Pro Forma vs Commercial vs Tax Invoice: What's the Difference?

There are at least a dozen different things called "invoice" in business writing, and the three that confuse people most are pro forma invoice, commercial invoice, and tax invoice. They look similar at first glance. The fields overlap. The names suggest small variations. But they're three genuinely different documents with three different jobs, and using the wrong one can cost you a customs delay, a missed VAT reclaim, or an awkward conversation with a tax auditor.

This guide explains each one in plain English: what it is, when to send it, what fields it must contain, and what happens if you confuse them. With real-world examples for freelancers, small businesses, and anyone selling across borders.

The three invoices at a glance

Before going deeper, here's the quick differentiator:

	Pro Forma Invoice	Commercial Invoice	Tax Invoice
When	BEFORE the sale	AT THE SALE (export/customs)	AT or AFTER the sale
Purpose	Quote / confirmation of terms	Customs declaration	Request payment + tax record
Legally binding	No	Yes (for customs)	Yes (for tax authority)
Goes in your books	No	Yes (cost of sale)	Yes (revenue + tax)
Tax claimable	No	Sometimes	Yes (input tax credit)
Customer pays from it	Sometimes	Usually	Always

Each one fits a different stage of a sale. None of them is a "better" version of the others. They serve different needs.

For the basics of any invoice (which apply to all three), see our complete guide on how to make an invoice.

What is a pro forma invoice?

A pro forma invoice is a document a seller sends to a buyer BEFORE a sale is finalised, confirming the proposed terms. The Latin "pro forma" means "for the sake of form". The document looks like an invoice but isn't one yet.

You'd use a pro forma invoice to:

• Confirm a price quote in formal writing
• Give a buyer something to take to their internal procurement or finance team for approval
• Support an import licence or letter-of-credit application
• Lock in an exchange rate or quoted price for a fixed period

A pro forma includes most of the same fields as a real invoice (seller, buyer, items, prices, totals), but with three key differences:

1. The word "Pro Forma" or "Pro Forma Invoice" must be visible at the top, usually replacing the word "Invoice"
2. No invoice number from your real sequence. Use a separate "PF-001" sequence or label it "Pro Forma No. 001". A pro forma is NOT part of your tax-invoice numbering chain.
3. No tax registration number treated as a tax invoice. Including your VAT or GST number is fine for context, but the pro forma should not be entered into the buyer's input-tax claim.

What it's NOT:

• It is NOT a request for payment in the legal sense.
• It is NOT proof of supply for VAT or GST purposes.
• It does NOT go in your sales ledger as revenue.

A pro forma converts to a real invoice once the buyer commits to the sale. At that point, you issue a fresh tax invoice with a real invoice number from your sequence and the pro forma gets archived.

For the structure of your real invoice number (which the pro forma should NOT use), see our invoice numbering guide.

What is a commercial invoice?

A commercial invoice is a document used in international trade to declare the contents and value of a shipment to customs authorities. It's the primary document customs officials use to calculate import duties, taxes, and clearance fees.

If you've ever shipped something internationally via DHL, FedEx, UPS, or post, you've encountered a commercial invoice, usually attached to the parcel in a plastic pouch.

A commercial invoice typically includes:

• Seller's name, address, and tax/business registration number
• Buyer's name, address, and tax registration if applicable
• Detailed description of every item: what it is, what it's made of, country of origin
• HS codes (Harmonized System) for each line
• Unit value, total value, currency
• Shipping terms (Incoterms: FOB, CIF, DDP, etc.)
• Reason for export (sale, gift, sample, return)
• Signature of the exporter

The key difference from a regular invoice: a commercial invoice describes the goods in the level of detail customs needs, not just the level of detail your buyer's accounts payable team needs. "Web design services, $2,400" is fine for a domestic services invoice. For physical goods crossing borders, you need item-level descriptions with HS codes.

Who needs to issue one:

• Any business shipping physical goods internationally
• Some service exports under specific country rules (rare)
• Returns, samples, and gifts also require a commercial invoice, with the reason for export noted

For a pure service business invoicing international clients, a commercial invoice usually isn't relevant. A standard tax invoice covers the transaction. See our international clients guide for the services version of cross-border invoicing.

Customs gotcha: declared value matters. Undervaluing a commercial invoice to save the buyer duty is illegal in every jurisdiction and triggers a hold on the shipment if discovered.

What is a tax invoice?

