BAS, GST & Compliance: What Every Business Needs to Know

If you run a business in Australia, GST and the Business Activity Statement (BAS) are part of life. Getting them right keeps the ATO happy and your cash flow predictable.

When do you need to register for GST?

You must register within 21 days of your GST turnover reaching $75,000 a year ($150,000 for non-profit organisations). Taxi and ride-sourcing drivers must register regardless of turnover. You can register voluntarily below the threshold, which can make sense if you want to claim GST credits on start-up costs.

How GST works

Once registered, you add 10% GST to your taxable sales and can claim credits for the GST included in your business purchases. To claim a GST credit on a purchase that costs more than $82.50 including GST ($75 plus GST), you need a valid tax invoice.

When is BAS due?

Quarterly BAS due dates for 2026–27, per the ATO. The later dates apply when an eligible BAS is lodged electronically through a registered tax or BAS agent:

• Quarter 1 (July–September): 28 October if you lodge yourself, or 25 November through a registered agent
• Quarter 2 (October–December): 28 February, whether you lodge yourself or through an agent
• Quarter 3 (January–March): 28 April if you lodge yourself, or 26 May through a registered agent
• Quarter 4 (April–June): 28 July if you lodge yourself, or 25 August through a registered agent

Monthly BAS is due on the 21st of the following month, whether you lodge yourself or through an agent. Businesses with turnover up to $10 million that report GST monthly and lodge electronically can lodge their December BAS by 21 February.

What else goes on your BAS?

Depending on your business, your BAS may also report PAYG withholding from employees' wages and PAYG instalments towards your own income tax. Super guarantee is paid separately, not through the BAS.

Cash or accruals?

Businesses with turnover under $10 million can usually account for GST on a cash basis, reporting GST when they're paid rather than when they invoice. For many small businesses this is easier on cash flow.

Common mistakes

• Claiming GST credits without a tax invoice
• Claiming GST on items that didn't include GST, such as bank fees or most wages
• Missing lodgement dates, which can lead to penalties

Want BAS off your plate? SydneyTaxAccountant prepares and lodges BAS for businesses across Australia from our Sydney office. Call 1300 661 380 or book a free consultation.

This article is general information only and doesn't take your personal circumstances into account. Due dates are from the ATO and may change; check ato.gov.au for the current year.