Quote vs estimate — what's the difference?

People use “quote” and “estimate” interchangeably, but they mean different things — and the difference matters if a customer disputes the final bill.

The short answer

• A quote is a fixed price you commit to for clearly described work. Once accepted, it’s generally the agreed price.
• An estimate is your best approximation of the cost — useful when the scope isn’t fully known. It can change as the work becomes clearer.

Side by side

	Quote	Estimate
Price	Fixed	Approximate
Binding once accepted?	Generally yes	No
Best when	Scope is clear	Scope is uncertain
Can change?	Only by agreement	Yes, with good reason

When to use each

Give a quote when you can see exactly what’s involved and can commit to a price — most fixed-scope jobs. Give an estimate when there are unknowns (you won’t know until you start), and say clearly that it’s an approximation and what could change it.

Whichever you send, label it clearly so the customer knows what they’re looking at, and include a valid-until date so it doesn’t stay open forever.

Turning a quote into an invoice

When the customer accepts, you don’t start again. Keep the same details and line items and issue an invoice with a fresh invoice number. In the generator, create a Quote, then use Convert to invoice — it carries everything over and assigns a new invoice number. For more, see quotes and estimates.