A tax invoice is the legally significant version of an invoice for any business registered for VAT, GST, or equivalent indirect tax. It's the document that:

• Establishes the supplier's liability for output tax on the sale
• Lets the buyer claim back input tax (where they're registered)
• Forms part of both parties' tax records for audit

Every tax authority has its own rules for what a tax invoice must contain. The patterns are similar across countries:

Required on a tax invoice almost everywhere:

• The words "Tax Invoice" or equivalent visible on the document
• A sequential, unique invoice number
• Issue date (and supply date if different)
• Seller's name, address, and tax registration number (VAT, GST, GSTIN, etc.)
• Buyer's name and address; their tax registration number if registered
• Description of each line of goods or services
• Quantity, unit price, line total
• Subtotal, tax rate(s), tax amount(s), and grand total

Country-specific extras to be aware of:

• United Kingdom (HMRC). "Tax Invoice" wording, the supplier's VAT number, and the tax point (date the supply was made or invoiced). See the UK invoice guide.
• EU member states. Sequential numbering plus the buyer's VAT number for B2B intra-community supplies (so reverse charge can apply). See our Ireland guide.
• Australia (ATO). "Tax Invoice" wording, ABN, GST amount shown separately. See the Australia guide.
• India (CGST Rule 46). Sequential invoice number under 16 chars, GSTIN, HSN/SAC codes, place of supply, CGST + SGST split or IGST. See the India guide.
• Singapore (IRAS). "Tax Invoice" wording, GST number, GST amount shown. See the Singapore guide.
• South Africa (SARS). Full tax invoice for supplies above R5,000 (with serial number, supplier's VAT vendor number, etc.); abridged tax invoice for smaller supplies. See the South Africa guide.

The tax invoice is what tax authorities care about. The pro forma is internal. The commercial invoice serves customs. The tax invoice serves the tax man.

When to use which

A typical export sale that involves all three:

1. Buyer asks for a price. You send a pro forma invoice with proposed terms, a quoted price, and a validity window.
2. Buyer's procurement team approves. They issue a purchase order against the pro forma.
3. You ship the goods internationally. A commercial invoice travels with the shipment for customs.
4. You issue the actual sale document. A tax invoice is your formal request for payment and goes in both parties' books.

For pure service businesses (freelancers, consultants, agencies) selling domestically, the simpler workflow is:

1. Quote (a less formal email or pro forma)
2. Tax invoice when work is done

For service exporters, you usually skip the commercial invoice and go straight from quote / pro forma to tax invoice.

Common confusions resolved

"Can I use a pro forma as a real invoice if the buyer paid against it?" No. Issue a fresh tax invoice with a real invoice number. The pro forma was a quote; once payment hits, you need a proper tax invoice for both your records and the buyer's.

"Is a commercial invoice also a tax invoice?" Sometimes. For domestic supplies, no — the commercial invoice doesn't include the tax-invoice fields some jurisdictions require. For international shipments, the commercial invoice can double as the tax invoice if it includes all the tax-authority-required fields. Most exporters issue both, to avoid ambiguity.

"What about a regular invoice — is that a tax invoice?" If you're VAT or GST registered and the invoice includes your tax registration number, the tax amount shown separately, and the word "Tax Invoice" (or equivalent), then yes. If any of those are missing, it's just an "invoice" and may not qualify for the buyer's input-tax claim.

"Do I need a tax invoice if I'm not VAT/GST registered?" No. A registered business below the registration threshold issues simple "invoices" without tax. These are still legally binding requests for payment but don't carry the tax-invoice status.

"What about a credit note?" A credit note is a separate document type from all three above. It's issued by the seller to reduce a previous invoice (correcting an overcharge, processing a return, etc.). It has its own number sequence and references the original invoice. Don't confuse it with a pro forma.

For more on credit notes and the related "what is an invoice" question, see our invoice vs receipt vs bill guide.

What happens if you use the wrong one?

Real-world consequences of getting the wrong invoice type:

1. Pro forma treated as a tax invoice. The buyer claims input-tax credit on a document that wasn't a valid tax invoice. Tax authority disallows the claim. The buyer is unhappy with you.
2. Pro forma used as a commercial invoice. Customs at the destination flags the shipment because the values look provisional. Delivery delayed by days or weeks.
3. Commercial invoice missing customs fields (HS codes, country of origin). Same as above. Customs holds the shipment for documentation.
4. Tax invoice missing the tax registration number. Buyer can't claim input-tax credit. Either you reissue or they swallow the cost.
5. Tax invoice with a different number sequence than your real one. Tax authority audit shows non-sequential numbering. Penalty possible in some jurisdictions.
6. Undervaluing a commercial invoice. Customs caught it. Penalties, possible blacklisting, and your shipping account flagged.

The pattern: tax authorities and customs authorities both care that you used the right document. Mixing them up looks careless at best and fraudulent at worst.

Make any of the three with Invoicara

Invoicara's free invoice generator is designed for the tax-invoice case (the most common one for small businesses and freelancers). The same form can be used for pro forma invoices by labelling the document "Pro Forma" in the notes section and using a separate PF-prefix number outside your real sequence.

For commercial invoices used in international physical-goods exports, you'll usually need a customs-broker template or a dedicated tool that captures HS codes. Invoicara is the right tool for everything else: standard tax invoices, multi-currency, multi-tax, freelance work, consulting, SaaS, services, and small-business B2B.

For the structure of every invoice number, see our invoice numbering guide. For the layout that applies to all three invoice types, see our invoice format and layout guide. And for the broader question of when an invoice is or isn't an invoice, our invoice vs receipt vs bill guide clears up the terminology.

Three invoice types, three jobs. Pro forma for the quote stage, commercial for the border, tax for the books. Use each one for what it's designed for and you'll spend zero time arguing with customs, accountants, or auditors.