Invoice vs Quote - What's the Difference?

A quote comes before the work. An invoice comes after.

Updated March 9, 2026 by invoice.Now.

Quote: A Proposed Price

A quote (also called an estimate or proposal) is a document that outlines the expected cost of a project or service before work begins. It tells the client what you plan to deliver and how much it will cost. The client can accept, negotiate, or decline the quote.

A quote is not a bill. It does not create an obligation to pay. It creates an expectation of price, which may or may not be binding depending on your agreement.

A quote typically includes:

Invoice: A Bill for Completed Work

An invoice is a formal payment request sent after work is completed (or at an agreed milestone). It states what was delivered, the amount claimed, and the deadline for payment. Unlike a quote, an invoice usually reflects work already performed under an underlying agreement.

An invoice typically includes:

Side-by-Side Comparison

QuoteInvoice
PurposePropose a priceRequest payment
Sent whenBefore work startsAfter work is done
BindingDepends on the quote terms and acceptanceDepends on the underlying agreement and applicable law
Contains due dateNoYes
Contains validity periodYesNo
Client actionAccept or declinePay by the due date

When a Quote Becomes an Invoice

The typical workflow looks like this:

  1. You send a quote outlining the scope and estimated cost.
  2. The client reviews and approves the quote.
  3. You complete the work.
  4. You send an invoice based on the approved quote.

The invoice amount may differ from the quote if the scope changed during the project. When this happens, note the changes on the invoice and reference the original quote number so the client can compare.

What About Estimates and Proposals?

The terms "quote," "estimate," and "proposal" are often used interchangeably, but there are subtle differences:

Regardless of what you call it, the key distinction remains: quotes come before work, invoices come after.

Have more questions? Check the invoicing FAQ. Ready to bill for completed work? Open the invoice editor.

Turn your quote into an invoice