What Is a Proforma Invoice? UK Guide + Free Template (2026)

If you've ever needed to send a customer a price commitment before a sale is final — to confirm a quote, request an advance payment, or clear goods through customs — you've needed a proforma invoice. It's one of the most misunderstood documents in UK business, mostly because it looks almost identical to a normal invoice but does a completely different job.

This guide explains exactly what a proforma invoice is, when to use one, how it differs from a standard (commercial) invoice, and the VAT rules that trip people up. There's a free template at the end.

What Is a Proforma Invoice?

A proforma invoice is a preliminary bill of sale sent to a buyer before the goods or services are supplied. It sets out what will be supplied, the agreed price, and the payment terms — but it is not a demand for payment and not a record of an actual sale.

Think of it as a formal, itemised quotation dressed as an invoice. It tells the customer: "this is exactly what you'll be charged, and on these terms, if you go ahead."

The word "proforma" (Latin: pro forma, "as a matter of form") is the giveaway — it's a formality issued in advance, not the real accounting document.

Proforma Invoice vs Invoice: The Key Difference

This is where most confusion lives. The two documents can look identical, but they are legally and accounting-wise very different.

	Proforma invoice	Commercial (tax) invoice
Sent	Before the sale is confirmed	After goods/services are supplied
Purpose	Confirm price & terms, request advance payment	Demand payment, record the sale
Legally a demand for payment?	No	Yes
Goes in your accounts?	No	Yes
Triggers a VAT point of supply?	No	Yes (creates a tax point)
Invoice number	Should not use your sequential invoice number	Uses your next sequential number

The single most important practical rule: a proforma invoice does not create a VAT tax point and should not be entered into your sales records. Only the final commercial invoice does that. (See our guide to invoice vs receipt for the related document mix-up.)

When Should You Use a Proforma Invoice?

Proforma invoices are genuinely useful in several common UK scenarios:

1. Requesting payment in advance. New customer with no credit history? Send a proforma so they can pay upfront before you start work or ship goods.
2. Confirming a quote in a formal, itemised way. It's more committal than a quote and gives the customer everything they need to raise a purchase order.
3. Letting a customer's finance team set up a payment. Many companies need an invoice-shaped document to load a supplier and schedule a payment run.
4. International shipping and customs. Proforma invoices are routinely used to declare the value of goods to customs before a commercial invoice exists.
5. Taking a deposit. Use a proforma to request a deposit, then issue a proper VAT invoice once payment is received.

If you simply want to estimate a job loosely, a quote or estimate is enough. Reach for a proforma when you want it to look and feel final.

What to Put on a UK Proforma Invoice

A proforma should contain almost everything a real invoice does, with two crucial differences: it must be clearly labelled "Proforma Invoice" and it must not use your sequential invoice number.

Include:

• The words "Proforma Invoice" prominently at the top
• Your business name, address and contact details
• The customer's name and address
• A unique proforma reference (e.g. PRO-2026-014 — kept separate from your real invoice sequence)
• The date issued
• A clear description of the goods or services
• The price per line and the total
• If you're VAT-registered: show the VAT that will apply, but make clear this is not yet a VAT invoice
• Payment terms and how to pay
• An expiry/validity date for the quoted price (recommended)

Proforma Invoices and VAT

This is the part HMRC cares about. A proforma invoice is not a VAT invoice. Your customer cannot use it to reclaim input VAT, and issuing one does not create a tax point for you.

The correct sequence for a VAT-registered business is:

1. Send the proforma to confirm the price (no tax point created).
2. The customer agrees and/or pays.
3. You issue the actual VAT invoice — this creates the tax point and goes in your VAT records.

A common compliance slip is to issue a proforma, get paid, and then forget to raise the real VAT invoice. Receiving the payment generally creates a tax point in its own right, so always follow up with the proper invoice within the required time.

If you're not VAT-registered, the mechanics are simpler — but the same labelling rule applies so the document isn't mistaken for a final bill. See how to invoice when you're not VAT registered.

Free Proforma Invoice Template (UK)

Here's a clean structure you can copy:

PROFORMA INVOICE

[Your Business Name]
[Address] · [Email] · [Phone]
[VAT No. if registered]

To: [Customer Name & Address]

Proforma Ref: PRO-2026-014        Date: 14 Jun 2026
Valid until: 28 Jun 2026

Description                     Qty     Price       Total
-------------------------------------------------------------
Website design — phase 1         1      £1,200      £1,200
Hosting setup (one-off)          1        £150        £150
-------------------------------------------------------------
                                     Subtotal:      £1,350
                                     VAT @ 20%:        £270
                                     TOTAL:         £1,620

This is a proforma invoice, not a VAT invoice or demand for payment.
Payment terms: 100% in advance. A VAT invoice will be issued on payment.
Bank: [Account name / sort code / account number]

The Fast Way: Generate One in Under a Minute

You don't need to build a proforma from scratch each time. With 1nvoic3 you can create a professional, itemised document, label it clearly, and send it — then turn it into a final VAT invoice in a couple of clicks once the customer pays. It's free, works in your browser, and needs no sign-up.

Frequently Asked Questions

Is a proforma invoice legally binding? Not as a demand for payment. It's a formal price commitment and terms offer, but it doesn't record a completed sale or oblige the customer to pay the way a real invoice does.

Can a customer pay against a proforma invoice? Yes — that's one of its main uses (advance payment). Once they pay, you should issue a proper invoice for your records.

Can I reclaim VAT using a proforma invoice? No. Only a valid VAT invoice supports an input-VAT claim. A proforma explicitly is not one.

What number should a proforma have? Use a separate reference series (e.g. PRO-…), never your sequential invoice numbers — otherwise you'll create gaps and confusion in your real invoice records. See our invoice numbering guide.

Proforma vs quote — what's the difference? A quote is an informal price estimate; a proforma is a more formal, invoice-shaped document often used to request advance payment or for customs. Functionally they overlap, but a proforma signals "this is final, here's how to pay".

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Create a proforma invoice — and the matching final invoice — in under a minute with 1nvoic3. Free, no sign-up. See also invoice vs receipt, VAT invoice requirements and our invoice numbering guide.