What is the difference between an estimate, a quote and an invoice?

An estimate gives an approximate price, a quote offers a price for specified work, and an invoice requests payment. The first two help describe a proposed purchase; the invoice asks the customer to pay an amount. The document’s conditions still matter.

Compare their jobs

Document	Usual purpose	What to look for
Estimate	Indicate the likely cost before all details are settled	Assumptions, range and possible changes
Quote	Offer a price for a defined scope	Included work, exclusions, validity and acceptance terms
Invoice	Request payment for identified goods or services	Description, amount, due date and payment terms

For a concrete jurisdictional reference, New Zealand’s Commerce Commission explains estimates, quotes and invoicing. Its guidance treats an estimate as an approximation based on reasonable assumptions, and an accepted quote as an agreement to perform the quoted work at that price. It says extra work outside the quote needs customer agreement to a changed price. Those are New Zealand guidance points, not a universal rule inferred from a heading on a document.

An illustrative sequence

Suppose someone wants a damaged noticeboard repaired. Before inspecting it, the repairer estimates 100–140 currency units. After agreeing the materials and work, the repairer quotes 120 units for that scope. The customer accepts. The later invoice requests the agreed 120 units.

These invented amounts show the different roles; they are not market prices or tax calculations. If the customer then requests another repair, its scope and price need to be addressed rather than silently treating the original quote as covering it.

Conditions that matter

• Read the scope and assumptions. Similar-looking documents can contain different pricing conditions. An estimate is not permission to add any amount without explanation.
• Distinguish a request from proof of payment. An invoice is not a receipt. GOV.UK makes that distinction in its invoicing guidance.
• Check the applicable rules. Required invoice details, tax treatment and the contractual effect of a quote depend on the jurisdiction and agreement. A document title alone does not resolve a disputed charge.

Source guidance checked on 21 October 2026. The example above is illustrative; this card explains document roles rather than supplying jurisdiction-specific invoice wording.