How to invoice as a sole trader in Australia (with GST)

What makes a sole trader different from a company, invoice-wise

Trading as a sole trader in Australia is deliberately simple: there's no separate legal entity, no company registration with ASIC, and no annual company return. You trade under your own name (or a registered business name) using your own tax file number, plus one extra thing almost every other structure also needs — an ABN.

Two things flow from this:

You invoice under your own legal name or registered business name, not a company name with an ACN, unless you've actually set up a company.
Business income is your personal income at tax time, so accurate, sequential invoices matter for your own tax return as much as for the client's records.

None of this changes the basic shape of an invoice. It mostly changes what you put in the "who's billing" section at the top.

Get an ABN before you send your first invoice

An Australian Business Number is the one thing you genuinely can't skip. Without it, a business paying you is required to withhold tax from the payment at the top marginal rate — as a rule of thumb, that's roughly 47%, withheld on anything over $75 (excluding GST), unless an exemption applies. Clients who know this will ask for your ABN before they'll pay you at all.

Getting one is free and usually takes minutes online through the Australian Business Register. Put it on every invoice, ideally right under your name, so there's no back-and-forth before payment.

Do you need to register for GST?

This depends on your turnover, and the exact threshold can shift over time, so treat this as a starting point rather than the final word — check the current figure with your accountant or on the ATO website. As a rule of thumb, once your turnover looks like it will reach or pass roughly $75,000 in a 12-month period, you're required to register for GST. Below that, registration is optional; some sole traders register early anyway so they can claim GST credits on tools, stock or a work vehicle.

If you're not registered, don't add GST to your invoices, and don't call the document a "tax invoice" — a plain invoice is correct, and it's fine to simply tell a client you're not GST registered if they ask.

What has to be on a sole trader invoice in Australia

Whether or not you're GST registered, a solid invoice needs:

The word "Invoice" (or "Tax Invoice" if you're GST registered) clearly at the top.
A unique, sequential invoice number — INV-0001, INV-0002, and so on, never reused.
Your name or registered business name, and your ABN.
The date the invoice was issued.
A clear description of the goods or services, with quantity where relevant.
The price, and if you're GST registered, the GST amount shown separately or a note that the total includes GST.
Payment details — your bank account (BSB and account number), and a reference like "please use INV-0042."

A real due date ("Due 3 October 2026") gets you paid faster than a vague "payment terms: 14 days," even though it isn't strictly required.

The $1,000 rule for GST-registered sole traders

If you're GST registered, the ATO has two tiers of detail, and knowing which applies saves you either adding information you don't need or leaving out something a corporate client's accounts team will bounce back to you.

Under $1,000 (GST-inclusive): a simplified tax invoice is enough. It needs the words "Tax Invoice," your identity and ABN, the date, a description of what was supplied, and the GST-inclusive total.

$1,000 or more (GST-inclusive): the ATO also expects the buyer's identity or ABN, and the GST amount shown separately from the price — or a clear statement that the total price includes GST.

In practice, most invoicing software (ours included) just always shows the full breakdown, since it's clearer for everyone and there's no downside to including more detail than the bare minimum requires.

Invoice numbering that keeps your accountant happy

Pick a numbering format — INV-0001 is the easiest — and stick with it for the life of the business: sequential, no gaps, nothing reused. If a client disputes an invoice or you need to cancel one, issue a credit note against it rather than deleting the original. A clean, gapless sequence is one less thing your accountant has to untangle at tax time, and it looks far better if the ATO ever asks questions.

Getting paid faster as an Australian sole trader

The invoice itself does most of the work if a few details are right:

Send it the day you finish the job, not on a set "invoicing day" once a week — the sooner it lands, the sooner it gets attention.
Put a real due date on it. People react to a calendar date far more reliably than to "payment due within 14 days."
Offer an easy way to pay online. Bank transfer using your BSB and account number is standard in Australia, but adding a one-tap Pay now option (card, Apple Pay, Google Pay) removes the most common excuse for delay — as a rule of thumb, invoices with online payment tend to get settled noticeably sooner than bank-transfer-only ones.
Automate the follow-up. A friendly reminder on the due date, and a firmer one a week later, saves you from sending awkward "just checking in" messages yourself.
Ask for a deposit on bigger jobs. For substantial work, 30–50% upfront is common practice among Australian tradies and creatives, and it protects your cash flow if a job stalls partway through.

If a client disputes an amount, sort it out in writing before the due date rather than letting the whole invoice sit unpaid — a quick adjustment or credit note keeps both the relationship and your cash flow intact.

BAS and record keeping

If you're GST registered, you'll report GST through your Business Activity Statement, usually quarterly. Keeping invoices numbered and stored properly throughout the quarter makes filling in a BAS a much shorter job than reconstructing it from a folder of PDFs the week it's due — worth setting up early rather than fixing later. The ATO generally expects business records, including invoices issued and received, to be kept for five years; check the current requirement and how it applies to your situation with your accountant, since record-keeping obligations can vary depending on your structure and circumstances.

Template, spreadsheet, or a proper tool?

A Word or Excel template is a completely reasonable way to send your first few invoices — free, and quick to set up. Where it starts costing you time is numbering (easy to duplicate without noticing), tracking who's actually paid, and remembering to chase the ones who haven't. Once you're sending more than a handful a month, that admin adds up fast.

That's the gap InvoiceCharlie is built to close: correct ABN and GST-ready invoice formatting, sequential numbering handled automatically, a Pay now button, and reminders that go out without you lifting a finger. You can create a proper GST-ready invoice for free right now with no account needed, and when you're ready for numbering, reminders and online payment sorted for you, your first 10 invoices are free.