Tax & GST
What goes on a personal trainer invoice
A short list of things is legally required. A slightly longer list is what gets you paid on time and stops arguments about how many sessions are left. Here are both — and the difference between an invoice and a tax invoice, which is not a wording choice.
Every invoice you send should carry your business name, your ABN, the date, a clear description of what the client is paying for, and the total. That's the floor.
If you're registered for GST, the document is a tax invoice. It has to say so, and it has to show the GST — either as an amount or as a statement such as "Total price includes GST". Once a single invoice hits $1,000 or more, it also has to identify the buyer.
If you're not registered, you send a plain invoice with no GST line and no "tax invoice" heading. Getting either of those wrong is a bigger problem than it looks.
An invoice and a tax invoice are different documents
These get used interchangeably in conversation and they shouldn't be. A tax invoice is a specific document with a specific job: it's what lets a GST-registered buyer claim back the GST they paid you. Only a registered seller makes taxable sales, so only a registered seller issues a tax invoice.
If you're under the $75,000 GST turnover threshold and haven't registered, none of your sessions carry GST. There's no credit for anyone to claim. The document you send is an invoice — a request for payment and a record of what it was for. It's a perfectly complete document. It just isn't a tax invoice, and it shouldn't say it is.
Calling it a tax invoice tells your client there's GST inside the price. If they're registered, their bookkeeper will claim one-eleventh of it as a credit they were never entitled to — an error that started with your paperwork and lands on their BAS.
Worse is adding 10% to your rate, calling that amount GST, and not being registered. You have then collected money as tax that you have no entitlement to keep. If that's happening, stop and talk to your agent this week rather than at the end of the quarter.
What a tax invoice has to show
Once you're registered, this is the list. It's short, and nothing on it is hard — the failures are almost always a missing ABN or a total with no GST statement anywhere near it.
| Element | What that means in practice |
|---|---|
| That it's intended to be a tax invoice | The words Tax invoice at the top. Not "Invoice", not "Statement". |
| Your identity as the seller | Your business or trading name. If you trade under your own name, that's fine. |
| Your ABN | Every time. This is the element most often missing from a PT invoice. |
| The date it was issued | The issue date, which is not necessarily the date of the sessions. |
| A description of what was sold | Enough that a stranger could tell what was bought — and the quantity where quantity applies. "8 × 60-minute personal training sessions" beats "PT". |
| The GST | Either the GST amount shown separately, or a statement such as Total price includes GST. |
| Which parts of the sale carry GST | Only matters if some lines don't. For most trainers everything on the invoice is a taxable sale, so a single "includes GST" statement covers it. |
| The buyer's identity or ABN | Required once the sale is $1,000 or more. A ten-session pack clears that easily. |
The $1,000 line is the one that catches trainers: a pack invoice crosses it, a single-session invoice never does. Put the client's full name — and their ABN where they're a business — on every invoice, and the threshold stops being something you have to think about.
The $82.50 rule, from both sides
If your client is a GST-registered business — a gym paying you, a company buying sessions for staff — they need a valid tax invoice from you to claim a GST credit on anything over $82.50 including GST. In practice, almost everything you invoice a business for sits above the line.
It runs the other way too. To claim a GST credit on your own purchases above $82.50 you need a tax invoice from the supplier — a bank statement line isn't enough, because it shows an amount and a merchant, not what you bought or whether it carried GST. More on GST credits and what doesn't qualify →
What a PT invoice should also carry
None of the following is legally required. All of it is the difference between an invoice that gets paid and an invoice that starts a conversation.
- What the sessions were, and when. Dates, not just a count. "8 × 60-minute sessions, 3 June – 28 June" answers the question before it's asked.
- The remaining pack balance, if this is a prepaid pack. More on this below — it's the most valuable line on the page.
- Payment terms. A real due date. "Due 14 days from issue — 7 August" is a deadline. "Payment on receipt" is a hope.
- How to pay. BSB and account number, or a payment link. Every extra step between reading the invoice and paying it costs you days.
- Your contact details. Email and mobile, so a query comes to you instead of becoming a reason not to pay yet.
The pack balance line
Nearly every dispute a personal trainer will ever have about sessions is the same dispute: the client is certain they have three left, you're certain they have one. Neither of you is lying. One of you didn't write something down in March.
Putting the balance in writing every time money changes hands ends that permanently. A line as plain as "Sessions remaining after this invoice: 4" means the worst disagreement you can ever have is one pack old, with a paper trail already sitting in their inbox. How to track prepaid packs properly →
Numbering, and why sequential matters
Number every invoice, and number them in sequence. INV-0041, INV-0042,
and so on. It looks like bookkeeping pedantry until one of three things happens.
- A payment lands with no reference. With numbers you match it in seconds. Without them you're comparing amounts against a list of clients who all pay $480.
