GST registration: the $75,000 threshold and the voluntary registration decision

A business must register for GST within 21 days of its GST turnover reaching $75,000 or more ($150,000 for non-profit organisations) under either the backward-looking or forward-looking rolling 12-month test, and anyone providing taxi, limousine or ride-sourcing travel must register regardless of turnover, before their first trip. Below the threshold, registration is optional: it unlocks GST credits on business purchases, but adds 10% GST to taxable sales and ongoing BAS obligations, and generally requires staying registered for at least 12 months — a trade-off that depends on your circumstances.

Key points:
- The thresholds — **$75,000** for businesses and **$150,000** for non-profit organisations — are verified current at 12 July 2026 on the ATO’s [Registering for GST](https://www.ato.gov.au/businesses-and-organisations/gst-excise-and-indirect-taxes/gst/registering-for-gst) page. No change has been enacted.
- The turnover test rolls monthly in both directions: **current GST turnover** (this month plus the previous 11) or **projected GST turnover** (this month plus the next 11) — it is not a financial-year figure, and unregistered businesses should check each month.
- GST turnover is total business income, *not profit*, with specific exclusions; projected turnover ignores capital-asset sales and wind-down sales, and registration is not required if projected turnover will stay below the threshold even where current turnover is at or above it.
- Taxi, limousine and ride-sourcing providers must register from the first dollar — before the first trip — and must report GST monthly or quarterly.
- Registering late can mean paying GST out of your own margin on taxable sales made since the date registration was required, plus possible penalties and interest; backdating is generally capped at 4 years.
- Voluntary registration below the threshold unlocks GST credits on business purchases (and is required before fuel tax credits can be claimed), but brings 10% GST on taxable sales, BAS lodgement and a general 12-month minimum — who your customers are usually drives the decision.