BAS & GST Explained: A Small Business Guide

BAS and GST are two of the most common reasons Australian business owners feel the stress creep in every quarter. The good news: once you understand what they actually are and how they fit together, they’re far less intimidating than the acronyms suggest.

Here’s the simple guide – what they are, when they apply to you, and how to stop them being a headache.

Let’s start with GST

GST – Goods and Services Tax – is a 10% tax on most goods and services sold in Australia. If you’re registered, you add 10% to what you charge customers, collect it on the government’s behalf, and pass it on to the ATO. In return, you can claim back the GST you paid on your own business purchases.

That “claim back” part is the bit people miss. GST isn’t purely a cost to your business, you’re essentially a collection point. You gather GST on your sales, offset it against the GST on your expenses, and remit (or get refunded) the difference. The tax is ultimately worn by the end consumer, not you.

Do you have to register for GST?

You must register for GST if:

• Your business has a GST turnover of $75,000 or more (that’s $150,000 for non-profits)
• You provide taxi, ride-share or similar services regardless of turnover
• You want to claim fuel tax credits.

Below the threshold, registration is optional. Some businesses register voluntarily anyway – for instance, if they have big upfront costs and want to claim the GST back, or if they’d rather not flag their size to customers by not charging GST. It’s a judgement call worth talking through, because it’s not always obvious which way is better.

Once you hit the threshold, you’ve got 21 days to register. Miss it, and you can end up liable for GST you never collected – an expensive way to learn the rule.

Now, what is a BAS?

A BAS – Business Activity Statement – is the form you use to report and pay several tax obligations to the ATO in one hit. GST is the main one, but a BAS can also cover:

• PAYG withholding: tax you’ve withheld from employees’ wages.
• PAYG instalments: pre-payments toward your own income tax.
• Other obligations: like fuel tax credits or wine equalisation tax, if they apply.

So the BAS isn’t a tax in itself. It’s the reporting and payment mechanism that bundles your GST and a few other obligations together. When someone says “I’ve got to do my BAS,” they usually mean reconciling the quarter’s GST and lodging the statement.

How often do you lodge?

It depends on your size:

• Quarterly: the most common cycle for small businesses.
• Monthly: generally required for larger businesses (GST turnover of $20 million or more), or optional if you prefer tighter cycles.
• Annually: available to some smaller, voluntarily registered businesses.

For quarterly lodgers, each BAS is generally due 28 days after the quarter ends, so the July–September quarter is due 28 October, and so on. The October–December quarter gets a bit more breathing room, with a due date in late February to account for the holidays.

One genuinely useful perk: if you lodge through a registered BAS or tax agent, you often get extended due dates. It’s one of several reasons handing this to a professional tends to pay for itself.

The mistakes that cost small businesses

BAS and GST trip people up in predictable ways. The usual suspects:

• Claiming GST on things that don’t have it. Not everything includes GST – bank fees, most residential rent, some food items and various government charges are GST-free or input-taxed. Claiming GST that was never there is a common (and auditable) error.
• Getting the tax code wrong on purchases. GST-free, input-taxed, and out-of-scope all get muddled, and the wrong code quietly throws your figures out.
• Missing the deadline. Late lodgement can mean penalties and interest – avoidable, and annoying.
• Poor record-keeping. No valid tax invoice, no claim. If your paperwork isn’t in order, you can lose legitimate credits you were entitled to.
• Leaving it to the last minute. A quarter’s worth of un-reconciled transactions crammed into the night before the deadline is where mistakes breed.

Almost every one of these traces back to the same root cause: books that aren’t kept accurate and current throughout the quarter.

Cash vs accrual: a quick word

You’ll also choose how you account for GST – on a cash basis (you report GST when money actually changes hands) or an accrual basis (you report it when you issue or receive an invoice, regardless of payment). Smaller businesses often use cash accounting because it lines GST up with actual cash flow, but the right choice depends on your situation. It’s worth a deliberate decision rather than a default.

How good bookkeeping makes BAS a non-event

Here’s the thing: BAS is only stressful when your books are behind. When your transactions are recorded correctly and reconciled as you go, preparing a BAS stops being a quarterly scramble and becomes a quick, clean confirmation of numbers that are already right.

That’s the whole case for reporting-led bookkeeping. Keep the file accurate and current, code everything correctly the first time, and the GST is already sorted long before the BAS is due. No shoebox. No late nights. No guessing.

Where My Accounts comes in

We prepare and lodge BAS for our clients as a matter of course – accurately, on time, and increasingly with the benefit of agent-extended deadlines. Every client has a dedicated Australian client manager across their GST and BAS obligations, backed by a delivery team that keeps the underlying books clean quarter-round, so nothing gets crammed in at the deadline.

The result is simple: BAS stops being something you dread and becomes something you barely think about.

If GST and BAS are eating your time or keeping you up at night, here’s why it’s worth outsourcing the lot. Or book a discovery call and we’ll take it off your plate.