- A client says they already paid that one. Sometimes they have. A number turns that into a two-message exchange rather than a standoff.
- Someone asks you for a period's invoices. An unbroken sequence shows the set is complete. Gaps are a question, and eighteen months later you won't remember the answer.
Never reuse a number, and don't restart at 1 each financial year unless the year is in the number
(26-0041). If you void one, leave the number voided rather than reissuing it.
This is the part nobody keeps up manually
The rules take five minutes to learn. Applying them across forty invoices a quarter — right ABN, right GST statement, right number, and a pack balance that's actually current — is where it falls apart, usually in the second month. Momentum Tracking builds the invoice from the sessions you've already ticked off: your ABN and your sequential invoice number on it, the session breakdown written out, and the client's pack balance kept current in their record.
See how it works → Built by an Australian PT of 12 years. Free 30-day trial.When the gym writes the invoice instead of you
Some gyms don't want invoices from their trainers at all. They run their own pay cycle and issue the tax invoice themselves, on your behalf. That's a recipient created tax invoice, and it's a legitimate arrangement — but only in the circumstances the ATO allows, and only where there's a written agreement between you and the gym covering it.
If money is arriving from a gym and no invoice has ever left your phone, find out which arrangement you're actually in, then get a copy of every RCTI they issue. They're your income records; the fact that someone else typed them doesn't change that.
Keeping copies
Keep them for five years from the date you lodge the return they support. That means copies of what you issued, not just a bank feed of what you were paid — the payment shows an amount, the invoice shows what it was for. The same five years applies to the receipts backing your expenses. The full deductions and records checklist →
If you invoice by opening the same document, changing the name and the number, and saving over the top, you don't have five years of invoices. You have one invoice that has been edited two hundred times. Export a PDF of every invoice as you send it, or use something that stores each one as its own record.
Getting paid
An invoice is a payment instruction, and how you set it up decides how much chasing you do later.
Set terms before the first session
Terms agreed up front are terms. Terms invented after an invoice goes unpaid are an argument. Put them in writing when the client starts — how much, when it's due, what happens to a late cancellation, whether a pack expires. Anything you'd want to rely on later, a late fee included, has to have been agreed at the beginning.
Charge for packs up front
This is the single change that fixes most personal training cash flow. A pack paid before the first session is money in your account and a balance you owe in sessions. A pack invoiced afterwards is a debt, and debts have to be chased.
It also changes the relationship. The client who has paid for ten sessions turns up to the ninth one in the rain — committed money is committed attention. Working out what to charge in the first place →
When someone doesn't pay
Have a sequence and apply it identically to everyone, so it's never a judgement you have to make about a person you like:
- Day after due. A short, factual reminder. Most late invoices are unread, not refused.
- A week later. A phone call. Warmer than email and considerably harder to leave sitting there.
- Then stop delivering on credit. No further sessions until the balance clears.
The mistake is training someone for another three weeks while the number grows, because you don't want the conversation. It was easier at $180 than it will be at $720. A stated rule that applies to everyone is kinder than a judgement call about one person.
Common questions
Can I issue a tax invoice if I'm not registered for GST?
No. A tax invoice is the document a GST-registered seller issues for a taxable sale, and its job is to let a registered buyer claim a GST credit. If you're not registered, your sales don't carry GST, there's no credit for anyone to claim, and what you send is simply an invoice. Heading it tax invoice tells the client there's GST in the price when there isn't.
What has to be on a tax invoice in Australia?
That the document is intended to be a tax invoice, your identity as the seller, your ABN, the date it was issued, a description of what was sold including quantity where that applies, and the GST — shown either as an amount or as a statement such as Total price includes GST. For sales of $1,000 or more it also has to show the buyer's identity or ABN.
Do I need to put my ABN on my invoices?
Yes, in practice. Your ABN is a required element of a tax invoice, and on a plain invoice it's what stops a business client from having to withhold tax from your payment before you see it. Plenty of gyms won't process an invoice without one.
How long do I have to keep copies of my invoices?
Generally five years from the date you lodge the return the record supports. That means copies of the invoices you issued, not only the payments you received. A PDF filed by date is a record. A template you overwrite each time is one invoice, not a set.
Do I have to give a client an invoice at all?
If you're registered for GST, a business client who wants to claim a GST credit needs a tax invoice from you, and where they ask for one you're generally required to provide it within the period the ATO sets. If you're not registered there's no tax invoice to give — you send a plain invoice. For a private client paying for their own training there's no equivalent obligation, but the invoice is your record as much as theirs, so issue one anyway.
What should I do about a client who doesn't pay?
Work the sequence, and apply it to everyone the same way. A short factual reminder the day after the due date, a phone call a week later, and a stop on further sessions until the balance clears. The mistake is letting the balance grow while you keep training them, because the conversation only gets harder as the number gets bigger.