Written by Bryant Gan, Founder, Niagawan · Last updated 24 July 2026
The short answer: a proforma invoice is a preliminary document you send before a sale is confirmed — an estimate the buyer reviews and approves. An invoice is the actual bill you issue after the sale is agreed; it records the transaction, requests payment, and — in Malaysia — becomes the tax document. Same-looking layout, completely different job: one proposes a deal, the other records it.
A proforma asks “shall we go ahead?”; an invoice says “here’s what you owe.”
Everything below is the detail behind that difference — including the part the global guides miss, which is what it means for SST and LHDN e-invoice in Malaysia. New to the document itself? Start with our full proforma invoice guide, then come back here for the comparison.
01. Proforma invoice vs invoice — side by side
This is the comparison most people are actually searching for. The two documents can look almost identical on the page, but they do opposite jobs. Here is the full side-by-side:
| Proforma invoice | Invoice (tax invoice) | |
|---|---|---|
| Purpose | Preview of a proposed sale | Bill for a confirmed sale |
| When issued | Before the sale is finalised | After the sale is agreed |
| Legally binding? | No — it's an estimate | Yes — it's a demand for payment |
| Triggers payment? | Not officially (buyer may pay to confirm) | Yes — it's the request to pay |
| Recorded in your accounts? | No — not a real transaction yet | Yes — it becomes accounts receivable |
| A tax / SST document? | No | Yes — this is the document that carries tax |
| Can it be changed? | Yes — quantities and prices can still move | No — changes need a credit note |
| Number | Often a temporary/proforma reference | A permanent, sequential invoice number |
The single most important row is the tax one: only the invoice is a tax document. A proforma cannot account for tax and cannot support a tax claim. Hold that thought — in Malaysia it decides which document you're actually allowed to use.
02. When do you send which?
The rule is about timing, not format:
The buyer is interested but the deal isn't locked — they need a formal figure to approve internally, arrange payment, apply for financing, or clear customs. Nothing is committed yet.
The sale is confirmed — the goods or services are agreed and it's time to bill. This is the document that goes into your books and asks for payment.
A common, healthy flow is: quotation → proforma invoice → invoice. You quote a price, the buyer asks for a formal proforma to approve, and once they say yes you convert it into the real invoice.
03. The Malaysia difference: SST & e-invoice
This is where a proforma and an invoice stop being interchangeable — and where the international guides don't help a Malaysian business.
A proforma invoice is not a valid tax document. It cannot account for SST, and your buyer cannot use it to claim anything. It's a proposal, so tax has no place on it yet.
Once the sale is confirmed, the proper document is the e-invoice — the LHDN-compliant tax invoice. This is an ongoing requirement Malaysian businesses are moving to, and it's the document that carries SST (where it applies to your goods or services) and is recognised for tax purposes. In short:
- No SST accounted for
- Not submitted to LHDN
- An estimate the buyer approves
- SST applied where applicable
- LHDN-compliant
- The real, recorded transaction
So the practical sequence for a Malaysian SME is: send the proforma to get the “yes,” then issue the LHDN-compliant tax invoice as the real, compliant bill. Skipping straight from a proforma to “paid” — with no proper tax invoice behind it — is the mistake that causes trouble later.
04. Proforma invoice vs the other documents it gets confused with
A proforma sits in a crowded field of pre-sale paperwork. Here's how it differs from the four documents it's most often mixed up with:
A quotation is an informal price offer, usually earlier and looser. A proforma is a more formal, itemised version — closer to what the final invoice will look like — that the buyer treats as something to approve. Quotation = “roughly this much”; proforma = “exactly this, if you agree.”
A commercial invoice is used in international shipping and customs to declare the actual value of goods being exported. A proforma may travel with a shipment before the sale, but the commercial invoice is the real, final document customs relies on.
A purchase order comes from the buyer — it's their formal request to buy. A proforma comes from the seller — it's your formal offer to sell. They often cross paths in the same deal, from opposite sides.
A sales order is your internal confirmation that you'll fulfil the deal once accepted. The proforma is the outward-facing document you send the buyer; the sales order is what kicks off fulfilment on your end.
05. A worked example: the same deal, before and after
Say a buyer wants 10 office chairs at RM150 each. Here's the same deal as two different documents. (Figures are illustrative.)
Notice what changed: the numbers for the goods are identical, but the status, the tax treatment, and the legal weight are completely different. That's the whole point.
06. Common mistakes to avoid
A few small mistakes cause most of the trouble around proforma invoices. Watch for these:
Turn an approved proforma into a compliant e-invoice without retyping
- Issue proforma-style documents and quotations to win the “yes”
- Convert an approved proforma into an LHDN-ready e-invoice — same system
- One transparent yearly price, no consultant and no setup fee
07. How Niagawan handles both
With Niagawan, you can issue proforma-style documents and quotations to win the “yes,” then convert an approved proforma into a proper, e-invoice-ready tax invoice without re-keying the details. That means the pre-sale document and the compliant e-invoice stay connected — so nothing gets lost between “shall we go ahead?” and “here's your bill.”
Niagawan is cloud accounting and invoicing built for Malaysian SMEs. Over 40,000 Malaysian businesses have used it since 2016 (4.7★ from 500+ Google reviews). If you're setting up your invoicing flow, the full proforma invoice guide walks through the document itself, with a free Malaysia proforma template you can download and fill in today.
Frequently asked questions
Can a proforma invoice be paid?
A buyer can choose to pay against a proforma to confirm the order, but it isn't an official request for payment and it isn't a receipt. You should still issue a proper invoice for the confirmed sale.
Can a proforma invoice be used as an invoice?
No. A proforma is an estimate, not a tax document. It can't be recorded as a sale or used for a tax claim — you must issue a real invoice (in Malaysia, an e-invoice) once the deal is confirmed.
What are the risks of using a proforma invoice?
The main risk is treating it as final: no valid tax document, nothing properly recorded in your accounts, and no SST accounted for. Used correctly — as a pre-sale offer that you later convert — a proforma is perfectly safe.
Is a proforma invoice the final invoice?
No. It's the step before the final invoice. The final, binding document is the invoice (tax invoice / e-invoice) you issue after the sale is agreed.