When do I need to register for GST as a tradie?

You have to register for GST once your GST turnover reaches $75,000 in a 12-month period, or you expect it to. Below that, registration is optional for most sole traders and tradies. Taxi and ride-sourcing drivers are the exception: they must register from the first dollar. This is the rule as of October 2026.

When do I have to register for GST?

You must register when your GST turnover is $75,000 or more, or when it is likely to be. The ATO checks it two ways:

• Current GST turnover: this month plus the previous 11 months.
• Projected GST turnover: this month plus the next 11 months.

If either figure reaches $75,000, you are required to register. The ATO's guidance says to register within 21 days. Business.gov.au words it as 21 days from when you become aware you will go over. Treat whichever comes first as your deadline.

You need an ABN before you can register. If you don't have one yet, read our guide on how to invoice as a plumber for how ABNs and GST show up on a real invoice, or get your ABN sorted first.

What counts as GST turnover?

GST turnover is your gross business income, not your profit. Count what you invoice before costs come out. The ATO's guidance excludes:

• the GST included in your sales
• sales that aren't connected to your business
• input-taxed sales (financial supplies are the common example)
• sales not connected with Australia

GST-free sales still count towards the total. Always check the ATO's current pages for edge cases like selling equipment or related businesses.

Is it a rolling 12 months or a financial year?

It is a rolling 12 months, not the financial year. You need to check every month. A tradie who has a quiet June and a huge March can cross the line in the middle of the year, so don't wait for 30 June.

Here is a worked example. You invoiced these amounts, all GST-exclusive:

Period	Invoiced
Previous 11 months	$68,000
This month	$8,500
Total (current GST turnover)	$76,500

That is over $75,000, so the 21-day clock is running.

What happens if I register late?

If you were required to register and didn't, you may have to pay GST on sales made since the date you should have registered. The catch is that you probably didn't charge your customers that GST, so it can come out of your own pocket. You can also ask to backdate a registration, which is limited to 4 years.

Should I register for GST before I hit $75,000?

You can register voluntarily at any turnover. Generally you then have to stay registered for at least 12 months.

	Registered	Not registered
Charge 10% GST on invoices	Yes	No
Claim GST credits on tools, fuel and materials	Yes	No
Lodge a BAS	Yes	No
Price vs GST-registered competitors	Matches	Can look cheaper to consumers

If most of your customers are households, not registering keeps your price lower. If you sell to builders and businesses who claim the GST back anyway, and you buy a lot of materials, registering early often costs you nothing and gets you credits.

Do I charge GST to every customer once registered?

Yes, on taxable sales. Once your registration is effective, 10% GST goes on top of your price for normal trade work, whether the customer is a homeowner, a builder or a business. Set your quoted prices with that in mind. If you quote $2,000 before registration and the customer expects to pay $2,000 total, you will cover the $200 GST yourself. Quote "plus GST" or "inc GST" clearly on every quote, so there are no surprises when the invoice arrives.

How do I keep track of my turnover each month?

Add up your invoiced sales for the last 12 months, excluding GST, on the same day each month. A simple spreadsheet works, or use your invoicing app's sales report. Two habits help:

• Check on a fixed date, such as the first of the month, and write the number down.
• Look ahead too. If you've just won a big job, add the expected income over the next 12 months. The projected test can trigger registration before the money arrives.

Keeping every invoice and quote in one place makes this a two-minute job. Our electrician invoicing guide shows how to keep your invoice records tidy from day one.

How do I register for GST?

Register through Online services for business, by phone on 13 28 66, through your tax or BAS agent, or with the Add a new business account (NAT 2954) form. Have your ABN ready. Once registered, you must put GST on your invoices from your effective date.

What changes on my invoices once I register?

Every invoice for a taxable sale must show your ABN, the words "tax invoice", and the GST amount or a note that the total includes GST. A $1,100 job including GST is $1,000 plus $100 GST.

Invogo adds your ABN and the 10% GST to every invoice automatically, and verifies your ABN. The free plan covers 5 invoices or quotes a month, so you can switch it on the day you register. You can also see the trade-specific setups for plumbers, electricians and builders, or start at /signup.

General information, not advice. Check with your accountant or the ATO for your situation.