Billing Basics · 02 Jun 2026 · 5 min read

What Is a Proforma Invoice? Free Template & When to Use One

Before you start a project, a client may ask "can you send a quote in invoice format?" - that's usually a proforma invoice. It looks like a real invoice but isn't a demand for payment yet; it's an estimate that shows the client exactly what they'll be charged.

What Is a Proforma Invoice?

A proforma invoice is a preliminary bill of sale sent to a buyer before goods are delivered or a service is completed. It outlines the estimated cost, quantities, and terms, giving the client a clear picture of what the final tax invoice will look like - without creating any GST liability or accounting entry yet.

Proforma Invoice vs Tax Invoice

  • Proforma invoice - an estimate or commitment to bill, not legally demanding payment, no GST filing impact.
  • Tax invoice - the final, legally binding document issued once the sale is complete, used for GST returns and input tax credit.

Never record a proforma invoice as revenue in your books - it's a quote, not a completed sale.

When Should You Send One?

  • Before starting a new project, to confirm scope and pricing with a new client.
  • For international trade, where customs or import documentation often requires a proforma invoice.
  • When a client's finance team needs a formal document to approve a purchase order internally.

What to Include in a Proforma Invoice

  • The words "Proforma Invoice" clearly labeled at the top (not "Tax Invoice").
  • Estimated item descriptions, quantities, and rates.
  • Estimated tax, if applicable, clearly marked as provisional.
  • A validity period ("Valid for 15 days") so pricing doesn't stay open-ended.

Turning a Proforma Into a Final Invoice

Once the client approves the estimate and the work is delivered, you convert it into a proper tax invoice with a new invoice number and finalized amounts. FlowInvoice's free invoice generator lets you create either version in seconds - just relabel the document and add your GSTIN once you're ready to bill for real.

Create your invoice or quote now →

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