Variations?

On larger jobs, it’s common for the scope to change after a quote has been agreed. Maybe the customer decides they want an extra socket adding, or you open up the floor and discover the joists need replacing.

The right approach is to issue a variation notice — a short written document that describes the additional work, the extra cost, and gets the customer to sign off before you do it. Never do extra work and surprise the customer with the cost on the final invoice. Even if the customer verbally agreed to it, without written sign-off you’re in a weak position if they dispute it later.

The Easiest Way to Get It Right

Keeping track of quotes, estimates and variations via WhatsApp messages and paper notes is how disputes happen. A proper quoting system gives you a clear, dated paper trail that protects you and reassures your customers.