Guides · Tax and BAS · 5 min read · Updated 25 September 2026
GST for tradies: when to register, what to charge, what to claim
GST is the ten percent on nearly everything you sell and nearly everything you buy for the business. Once you understand that it is money you collect for the ATO, not income, the rest is arithmetic.
When you must register
When your GST turnover reaches $75,000 in any rolling 12 months, or when you expect it to. You have 21 days to register once you cross it. Below that, registration is optional; many tradies register anyway to claim credits on tools and materials, and because commercial customers expect a tax invoice.
Charging it
- Add ten percent to your ex-GST price. $1,000 of work is $1,100 on the invoice.
- Quote the GST-inclusive price to domestic customers; they think in totals. Show the GST amount on the document.
- The words Tax invoice, your ABN and the GST amount are required on the invoice.
- If you are not registered, do not charge GST and do not call the document a tax invoice.
Claiming it back
- You can claim the GST in business purchases: materials, tools, fuel, phone, insurance, software, the ute.
- You need a tax invoice for anything over $82.50 including GST.
- Private use reduces the claim: a phone used 80 percent for work gives an 80 percent credit.
- Some things carry no GST, such as bank fees and wages. No GST means no credit.
Where it lands
On the BAS. GST collected on sales goes to label 1A, GST paid on purchases to 1B, and you pay or receive the difference each quarter. Keep one-eleventh of every customer payment in a separate account and the quarter's GST is already there. SmokoBooks shows the running GST position on the dashboard so it is never a surprise.
Common questions
I am under $75,000. Should I register anyway?+
If you buy a lot of materials or tools, the credits are worth it. If your customers are mostly homeowners and your costs are low, staying unregistered keeps your prices ten percent lower. Ask your accountant, and remember you must register once you cross the threshold.
Is GST charged on labour?+
Yes. GST applies to the whole supply, labour and materials, when you are registered.
What about cash jobs?+
Income is income, and GST applies, regardless of how the customer pays. Unreported cash income is the most common reason tradies end up in an audit.
General information for Australian sole traders and small trade businesses, not tax or legal advice. Thresholds, rates and due dates change: confirm the current figures on ato.gov.au or with your accountant.