Starting a business in Australia
An ABN in minutes for free, GST at $75,000, and a company only when the ASIC annual fee buys something you need.
Checked against the sources on 2026-08-30
Before anything else
Australia’s sole-trader start is the ABN - the Australian Business Number, applied for free at the Australian Business Register in minutes. With it you invoice; without it, clients must withhold tax at the top rate from your payments, which is the system’s way of making registration universal.
Business income lands in your personal return; there is no separate registration for that. The decisions worth making early are GST (compulsory at $75,000 of annual turnover), a registered business name if trading under one ($45-ish a year via ASIC), and whether the Pty Ltd’s asset protection and 25% small-company rate justify its costs.
The legal shell
Sole trader or Pty Ltd?
Sole trader
The default start.
$0 for the ABN; ~$45/year for a business name if used.
Personal liability, and personal marginal rates to 45%.
Pty Ltd
Liability, contracts, retained profits.
~$600 ASIC registration plus ~$320/year review fee.
The company pays 25% (base rate entities), but personal services income rules can attribute one-client contracting income straight back to you - the structure does not launder PSI.
The sequence
Apply for the ABN
Where: abr.gov.auCost: $0Takes: Usually instant
Free at the official register - the paid lookalike sites are the local trap. myGovID (now myID) is the credential.
Register GST when the line approaches
Where: Through the ATO via myGov or a BAS agent
Compulsory at $75,000 of rolling annual turnover ($150,000 for non-profits; immediately for ride-share). Once in, the Business Activity Statement cycle runs quarterly - GST collected, credits claimed, PAYG instalments alongside.
Plan for tax and super yourself
No employer withholds for you: the ATO moves you onto PAYG instalments after the first bill. Superannuation is voluntary for sole traders - contributing anyway is deductible and is the retirement plan employment used to provide.
What it costs to start
| What | Amount |
|---|---|
| ABN | $0 |
| Business name | ~$45/year |
| Pty Ltd | ~$600 + ~$320/year |
| GST | 10% collected above $75,000 turnover |
The words on the forms
- ABN
- The business number that makes invoicing possible.
- ABR
- The register that issues it, free.
- GST / BAS
- The 10% tax and the activity statement cycle it brings.
- PAYG instalments
- The prepaid income tax rhythm after year one.
- ASIC
- The company regulator collecting the annual review fee.
- PSI
- Personal services income - the rules that see through one-client companies.
- Super
- Superannuation - voluntary and deductible for sole traders.
The traps
- Paying an ABN mill for a free registration.
- Crossing $75,000 mid-year without registering - the GST owed does not wait for you.
- A Pty Ltd built to split one-client income the PSI rules attribute back.
- No super contributions for years because nothing forced them.
Where to check this yourself
- ABRThe free ABN.
- ATOGST, BAS, PSI, PAYG.
- business.gov.auThe whole-of-government guide.
This is a map, not legal or tax advice - and an honest one about how it was drawn: the Germany guide was written by a person who walked the route; most other countries were drafted with AI against the official sources and have not yet been walked by someone who did it. Laws change. Every guide carries the date it was last checked and the sources to check it yourself - and if you have been through one of these routes, your corrections are exactly what this handbook wants.