If your business is registered for GST, you must give a customer a compliant tax invoice within 28 days of them asking for any taxable sale over $82.50, including GST. If you get the details wrong, your client cannot claim their GST credit, which quickly becomes your problem too. Meeting the tax invoice requirements Australia enforces is not complicated once you know the rules, but the details still matter.
This guide breaks down exactly what your invoices need in 2026, whether you run a small business, contract independently, or consult.
What Is a Tax Invoice?
A tax invoice is the document that includes GST and specific details the ATO requires. It lets your GST-registered clients claim back the GST they paid you.
Here is the key distinction. A tax invoice is only for GST-registered businesses, and it shows the GST charged. If you are not registered for GST, you issue a plain “invoice” instead, with no GST and without the words “tax invoice”. Using the right document is the first rule of compliant invoicing, whether you handle it by hand or through contracting and invoicing software.
What Must a Tax Invoice Include?
For taxable sales under $1,000, the ATO requires seven specific details. Miss any one and the invoice may not be valid.
Your tax invoice must clearly show:
- The words “tax invoice”, stated prominently
- Your business or trading name
- Your Australian Business Number (ABN)
- The date the invoice was issued
- A brief description of what was sold, including quantity and price
- The GST amount, or a statement that the total price includes GST
- Which items on the invoice are taxable
These seven fields are the baseline for meeting the ATO invoice requirements. They apply to every taxable sale you make once you are registered.
What Changes for Sales of $1,000 or More?
Once a sale hits $1,000 or more including GST, one extra detail becomes mandatory. You must also show the buyer’s identity or their ABN.
For anything under $1,000, your own details and a clear description are enough. Above that line, the buyer’s name or ABN is required so their accounts team can match the invoice to their records. This is a common trip-up for larger contracts, and getting the GST invoice requirements right on high-value work avoids delays. A big invoice missing the buyer’s details can sit unpaid while they ask you to reissue it.
How Do You Show GST on an Invoice?
There are two accepted ways to display GST, and either is fine. The choice is yours, as long as it is clear.
You can show the GST amount separately for each line item, or you can state that the total price includes GST. Both satisfy the ATO. The one rule to remember is that you only charge GST and use the label “tax invoice” if you are actually registered. Showing GST on invoices when you are not registered is a genuine compliance problem, so stick to a plain invoice until you register.
How Do You Write a Compliant Invoice?
Putting it all together is straightforward once you know the pieces. A compliant invoice follows a simple, repeatable structure.
Here is how to write one that ticks every box:
- Head the document “Tax Invoice” clearly at the top
- Add your business name and ABN
- Include the issue date & an invoice number
- List each service or item with a description and price
- Show the GST, either per line or as a total-includes-GST note
- Add the buyer’s details if the sale is $1,000 or more
- State your payment terms and due date
A clear tax invoice example always separates the item amounts from the GST, so both you and your client can see exactly what was charged.
Once you have this structure, knowing how to write an invoice becomes second nature, whether you type it up or use invoicing and online payment tools to generate it automatically.
What About Record-Keeping and the 28-Day Rule?
Two ATO rules catch people out, and both are easy to follow. They protect you if your records are ever checked.
First, the 28-day rule. If a client asks for a tax invoice, you must provide it within 28 days of their request. Second, record-keeping: you must keep copies of your tax invoices for at least five years. Electronic copies are perfectly valid, so a well-organised digital system makes this effortless.
Do Sole Traders Have Different Requirements?
Sole traders follow the same rules, with one important warning about the ABN. Your ABN is not optional on invoices to business clients.
If you leave your ABN off, a business client is legally required to withhold 47% of your payment for the ATO. That single omission can cost you nearly half your money until tax time. So whether you use a sole trader invoice template or generate invoices through software, your ABN must appear every time. Any decent invoice template Australia businesses rely on will have a dedicated spot for it, precisely because it matters so much.
Make Compliant Invoicing Effortless
Getting your invoices right protects your cash flow and keeps you on the right side of the ATO. The rules are clear: use the correct document, include the seven details, add buyer details past $1,000, and keep your records for five years.
Doing all this by hand, on every invoice, is where errors creep in. This is where Gemma helps. Instead of filling in an invoice template Australia businesses download and complete manually, Gemma generates professional, ATO-compliant tax invoices automatically, applying your ABN and GST correctly every time, with secure online payment built in. If manual invoicing is slowing you down, explore Gemma and let compliant invoicing take care of itself. See more
Frequently Asked Questions
What happens if my invoice is missing a required detail?
Your client may be unable to claim their GST credit, and they can ask you to reissue it. For a missing ABN, a business client must withhold 47% of your payment.
Do I need to issue a tax invoice for small sales?
Not for taxable sales of $82.50 or less, unless the customer requests one. Above that amount, you must provide a tax invoice within 28 days if asked.
Can I send tax invoices electronically?
Yes. Electronic tax invoices, including PDFs and software-generated ones, are fully valid under ATO rules, provided they contain all the required details.
Do I charge GST if I’m not registered?
No. You must never charge GST or label a document a “tax invoice” unless you are registered. Issue a plain invoice instead, but always include your ABN.