How to Create a GST Invoice in Australia (Free Template)

Published April 2026 • 8 min read

If you run a business in Australia and are registered for GST, issuing correct tax invoices is not optional -- it is a legal requirement. A GST-compliant invoice ensures your customers can claim input tax credits, keeps you on the right side of the ATO, and makes BAS lodgement far less painful.

Yet many small business owners get the details wrong, risking penalties and delayed payments. This guide walks you through exactly what a GST invoice must contain, the difference between a standard and simplified tax invoice, and how to connect your invoicing to BAS reporting. There is also a free template you can start using immediately.

What Is a GST Invoice?

A GST invoice -- formally called a "tax invoice" by the ATO -- is a document that records a taxable sale and shows the amount of GST included in the price. It serves two critical purposes: it tells the buyer exactly how much GST they paid, and it acts as documentary evidence for both parties when reporting GST on their Business Activity Statements.

Under Australian tax law, you must issue a tax invoice within 28 days of a request from the buyer. In practice, most businesses issue one at the point of sale or when the work is completed. Without a valid tax invoice, your customers cannot claim input tax credits for GST they have paid -- which means business clients will chase you for a compliant document, or simply stop buying from you.

Who Needs to Issue Tax Invoices?

You must issue tax invoices if your business is registered for GST (mandatory once your annual turnover reaches $75,000, or $150,000 for non-profit organisations). Even if you voluntarily register below the threshold, the same rules apply.

There are a few situations where a tax invoice is not required:

• Sales under $82.50 (including GST): For these low-value transactions, a regular receipt or docket is sufficient, though many businesses issue a tax invoice anyway for consistency
• GST-free supplies: Items like basic food, certain medical services, and exports do not attract GST, so no tax invoice is needed
• Input-taxed supplies: Financial supplies and residential rent are input-taxed and do not require a tax invoice

Standard vs Simplified Tax Invoice

The ATO recognises two types of tax invoices, and the one you use depends on the value of the sale:

Simplified Tax Invoice (sales of $1,000 or less including GST)

A simplified tax invoice has fewer requirements and is suitable for most everyday retail and service transactions. It must include:

• The seller's identity (business name) and ABN
• The date of issue
• A brief description of each item sold
• The total price including GST
• A statement that the total includes GST (or show the GST amount separately)

Standard Tax Invoice (sales over $1,000 including GST)

For higher-value transactions, a standard tax invoice must include everything on a simplified invoice plus:

• The word "Tax Invoice" stated prominently
• The buyer's identity (name or ABN)
• The quantity of each item or the extent of each service
• The GST amount for each line item, or a statement that the total price includes GST

Most accounting and invoicing software -- including free tools like BizziKit Invoice Builder -- automatically includes all required fields regardless of the sale amount, so you rarely need to think about which format applies.

Mandatory Elements of a Tax Invoice

To be ATO-compliant, every standard tax invoice must contain these elements:

1. The words "Tax Invoice": Clearly displayed at the top of the document so there is no confusion with quotes, estimates, or receipts
2. Your business name and ABN: The seller's identity and 11-digit Australian Business Number
3. Date of issue: The date you create and send the invoice
4. Buyer's name or ABN: Required for invoices over $1,000 (recommended for all invoices)
5. Description of items or services: Enough detail for the buyer to identify the transaction
6. Quantity and unit price: For each line item supplied
7. GST amount: Shown per line item or as a total. Alternatively, a clear statement that the total price includes GST
8. Total amount payable: The final amount the buyer owes, including GST

Connecting Invoices to BAS Reporting

Your tax invoices directly feed into your Business Activity Statement. When you lodge your BAS, you report the total GST you have collected from sales (GST on sales) and the total GST you have paid on business purchases (GST on purchases). The difference determines whether you owe the ATO or receive a refund.

Here is how the connection works in practice:

• Label 1A (GST on sales): Add up the GST component from every tax invoice you issued during the BAS period
• Label 1B (GST on purchases): Add up the GST from every valid tax invoice you received from suppliers
• The difference: If 1A is greater than 1B, you owe the ATO. If 1B is greater, you get a refund

Keeping your invoices well-organised throughout the quarter makes BAS time straightforward. If you track expenses and invoices in a tool like BizziKit Financial Accounting Tools, the totals are already calculated for you.

Common GST Invoice Mistakes to Avoid

Even experienced business owners make these errors, and each one can trigger ATO scrutiny or cost you money:

1. Missing or Incorrect ABN

An invoice without your ABN is not a valid tax invoice. Buyers cannot claim input tax credits, and they may be required to withhold a significant portion of the payment. Always double-check the ABN is correct and formatted properly (XX XXX XXX XXX).

2. Not Showing GST Separately

While you can state "total price includes GST," it is far better practice to show the GST amount explicitly. This makes it immediately clear to the buyer, reduces queries, and simplifies BAS calculations for both parties.

3. Charging GST When You Should Not

If you are not registered for GST, you must not charge it or show a GST amount on your invoices. Doing so is misleading and potentially illegal. Conversely, if you are registered, you must charge GST on all taxable supplies.

4. Using the Wrong GST Rate

Australia has a flat 10% GST rate. Unlike countries with multiple rates (such as the UK or EU), there is no reduced rate in Australia. If you are calculating GST from a GST-inclusive price, divide the total by 11 to get the GST component.

5. Forgetting to Issue Invoices Promptly

You must provide a tax invoice within 28 days of a buyer's request. Delays frustrate customers and make your own record-keeping harder at BAS time. Issue invoices as soon as the work is completed or goods are delivered.

Create GST Invoices for Free

You do not need expensive accounting software to issue compliant GST invoices. BizziKit Invoice Builder is a free, browser-based tool that includes Australian GST tax presets, automatic GST calculations, and all the mandatory fields the ATO requires. Your data stays on your device -- nothing is uploaded to the cloud.

Simply select the Australia 10% GST preset, fill in your business details and ABN, add your line items, and export to PDF. The invoice will include the correct GST amounts, your ABN, and the "Tax Invoice" heading automatically. You can also save templates for recurring clients so you never have to start from scratch.

Getting your GST invoicing right from the start saves you time at BAS lodgement, keeps the ATO happy, and ensures your business clients can claim their credits without delay. Start with a compliant template, stay consistent, and make invoicing one less thing to worry about.