BAS Calculator

Calculate your net GST payable (or refund) and total Business Activity Statement payment including PAYG withholding.

Net GST Payable
$0
GST Collected
$0
Less: Input Tax Credits
$0
PAYG Withholding
$0
PAYG Instalment
$0
Total BAS Payment
$0
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How to Complete Your BAS

Your Business Activity Statement (BAS) brings together several tax obligations into a single lodgement. Understanding each component helps you avoid errors and penalties.

GST Section (G-labels)

The GST section requires you to report total sales (G1), export sales (G2), other GST-free sales (G3), and GST on sales (1A). On the purchases side, you report total purchases (G10), capital purchases (G11), and GST on purchases (1B). Net GST = 1A minus 1B.

PAYG Withholding (W-labels)

If you have employees, you must report the total wages paid (W1) and the tax withheld (W2). The withheld amount is paid directly to the ATO as part of your BAS. Failure to remit PAYG withholding incurs significant penalties.

PAYG Instalments (T-labels)

The ATO may require self-employed individuals and investors to pay PAYG instalments toward their own income tax. The instalment amount (T7) is set by the ATO based on your prior year income. You can vary it if your income has changed significantly.

Lodgement and Payment

Most small businesses lodge quarterly. Your BAS can be lodged online through myGov, your accounting software, or via a registered tax agent. Payments can be made via BPAY, EFT, or the ATO's online payment portal.

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Frequently Asked Questions

What is a BAS?
A Business Activity Statement (BAS) is a form submitted to the ATO to report and pay GST, PAYG withholding, PAYG instalments, and other tax obligations. Most businesses lodge quarterly.
How do I calculate net GST on my BAS?
Net GST = GST collected on sales minus GST paid on purchases (input tax credits). If the result is positive you owe the ATO; if negative, you receive a refund.
What is PAYG withholding on a BAS?
PAYG withholding (W1/W2) is the tax you withheld from employee wages and must remit to the ATO. It is separate from GST and added to your total BAS payment.
What is a PAYG instalment?
PAYG instalments (T-section of BAS) are prepayments of your own income tax if you are self-employed or have investment income. The ATO sets the instalment amount based on prior year income.
When is my BAS due?
Quarterly BAS due dates: Q1 (Jul–Sep) due 28 Oct; Q2 (Oct–Dec) due 28 Feb; Q3 (Jan–Mar) due 28 Apr; Q4 (Apr–Jun) due 28 Jul. Registered tax agents get extended deadlines.
Disclaimer: This calculator provides estimates based on the figures you enter. It does not constitute tax advice. Your actual BAS obligations may vary. Always verify with the ATO or a registered BAS agent before lodging.
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