Proforma Invoice vs Tax Invoice — When to Use Which
Proforma vs tax invoice: what's the difference, when to use which, and how to avoid costly mistakes.
A proforma invoice is not a real invoice. It’s a quote dressed in invoice clothing.
That single distinction trips up freelancers, importers, and small business owners every day. Get it wrong and you either create a tax liability you didn’t intend or hand customs a document they’ll reject. Here’s how to tell the two apart and pick the right one.
What is a proforma invoice?
A proforma invoice is a preliminary document that confirms pricing, quantities, and terms before a deal is finalized. Think of it as a formal price offer. The seller sends it so the buyer knows exactly what they’ll pay — nothing more.
It creates no obligation to pay. It triggers no VAT. Your accountant doesn’t record it in the books. The word “proforma” literally means “for the sake of form.”
Buyers use proformas to get internal purchase approvals, arrange financing, or clear goods through customs before the actual shipment arrives.
What is a tax invoice?
A tax invoice is a legal document. Once you issue one, three things happen: the buyer owes you money, VAT becomes due to the tax authority, and both parties must record the transaction in their accounting.
Tax invoices carry mandatory elements — sequential numbering, your tax ID, the buyer’s tax ID (for B2B), applicable VAT rates, and the total amount due. Skip any of these and the document may be invalid.
In most jurisdictions, you cannot claim a VAT deduction without a properly issued tax invoice. That’s why tax authorities care about them and don’t care about proformas.
Key differences
| Proforma Invoice | Tax Invoice | |
|---|---|---|
| Purpose | Quote / estimate | Payment request |
| Legal status | Not binding | Legally binding |
| VAT liability | No | Yes |
| Accounting | Not recorded | Must be recorded |
| Numbering | Optional | Mandatory sequential |
| Can claim VAT? | No | Yes |
The table looks simple but the consequences are not. Issue a tax invoice too early and you owe VAT before you’ve been paid. Use a proforma where a tax invoice is required and your client can’t deduct their VAT.
When to use a proforma
Customs and imports. Shipping goods internationally? Customs authorities need a proforma to assess duties before the shipment clears. The document describes what’s in the crate, its value, and its country of origin. Without it, your container sits at the port.
Large projects before taking a deposit. A web agency quoting a €30,000 redesign sends a proforma first. The client reviews the scope, gets budget approval from their CFO, then asks for the real invoice. Jumping straight to a tax invoice creates awkward corrections if the scope changes.
New clients who want pricing first. You’ve never worked with this buyer. They want to see exactly what they’ll be charged before committing. A proforma gives them that clarity without locking either side into a transaction.
Cross-border B2B sales. When selling to a business in another country, the buyer often needs a proforma to arrange payment through their bank, especially with letters of credit or advance wire transfers.
When to convert proforma to invoice
The proforma’s job ends once the deal moves forward. Convert it to a tax invoice when:
- Goods have shipped. The product left your warehouse — issue the tax invoice.
- Service has been delivered. You finished the project milestone — time to bill.
- Payment is due per agreed terms. The contract says “payment within 14 days of acceptance” and the client accepted.
Don’t let proformas linger. A proforma sitting in someone’s inbox for three months isn’t a receivable — it’s a forgotten quote.
Common mistake: using a proforma as a tax document
Some businesses issue proformas to delay VAT obligations while still expecting payment. Tax authorities see through this. If a document requests payment and looks like an invoice, inspectors may reclassify it as a tax invoice regardless of what you’ve printed at the top.
The reverse is also a problem. Handing your client a proforma when they need a tax invoice means they can’t deduct VAT on their end. That makes you harder to do business with.
Rule of thumb: if money is changing hands, issue a tax invoice. If you’re still negotiating, use a proforma.
Create both in minutes
Start with our Quote Generator to build a professional proforma invoice. Once your client confirms, convert it to a proper tax invoice with the Invoice Generator — same line items, correct numbering, VAT calculated automatically.