If you’re running a business in Australia and your revenue is growing, chances are GST registration is sitting somewhere on your to-do list. It’s one of those tasks that feels complicated until you actually sit down and work through it — and then you realise it’s mostly just paperwork and a few clicks through the ATO’s online portal.

This guide walks you through everything: what GST actually is, who needs to register, how to do it, and what happens after. Whether you’re a sole trader just crossing the threshold or a small business that’s been putting this off, here’s what you need to know.

What Is GST in Australia?

GST — Goods and Services Tax — is a 10% tax applied to most goods and services sold in Australia. It was introduced by the Australian Government in 2000 and is administered by the Australian Taxation Office (ATO).

The way it works in practice: your business collects GST from customers on top of the sale price, holds it temporarily, and then passes it on to the ATO when you lodge your Business Activity Statement (BAS). You’re essentially acting as a collection agent for the government.

What makes GST interesting is the credit system. When your business pays GST on purchases — supplies, software, equipment — you can claim those amounts back as input tax credits. So you’re only ever paying GST on the difference between what you collected and what you paid. It’s a reasonably fair system once you get your head around it.

Who Must Register for GST?

Registration becomes mandatory once your business hits certain turnover thresholds. Here’s a quick breakdown:

The $75,000 threshold catches most small businesses eventually. What matters here is GST turnover — roughly, your gross business income from sales connected to Australia, before expenses. It’s not profit, and it’s not net income. Total sales.

Rideshare and taxi drivers get a special mention because the ATO has a firm rule: if you’re carrying passengers for a fare, GST registration is required from day one, regardless of how little you earn. A Brisbane Uber driver doing 10 hours a week still needs to register.

Benefits of Voluntary GST Registration

Businesses below the $75,000 threshold can register voluntarily, and honestly, quite a few find it worth doing.

Here’s why it makes sense for some:

Claim input tax credits. Every time your business pays GST on an expense — a laptop, a software subscription, contractor invoices — you can claim that money back. For a freelance graphic designer spending thousands on Adobe licences and equipment, those credits add up.

Credibility with larger clients. In practice, some government agencies and larger Australian businesses prefer to work with GST-registered suppliers. It signals you’re running a legitimate, growing operation. A small consulting firm pitching for government contracts will often register early for exactly this reason.

Future-proofing. If your revenue is trending toward the threshold, registering early smooths the transition. Scrambling to register after you’ve already crossed $75,000 — and potentially having charged customers without including GST — creates avoidable headaches.

For an e-commerce store pushing $50,000 in annual sales, voluntary registration is worth a conversation with a tax professional.

Requirements Before Registering for GST

Before you can register for GST, a few things need to be in order:

• An active Australian Business Number (ABN). No ABN, no GST registration. If you don’t have one, apply through the Australian Business Register (ABR) first — it’s free and usually processed within a few minutes.
• A confirmed business structure. Sole trader, partnership, company, trust — the structure affects how you register and how GST obligations work.
• Estimated annual turnover figures. The ATO will ask for these during the registration process.
• Business contact and banking details. You’ll need an email address associated with the business and bank account details for any refunds.

If you’re not sure about your structure, sort that out first. Registering under the wrong entity can cause problems down the track.

How to Register for GST Online

The online process through the ATO is the fastest and most straightforward option. Here’s how it works, step by step.

Step 1: Log In to Online Services for Business

Head to the ATO’s Online Services for Business portal and sign in using your myGovID credentials. If you haven’t set up myGovID yet, that’s a five-minute process through the myGovID app using your Australian identity documents.

Step 2: Verify Your Business Information

Once logged in, confirm your ABN and entity details are accurate. The system pre-populates this from the Australian Business Register, but it’s worth checking that everything matches your current situation.

Step 3: Select GST Registration

Navigate to the tax registrations section and add GST. The portal will ask whether registration is mandatory or voluntary — answer honestly based on your turnover.

Step 4: Choose Your Reporting Cycle

You’ll need to nominate how often you’ll lodge your BAS:

• Monthly — higher-turnover businesses or those wanting tighter cash flow control
• Quarterly — the most common choice for small businesses; manageable and not too disruptive
• Annual — available for very small businesses, but comes with a quarterly instalment requirement

For most Australian small businesses, quarterly is the sweet spot. It keeps reporting manageable without letting GST obligations pile up.

Step 5: Submit the Application

Review everything, confirm the details, and submit. Registration is usually processed immediately or within a few business days.

Alternative Ways to Register for GST

Not everyone wants to navigate the ATO portal solo. Totally understandable.

Through a registered tax agent. Hand the whole thing to a professional. They’ll handle the registration and make sure you’re set up correctly from the start. Worth doing if your business situation is complex or you’re unsure about your structure.

