What goes on a GST invoice
A GST invoice — formally called a tax invoice in Australia — must include specific fields to let your client claim a GST credit. Here is what each field is and where it goes.
Header section
“Tax Invoice” — This exact phrase must appear on the document. Place it prominently at the top.
Your business name — Your registered business name or trading name, matching your ABN registration.
Your ABN — Your 11-digit Australian Business Number. Format it in the standard way: XX XXX XXX XXX. This is mandatory on all tax invoices.
Invoice number — A unique reference number for this invoice. Sequential numbering (INV-001, INV-002) is the most common approach and helps both you and your client track documents.
Invoice date — The date you are issuing the invoice. This determines the GST reporting period the sale falls into.
Due date — When payment is expected. Standard terms in Australia are 7, 14 or 30 days from invoice date.
Client section
Client name — The name of the person or business you are invoicing.
Client ABN (for sales over $1,000) — For higher-value invoices, the ATO requires the buyer’s identity. Including their ABN is the clearest way to satisfy this.
Client address — Business or billing address. Useful for the client’s own records and for following up by post if needed.
Line items
Each line item should describe what was supplied and the amount charged. For most invoices, one or two line items is enough. For trade invoices, you may have several — one for labour, one for materials, one for a call-out fee.
Keep descriptions clear and specific: “Website design — homepage and 4 internal pages” is better than “Design work.”
Totals section
Subtotal — The total before GST. This is the sum of all your line items.
GST — 10% of the subtotal. See below for how to calculate this correctly.
Total — The amount the client pays. This is the subtotal plus the GST.
How to calculate GST
GST in Australia is 10%. There are two ways to work with it:
Adding GST to a GST-exclusive price
If your prices do not include GST:
- Subtotal: $500.00
- GST (10%): $50.00 (calculated as 500 × 0.10)
- Total: $550.00
Working backwards from a GST-inclusive price
If you have quoted a GST-inclusive price and need to show the GST component:
- Total (GST-inclusive): $550.00
- GST: $50.00 (calculated as 550 ÷ 11)
- Subtotal (ex-GST): $500.00
The ÷ 11 rule is the standard way to extract GST from a GST-inclusive amount.
Example GST invoice layout
Below is a typical layout for a tax invoice from a service business. All figures are examples only.
TAX INVOICE
Ridge Consulting Group ABN 38 215 749 063 (example)
To: Harrington Property Holdings ABN: 72 540 183 290 (example)
Invoice: INV-0114 Date: 30 July 2026 Due: 13 August 2026
| Description | Amount |
|---|---|
| Property market analysis report | $1,200.00 |
| Strategic planning session — 2 hrs @ $350/hr | $700.00 |
| Subtotal | $1,900.00 |
| GST (10%) | $190.00 |
| Total | $2,090.00 |
Payment: EFT to BSB 062 000 / Account 1234 5678
Common mistakes to avoid
Missing “Tax Invoice” wording — The phrase must appear on the document. “Invoice” alone is not enough for a tax invoice.
No ABN — Your ABN is mandatory. Clients cannot claim GST credits without it.
Incorrect GST calculation — Double-check your arithmetic. $100 + 10% = $110, not $101.
GST on GST-free items — Do not add GST to supplies that are GST-free (fresh food, health services, etc.).
Rounding errors on multiple lines — GST should be calculated on the total, not rounded per line and then summed. Calculate the subtotal first, then apply 10%.
Sending GST invoices with InvoiceSent
InvoiceSent creates GST invoices automatically. You configure your ABN and GST rate once, and they appear on every invoice you send. Line items are totalled, GST is calculated, and the subtotal/GST/total breakdown is displayed in the correct format.
You can send invoices by email or share a secure link — no PDF export or template management required.
Last reviewed: July 2026