If you run a business as a sole trader and you're registered for GST, you'll need to lodge a Business Activity Statement, or BAS. For a lot of people it's the most confusing part of working for themselves, so this guide covers what a BAS is, whether you actually need to lodge one, when it's due, and the practical steps to get it done.
What is a BAS?
A Business Activity Statement (BAS) is a form you lodge with the Australian Taxation Office (ATO) to report and pay certain business taxes. For most sole traders, the main thing a BAS reports is GST: the goods and services tax you've collected on your sales, less the GST you've paid on your business purchases.
Depending on your circumstances, a BAS can also cover things like PAYG instalments (pre-payments towards your income tax) and PAYG withholding (if you have employees). Most sole traders without staff are mainly dealing with the GST side.
Do sole traders need to lodge a BAS?
Not every sole trader has to lodge a BAS. The key question is whether you're registered for GST:
- Registered for GST - you lodge a BAS (usually quarterly) to report your GST.
- Not registered for GST - you generally don't lodge a BAS at all. You still lodge your annual income tax return.
You must register for GST once your business turnover reaches $75,000 or more in a 12-month period (there are some special cases, such as taxi and rideshare drivers, who must register regardless of turnover). Below that threshold, registering is optional. If you're unsure where you sit, the ATO's GST registration guidance is the place to check.
BAS due dates for sole traders
Most sole traders report GST quarterly. The standard quarterly due dates are:
| Quarter | Period | Standard due date |
|---|---|---|
| Q1 | July – September | 28 October |
| Q2 | October – December | 28 February |
| Q3 | January – March | 28 April |
| Q4 | April – June | 28 July |
If you lodge online or through a registered tax or BAS agent, you may get extra time beyond these dates. Some businesses report GST monthly or annually instead of quarterly, which changes the dates. Always confirm against the ATO's BAS due dates for your situation.
What you need before you lodge
Lodging is much faster if your records are already in order. Before you start, have these on hand:
- Your total sales for the period, and the GST included in them.
- Your business expenses and the GST you paid on them (keep the tax invoices).
- Your bank statements for the period, to check nothing has been missed.
- Any prior BAS, if you want to compare or carry figures forward.
The figure that matters most is the difference between the GST you collected and the GST you paid. If you collected more than you paid, you pay the difference to the ATO. If you paid more than you collected, you may be due a refund.
How to lodge your BAS, step by step
There are three common ways to lodge. Pick whichever suits how hands-on you want to be.
Option 1: Online via myGov / ATO online services
This is the most common option for sole traders who do their own books. Link your myGov account to the ATO, open ATO online services, go to your activity statement, enter your GST (and any PAYG) figures, then review and submit. You'll get confirmation and a payment reference if you owe anything.
Option 2: Through a registered tax or BAS agent
If you'd rather hand it off, a registered BAS or tax agent can prepare and lodge on your behalf. Agents also generally receive later due dates, which can buy you some breathing room. Just make sure they're registered with the Tax Practitioners Board.
Option 3: By mail
If the ATO sends you a paper activity statement, you can fill it in and post it back before the due date. It's the slowest option and the easiest to misplace, but it's still available.
Using accounting software to prepare your figures
Whichever way you lodge, the hard part is usually getting the numbers right. Accounting software tallies the GST on your invoices and expenses as you go, so by the time the BAS is due your figures are already worked out. You're just transcribing them, not reconstructing a whole quarter from a shoebox of receipts. That's exactly what FairBooks is built to do for Australian sole traders.
How to lodge a nil BAS
Had no activity this quarter? You still need to lodge. A nil BAS simply reports zeros, and you can lodge it online in a couple of minutes (or over the phone with the ATO in some cases). Skip it altogether, even with nothing to report, and you can cop a late-lodgement penalty, so it's worth the few minutes.
Common BAS mistakes sole traders make
- Lodging late - or forgetting the nil BAS. Put the due dates in your calendar.
- Mixing personal and business spending - claim GST only on genuine business purchases.
- Claiming GST on GST-free items - not everything has GST on it (some food, for example).
- Leaving it all to the last day - reconciling a whole quarter at once is where errors creep in.
BAS vs your income tax return: what's the difference?
They're easy to confuse, but they're separate. Your BAS is lodged during the year (usually quarterly) and mainly reports GST. Your income tax return is lodged once a year, after 30 June, and reports your income and works out your income tax. Lodging one doesn't replace lodging the other.
Making BAS easier next quarter
The single best thing you can do is keep your books current rather than catching up the night before. When your invoices and expenses are recorded as they happen, your GST total is always ready, and lodging becomes a five-minute job instead of a stressful weekend.
This article is general information only and is not tax advice. Tax rules and dates can change. For guidance on your own situation, check the ATO or speak to a registered tax or BAS agent.