Invoice vs Quote vs Estimate vs Receipt vs Proforma: When to Use Each

These five documents look similar but do different jobs. Quote: fixed price before work. Estimate: approximate price before work. Invoice: requests payment after work. Receipt: proves payment was made. Proforma: preview invoice for approval before work.

The five documents, side by side

Quote — You promise a fixed price. The client accepts, you do the work for that amount. Has an expiry date (usually 14–30 days). Use when the scope is clear and you can commit. Try the free quote generator.

Estimate — You suggest an approximate price. It can change once the scope is clear. Not binding. Use when the job is uncertain — trades, custom work, discovery phases. Try the free estimate generator.

Invoice — You request payment for work done. Lists what was delivered, the amount owed, and when to pay. This is the document that gets you paid. Try the free invoice generator.

Receipt — You confirm payment was received. Sent after payment, not before. Includes the date, amount, and method. Try the free receipt generator.

Proforma invoice — A preview of the final invoice, sent before work for the client’s internal approval. Not a demand for payment. Common in international trade and large B2B deals.

Which document do you need?

  • Client asks “roughly how much?” → Estimate
  • Client asks “what’s the exact price?” → Quote
  • Work is done, time to get paid → Invoice
  • Client paid, they want proof → Receipt
  • Client needs approval before you start → Proforma

The document chain

For larger jobs, the documents form a chain: Estimate (rough idea) → Quote (firm offer) → Client accepts → Work → Invoice (request payment) → Client pays → Receipt (proof). Each step is evidence if there’s a dispute. Skip the written acceptance and you have a gap exactly where disputes form.

Common mistake: Sending an invoice before the client agreed to a price. It reads as presumptuous. Send a quote or estimate first, get approval in writing, then invoice.

All four generators are free with no signup: quote, estimate, invoice, receipt. For payment terms, see invoice payment terms explained.

Last checked: October 2026. By Innvoic.