"Quote" and "estimate" get used interchangeably on site, but legally they are very different things — and getting them mixed up can cost you real money or land you in a dispute. Here is the plain-English difference and how to use each one properly.
What a quote actually is
A quote is a firm, fixed price to do a defined piece of work. Once the customer says yes, you have essentially agreed a contract at that price. If the job ends up taking longer than you reckoned, that is generally your risk to wear — not something you can pass on — unless the customer asks for extra work outside the original scope.
That is exactly why you should never casually call a rough number a "quote." Customers can, and do, hold you to it.
What an estimate is
An estimate is your best educated guess at the likely cost, based on what you know so far. It is not a fixed price — the final figure can move as the work unfolds and the true scope becomes clear. It suits open-ended or unpredictable jobs (think "we won't know until we open the wall up").
The trade-off: an estimate gives you flexibility but less certainty for the customer, so you need to keep them informed as the numbers move.
Why it matters legally
- A quote is binding — accepted, it is the price. Charging more without an agreed variation can breach your agreement and Australian Consumer Law.
- An estimate is not fixed — but the final price must still be reasonable, and big departures should be flagged with the customer, not sprung on them at invoice time.
- Label it clearly — write "Quote" or "Estimate" on the document so there is zero ambiguity about whether the price is locked in.
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Open the free toolWhich should you give?
- Give a quote when the job is well-defined and you can scope it confidently. Customers love the certainty and it looks professional — just pad your hours for the unexpected.
- Give an estimate when the work is genuinely open-ended and you cannot pin the scope down yet. Be upfront that it is an estimate and explain what could move the price.
Either way, the winning move is the same: get it out fast, make it clear, and label it correctly.
Frequently asked questions
A quote is a fixed price you commit to — once the customer accepts it, that is generally the price, even if the job takes longer than you thought. An estimate is your best educated guess of the likely cost, which can change as the work unfolds. The key difference is that a quote is binding; an estimate is not.
Generally yes. Once a customer accepts your quote, it usually forms a binding agreement to do the work for that price. You can only charge more if the scope genuinely changes and you agree a variation with the customer first. This is exactly why you should never label a rough figure a “quote.”
Yes, within reason — an estimate is not a fixed price, so the final cost can differ. But you should keep the customer informed as costs move and not blow wildly past the figure without warning. Under Australian Consumer Law the final price still needs to be reasonable and any variations communicated.
Give a quote for well-defined jobs where you can scope the work confidently — customers prefer the certainty and it looks professional. Use an estimate for open-ended or unpredictable work where the scope genuinely cannot be pinned down yet. Whichever you give, label it clearly so there is no confusion about whether the price is fixed.
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