Invoice vs Tax Invoice: What's the Difference?
A plain invoice is simply a request for payment. A tax invoice is a specific GST document that lets a registered buyer claim back the GST on the sale.
In this answer
- Tell a plain invoice apart from a tax invoice
- Understand why GST registration drives the choice
- Know what a buyer loses if they get the wrong one
- Decide which document fits your business
4 min
Two documents, two jobs
The terms get used interchangeably, but they are not the same. A plain invoice is a request for payment — it lists what you supplied and what is owed. It has no fixed legal form. A tax invoice is a GST document with specific required fields, and it is the piece of paper a GST-registered buyer needs in order to claim back the GST they paid you.
Put simply: every tax invoice is an invoice, but not every invoice is a tax invoice. The difference matters most for the buyer, because their ability to claim a GST credit hangs on receiving a valid tax invoice rather than a plain one.
What decides which you issue
The deciding factor is usually whether you are registered for GST. If you are registered and making a taxable sale, you generally issue a tax invoice. If you are not registered, you do not charge GST and you issue a plain invoice instead — there is no GST for the buyer to claim, so a tax invoice would not be appropriate.
Whether you must be registered depends on your turnover and circumstances, and the registration test is set by the ATO. Because the threshold is indexed and your situation can change, confirm your registration position with the ATO or your accountant rather than assuming.
What a tax invoice adds
Compared with a plain invoice, a tax invoice carries extra detail: the words 'tax invoice', the seller's ABN, and a clear statement of how GST applies — either the GST amount or a note that the price includes GST. Those additions are exactly what the buyer's accounts team looks for. A plain invoice that simply says 'invoice' and shows a total is fine for a customer who cannot claim GST, but it will not support a GST credit. If you are registered, default to issuing a tax invoice so your customers are never short of what they need.
Which should you use?
If you are GST-registered, issue tax invoices as standard. If you are not, a clear plain invoice is enough. Our free invoice tools can produce either, and invoicing without GST registration is covered separately.
This is general information only, not tax or legal advice. GST registration and invoicing rules depend on your circumstances — confirm them with the ATO or your accountant before relying on them.
Key takeaways
- A plain invoice requests payment; a tax invoice is a GST document.
- GST registration usually decides which one you issue.
- Only a valid tax invoice lets a registered buyer claim GST.
- If you are registered, issue tax invoices by default.
- Confirm your registration position with the ATO or your accountant.
Frequently asked questions
Can I call a plain invoice a 'tax invoice'?
Only if it actually meets the tax-invoice requirements. Labelling a document 'tax invoice' without the required GST detail can mislead your customer. Confirm the requirements with the ATO or your accountant.
If I'm not registered for GST, what do I issue?
A plain invoice with no GST. You should still show your ABN. See our answer on invoicing without GST registration for the detail.
Does the buyer care which one they get?
Yes, if they are registered for GST — they need a valid tax invoice to claim the credit on the purchase.
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