Australia BAS GST Calculator | GST Collected & Credits
This Australia BAS GST calculator provides an arithmetic estimate of GST on taxable sales and GST included in business purchases. It helps you sanity-check the basic numbers before you dig into the BAS rules.
Australia GST / BAS Calculator
How this calculator works
Enter GST-exclusive taxable sales and GST-exclusive business purchases. The tool applies the standard 10% GST rate, then subtracts the purchase GST from the sales GST.
Worked example: a Townsville cafe’s quarter
A Townsville cafe records $44,000 of GST-exclusive taxable sales in a quarter and $16,500 of GST-exclusive business purchases. GST on sales is $4,400. GST on the purchases is $1,650. The estimate is $2,750 of net GST payable. Enter 44000 and 16500 in the calculator above and it shows the same three figures. For a simpler two-input version of this estimate, try the BAS GST estimator.
Why this is only an estimate
A real BAS can involve GST-free and input-taxed supplies, adjustments, private-use apportionment, tax invoices, accounting methods and other reporting rules. The calculator does not determine whether a purchase creates a GST credit or how a particular BAS label should be completed.
Practical tips: from estimate to lodgment
Run the estimate halfway through the quarter so you can set the likely payment aside. Reconcile the calculator’s figures against your accounting software before lodging, because the software knows about adjustments the calculator ignores. Check your lodgment deadline on the BAS due date guide and lodge online for the extra two weeks. Keep every tax invoice, because the estimate means nothing without the paperwork to back it.
Related tools
Australia GST Calculator · Australia GST Registration Checker · Sources & Methodology
Official source
Frequently asked questions
Can this tool prepare a BAS?
No. It gives you a basic arithmetic estimate to plan with.
Are all business purchases eligible for GST credits?
No. Whether a purchase creates a GST credit depends on the purchase and the ATO rules.
Should I enter GST-inclusive or GST-exclusive figures?
GST-exclusive. The calculator adds the 10% itself. If your figures include GST, strip the GST out first with the divide-by-11 rule.
When is my BAS due?
Quarterly BAS dates are generally 28 October, 28 February, 28 April and 28 July, with extra time for online lodgment. Confirm each date before you lodge.
