Do I need to register for GST as a tradie?

Do I need to register for GST? Yes, once your GST turnover reaches $75,000 in any rolling 12-month period. You then have 21 days to register from the moment you know you will cross the line. Under $75,000 it is optional. Turnover means the total you invoice, not what you keep after costs.

Most tradies hit this question the year the work picks up, and they are worried about two things: getting done by the ATO, and pricing themselves 10% above the bloke down the road for no reason. Both worries are fair. Here is how the rule actually works.

The short answer: the $75,000 threshold

You must register for GST once your GST turnover reaches $75,000 in any rolling 12-month period, and it arrives faster than most tradies expect. Note the word rolling. This is not a financial-year test you check each July. It is any 12 months, so the number can creep over the line in March while you are waiting for the new year to look at it.

A solo chippie billing around $1,500 a week in labour and materials is already at $78,000 a year. Past the line. Plenty of tradies get there in their first proper year without noticing, because they are watching the bank balance, not the invoice total.

The rule comes from the ATO's registering for GST page. Watch the rolling total, and once it reaches $75,000, or you can see that it will, registration stops being optional.

The 21-day rule (don't get caught out)

You have 21 days to register from the moment you become aware your turnover will pass $75,000, not from when it actually does. The clock starts at "I can see it coming", which is earlier than most people assume.

Here is why that matters. If you were required to register and did not, the ATO can hold you liable for GST on the sales you made from that point. You never charged your customers the extra 10%, but you owe it anyway. One eleventh of every invoice, out of your own pocket, on jobs you priced without it.

The fix costs nothing. Once a month, add up your last 12 months of invoices. It takes five minutes. The moment the total is clearly heading over $75,000, register. business.gov.au covers the same rule if you want a second source.

What "turnover" actually means (it's not profit)

Turnover is the gross amount you invoice, not what you keep after costs, and confusing the two is the most common GST mistake there is. The trap sounds like this: "I invoiced $90,000, but $35,000 of that was materials and fuel, so I'm really on $55,000. Under the line."

Wrong, and expensively wrong. The ATO measures the $90,000. Materials you buy and on-charge count. The trailer hire you passed through to the client counts. Think of it as the difference between the total at the bottom of your invoice and what is in your back pocket once the timber and the diesel are paid for. The ATO cares about the invoice total.

So if your gross invoicing is anywhere near $75,000, you are in the zone, and it is time to track the rolling number properly rather than guessing from your take-home.

When registering voluntarily actually helps

Under $75,000 you can register by choice, and for some tradies it genuinely pays off. Registration lets you claim back the GST on business purchases. If you are setting up and about to spend real money on a ute, a trailer and a kit of tools, those credits add up quickly. You need a valid tax invoice for purchases over $82.50 including GST, and the ATO gives you four years to claim, so keep every receipt.

The flip side is real. Registering means charging 10% on top of your prices and lodging a BAS every quarter. If most of your work is for homeowners paying out of their own pocket, that 10% makes you dearer for no visible benefit to them. If most of your customers are builders and other businesses, they claim the GST back anyway, so the bump costs them nothing and registering is close to free.

Who pays you is the deciding lens:

• Turnover at $75,000, or clearly heading there within a few months? Register now.
• Taxi or rideshare work? Register regardless of turnover.
• Under $75,000 but buying a lot of GST-inclusive gear this year? Voluntary registration may pay for itself.
• Under $75,000, mostly homeowner work, no big purchases coming? Leave it for now.
• Not sure where you sit? Add up the last 12 months of invoices, gross.

What changes once you're registered

Three things change on day one: your prices, your paperwork and your reporting. First, you charge 10% GST on top of your prices. Second, your invoices become tax invoices, which must show the GST separately so business customers can claim it back. We cover the exact required fields in what to put on an invoice in Australia. Third, you lodge a business activity statement, quarterly for almost every small operator, reporting the GST you collected minus the credits you claim.

None of it is hard, but it has to be right on every job. In Chippie, once you set your GST status, every quote and invoice marks the GST automatically, so your tax invoices show the GST line the way the ATO requires without you hand-adding 10% each time. It does not lodge your BAS or talk to the ATO; that side is still yours or your bookkeeper's.

How to register (it takes about 10 minutes)

Registering is a short admin job, not a saga. You need an ABN first; if you are still sorting that, start with our first ABN checklist. With the ABN in hand, you register through ATO Online services for business, over the phone on 13 28 66, or through your tax or BAS agent. It is free.

You choose a reporting cycle as part of the process, and most small operators go quarterly. One detail worth knowing: you charge GST from your registration date forward, not on work you did before it, so the date you pick matters if you are mid-job.

FAQ

What is the GST threshold for a sole trader in Australia?

$75,000 of GST turnover in any rolling 12-month period. Turnover is your gross business income, the total you invoice, not your profit. The threshold is the same for sole traders and companies. Non-profits get $150,000, and taxi or rideshare drivers must register from the first dollar.

Is GST based on profit or total income?

Total income. GST turnover is the gross amount you invoice, including materials you on-charge, before any costs come out. A tradie who invoices $90,000 and keeps $55,000 after expenses is over the $75,000 threshold, because the ATO measures the $90,000.

What happens if I don't register for GST when I should?

You can end up owing GST on the sales you made after you should have registered, even though you never charged your customers the 10%. That money comes out of your own pocket. Register within 21 days of knowing your turnover will cross $75,000 and the problem never exists.

Should I register for GST voluntarily if I'm under $75k?

It depends who pays you. If you sell mostly to builders and other businesses, they claim the GST back, so your prices stay competitive and you get credits on your gear. If your work is mostly for homeowners, the 10% price rise usually costs you more than the credits return.

How often do I have to lodge a BAS once registered?

Quarterly for most tradies. Quarterly reporting is available to anyone with GST turnover under $20 million, which covers every small trade business. You lodge online through the ATO or through a registered agent, and agents often get extra time on due dates.

This is general information, not tax advice. Your situation may have wrinkles, so check the ATO pages linked above or ask a registered BAS agent.

If you want the quoting and invoicing side sorted while you deal with the tax side, Chippie's free tier covers 20 jobs a month at chippieapp.com. Easy to skip, there if it helps.