Pro forma invoice vs. invoice: what's the difference?

A client asks for a “pro forma invoice” before they’ll commit. Is that the same as a normal invoice? Not quite — and sending the wrong one can mess up both sides’ books.

The short answer

• A pro forma invoice is a preview of what you intend to charge, sent before the work or delivery is confirmed. It’s not a demand for payment and shouldn’t be entered as a payable in the client’s accounts.
• A (commercial) invoice is the real thing — a formal request for payment, issued once the goods or services are agreed or delivered. This is what gets recorded and paid.

Think of the pro forma as “here’s what it will cost”, and the invoice as “here’s what you now owe”.

When to use a pro forma

• The client needs a document to approve internally or raise a purchase order against before you start.
• They want to arrange payment or financing in advance.
• For cross-border shipments, customs may want an estimated value up front.

It’s close to a quote, but formatted like an invoice — which is why clients in more formal procurement processes ask for one.

How a pro forma differs in practice

• It should be clearly labelled “Pro forma” so nobody mistakes it for a payable.
• It typically doesn’t carry a sequential invoice number from your real invoice run (or uses a separate series), so your numbering stays clean — see invoice numbering best practices.
• Amounts can still change before the final invoice; a real invoice is fixed.

What a pro forma should include

Much the same as an invoice — your details, the client’s, an itemised breakdown, totals, and expected payment terms — just marked as pro forma and, ideally, with a validity date.

Issue the real invoice when it’s time

Once the work is agreed or delivered, send the actual invoice. The invoice generator produces a proper numbered invoice as a PDF; for the preview stage, the quote template covers most pro forma needs.

Keep the real ones moving

Pro formas don’t get chased — invoices do. Once you’ve issued the real invoice, Duefy tracks it and follows up automatically if it goes overdue, so the document that actually owes you money never slips through.