BAS GST Estimate Australia
BAS GST Estimate Australia
This simple calculator estimates the difference between the GST you collected on sales and the GST credits on your business purchases. It is a planning aid and is not a BAS lodgment tool.
How the estimate works
For planning purposes, net GST is the GST collected on your sales minus your eligible GST credits. A positive result means GST payable in this simplified model. A negative result points to a potential refund position, before other BAS items and adjustments are taken into account.
Worked example: an Adelaide bookshop’s quarter
An Adelaide bookshop has a busy quarter. Its taxable sales including GST total $121,000, so the GST collected is $121,000 divided by 11, which is $11,000. Its eligible business purchases including GST total $66,000, so the GST credits are $66,000 divided by 11, which is $6,000. Net GST is $11,000 minus $6,000, which is $5,000 payable. Try it in the estimator above: enter 11000 and 6000, and it shows an estimated net GST of A$5,000.00. If the bookshop had also bought $11,000 of GST-free stock, those purchases would add no credits and the estimate would stay the same.
Simpler BAS
Eligible small businesses can use the ATO’s Simpler BAS method, which cuts down the number of GST labels they need to report. This calculator does not reproduce the BAS form and should not be used as a substitute for proper accounting records. Run the full figures through the BAS GST calculator when you are ready to lodge.
Practical tips for a useful estimate
Base your estimate on real figures from your accounting software, not guesses. Work out the GST component of each total first; the GST component calculator does the divide-by-11 step for you. Remember that adjustments, private-use apportionment and other BAS amounts sit outside this simple model. Run the estimate mid-quarter rather than the night before the BAS is due, and set the expected amount aside in a separate account so the payment does not sting.
Important limitations
- Use actual transaction records for BAS preparation.
- GST-free and input-taxed transactions need correct classification.
- Adjustments and other activity statement amounts are not included here.
- GST credits depend on eligibility and documentation.
Frequently asked questions
Is this estimate the same as my BAS?
No. This is a simplified planning figure. Your actual BAS includes other labels, adjustments and reporting requirements.
What does a negative result mean?
It suggests a refund position, where your GST credits exceed the GST you collected. Other BAS items can still change the final figure.
Do I include GST-free sales in the estimate?
GST-free sales are reported separately on the BAS and sit outside this simple calculation. Include only the GST on taxable sales and eligible purchases here.
When should I run the estimate?
Mid-quarter is ideal. An early estimate gives you time to set money aside or chase missing invoices before the due date.