By phone with the ATO. Call 13 28 66. The ATO’s business line can process GST registrations over the phone.

During your ABN application. If you’re applying for an ABN for the first time, you can tick the GST registration box at the same time and handle both in one go.

Via a business registration service. The Australian Government’s business.gov.au platform combines several registrations in a single workflow.

What Happens After GST Registration?

Registration isn’t a set-and-forget task. Once you’re registered, a few things change immediately.

You’ll need to add GST to the price of your taxable sales. You also need to issue tax invoices — not just regular invoices — for any sale over $82.50 (including GST). A compliant tax invoice includes your ABN, the words “tax invoice,” the GST amount, and a description of the goods or services.

Record keeping becomes more important. Hold onto receipts and invoices for at least five years — both for claiming input tax credits and for defending your position if the ATO ever reviews your activity.

And you’ll need to lodge your BAS on time, every reporting period. Late lodgements attract penalties.

How to Lodge and Pay GST

Your BAS brings together your GST collected and GST paid during the reporting period. The difference is either what you owe the ATO or what the ATO owes you.

BAS lodgement deadlines (quarterly, as a general guide):

Most accounting software — Xero, MYOB, QuickBooks — can pre-fill BAS data directly from your transactions, which saves a lot of manual work. If your numbers aren’t adding up, that’s a conversation to have with your bookkeeper before lodgement, not after.

Payment can be made via BPAY, direct debit, or through the ATO portal. If cash flow is tight, the ATO does offer payment plans — it’s worth contacting them early rather than missing the deadline.

Common GST Registration Mistakes to Avoid

A few errors that cause real headaches:

Missing the $75,000 threshold. Some business owners don’t realise they’ve crossed the line until months later. Check your turnover regularly, especially if you’re growing quickly. Once you hit the threshold, you have 21 days to register.

Registering under incorrect business details. GST needs to be registered under the correct entity — the ABN holder. Mixing up a personal ABN with a company registration is a surprisingly common mistake.

Charging GST before registration is confirmed. Don’t do this. Charging customers GST before you’re officially registered means you’re collecting a tax you’re not authorised to collect.

Failing to keep receipts. No receipt, no input tax credit claim. Keep everything, even small purchases — they add up across a year.

Missing BAS deadlines. The ATO charges failure-to-lodge penalties. Set calendar reminders or use accounting software with automated reminders.

GST Registration Examples for Australian Businesses

Sydney e-commerce store: An online retailer selling homewares crosses $75,000 in annual revenue. Mandatory registration applies. They add GST to all Australian sales, issue tax invoices, and lodge BAS quarterly.

Melbourne freelance consultant: A strategy consultant earning $60,000 registers voluntarily. The input tax credits on their software, home office expenses, and professional development courses reduce their net GST liability significantly.

Brisbane rideshare driver: Works part-time through a ride-booking platform and earns $30,000 annually. Despite being well below the standard threshold, registration is mandatory from the first fare.

Can You Cancel GST Registration?

Yes. If your business closes, your turnover drops below $75,000 and stays there, or your business structure changes significantly, you can apply to cancel your GST registration.

The process runs through the ATO’s Online Services for Business or via a registered tax agent. The ATO will confirm the cancellation and set an end date. Keep in mind that you still need to lodge a final BAS covering the period up to cancellation.

Cancellation isn’t always the right move just because you dip below the threshold temporarily. If you think turnover will recover, staying registered avoids the disruption of re-registering later.

Frequently Asked Questions About GST Registration in Australia

How much does GST registration cost?

Nothing. Registering for GST through the ATO is completely free.

How long does GST registration take?

Online registration through the ATO portal is usually processed within a few minutes to a few business days. Phone applications take roughly the same timeframe.

Can I register for GST with a new ABN?

Yes. You can register for GST at the same time as applying for your ABN, or any time after. There’s no waiting period once your ABN is active.

Do sole traders need GST registration?

Sole traders follow the same rules as other business structures. If your annual GST turnover hits $75,000 or more, registration is mandatory. Below that, it’s voluntary — but many sole traders register early to claim input tax credits and appear more professional to larger clients.

What happens if I register late?

The ATO can charge penalties for failing to register on time. You may also need to account for GST on sales made after you crossed the threshold — even if you didn’t collect it from customers. In other words, the liability exists whether or not you’ve charged GST. Getting onto registration early prevents this from becoming a problem.

Can I claim GST on past purchases?

Generally, you can claim GST credits on purchases made for your business before registration — but only if you still hold those assets and they’re used in your GST-registered business. The rules here are specific, so it’s worth talking to a registered tax agent to work out what applies to your situation.