Registering for GST in Australia: when you need to and how it works
GST registration: mandatory or voluntary?
Not every business has to register for GST. The ATO sets a turnover threshold — if your actual or expected turnover reaches or exceeds that threshold, registering for GST is mandatory. If you are below the threshold, registering is voluntary.
The specific turnover threshold is set and published by the ATO — check it at ato.gov.au/business/gst/registering-for-gst, because this is information you should confirm with the official source rather than relying on outdated figures.
When should you register even if it is not mandatory?
Some businesses choose to register for GST even when they are below the threshold:
Claiming back GST on inputs: When you are registered for GST, you can claim back (as an input tax credit) the GST you have paid on goods and services bought for the business. If you have large GST inputs (equipment, raw materials), registering can be worthwhile even with low turnover.
Professional image: Some customers, especially other businesses, prefer to deal with a supplier that is registered for GST because they too need a GST invoice to claim back.
Preparing for growth: If you expect to reach the threshold soon, registering early avoids having to switch over midway.
Conversely, if you mainly sell to end consumers (B2C, not B2B) and are below the threshold, not registering helps you avoid extra compliance, and your prices do not need GST added on top.
The GST registration process
GST registration is done through the ATO — you can do it yourself through myGov or Online services for business, or have an accountant or tax agent do it for you.
What you need to register:
- The business’s ABN (you must have an ABN before registering for GST)
- Business details: industry, estimated turnover, and how you will lodge your BAS (monthly, quarterly or annually)
After you register, the ATO confirms and sets up your BAS cycle. Registration takes effect from the date you specify — usually the registration date or the start of the accounting period.
After registering: the practical obligations
Registering for GST is a compliance commitment, not just a privilege:
Collecting GST from customers: You must add GST to the price when you sell GST-taxable goods or services. GST is not your revenue — you collect it on the ATO’s behalf.
Issuing a tax invoice: A customer who wants to claim back GST needs a tax invoice from you. A tax invoice must include: your name and ABN, the date, a description of the goods or services, and the price and GST shown separately (or “GST included” with the total).
Lodging a BAS (Business Activity Statement): On the cycle the ATO sets, you lodge a BAS reporting the GST you collected and the GST you paid. The difference is what you pay the ATO (or what is refunded to you, if the GST you paid is more than what you collected).
Keeping records: Keep all invoices and receipts — both GST collected and GST paid — to support your BAS.
Cancelling GST registration when needed
If your turnover falls below the mandatory threshold, you can cancel your GST registration — but you must be sure your turnover will genuinely stay below the threshold before you cancel. Cancelling and then exceeding the threshold again means you have to re-register and can create a backdated GST debt.
Important note: not every sale has GST
Some goods and services are GST-free — you do not charge GST on these but you can still claim the related GST on inputs. Common examples: fresh food, some health services, education, and goods exported overseas.
If your business has a mix of taxable and GST-free sales, you need to classify them correctly for the BAS to be accurate — an accountant, or ato.gov.au/business/gst, has the full list.