Free · Quarterly BAS · AU

Prepare your BAS in 90 seconds.

Most Australian SMBs spend 3–5 hours on every quarterly BAS. You don't have to.

Free calculator · No account · No email required · Figures prepared, you lodge via ATO

Your quarterly figures

Enter amounts in AUD (GST-inclusive where marked). Empty fields are treated as zero.

All revenue collected this quarter, GST-inclusive

$

Assets bought this quarter: vehicles, equipment, property

$

Operating expenses: supplies, services, rent

$

Total wages paid to employees this quarter (before tax)

$

Tax you withheld from employee wages to remit to ATO

$

Your own prepayment toward annual income tax (set by ATO)

$

Prepared BAS figures

1A — GST on sales
$0.00
1B — GST on purchases
$0.00
Net GST (payable)
$0.00
W2 — tax withheld
$0.00
5A — PAYG instalment
$0.00
Total PAYG
$0.00
BAS total (payable to ATO)
$0.00

XIntelliSync is not a registered ATO Digital Service Provider.

This calculator prepares BAS figures only. Lodge via the ATO Business Portal or your registered tax agent. Double-check every figure against your accounting records before lodgement.

Step by step

How to prepare your BAS. Seven steps.

Every step links to the exact field in the calculator above.

  1. 1

    Register for GST

    If your annual turnover is $75,000 or more ($150,000 for non-profits), register for GST via ATO Business Portal.

  2. 2

    Track sales and purchases throughout the quarter

    Categorise every transaction with the correct GST code as it happens. Reconcile your bank feed regularly.

  3. 3

    Enter your quarterly totals

    Total sales (including GST) goes in G1. Capital purchases (including GST) in G10. Non-capital purchases in G11. PAYG withheld wages in W1, withholding amount in W2, PAYG instalment in 5A.

  4. 4

    Calculate net GST position

    The calculator divides sales by 11 for box 1A (GST collected) and divides purchases by 11 for box 1B (GST paid). Net GST is 1A − 1B. Positive means you owe; negative is a refund.

  5. 5

    Add PAYG amounts

    Total PAYG is W2 (tax withheld from employees) plus 5A (your PAYG instalment). Add this to net GST to get the BAS total owed or refunded.

  6. 6

    Review your prepared BAS figures

    Cross-check totals against your accounting records. Confirm every GST-inclusive figure is accurate to the cent.

  7. 7

    Lodge via ATO Business Portal or tax agent

    XIntelliSync does not lodge. Transfer the prepared figures to the ATO Business Portal at business.gov.au, or give them to your registered tax agent for lodgement.

BAS questions, answered.

What is a BAS (Business Activity Statement)?+
The Business Activity Statement is the report Australian businesses registered for GST lodge with the ATO each quarter (or month). It covers GST collected, GST paid, PAYG withholding, and PAYG instalments. Registration is required once annual turnover exceeds $75,000 ($150,000 for non-profits).
When is BAS due?+
Quarterly BAS deadlines: Q1 (Jul–Sep) due 28 October. Q2 (Oct–Dec) due 28 February. Q3 (Jan–Mar) due 28 April. Q4 (Apr–Jun) due 28 July. Monthly BAS lodgers follow a different schedule set by the ATO. An extra 2 weeks is typically granted when lodged through a registered tax agent.
How do I calculate GST on sales?+
Divide your total sales (including GST) by 11. Example: $11,000 in sales including GST = $1,000 GST collected. This is box 1A on the BAS form. The calculator above does this automatically.
How do I calculate GST on purchases?+
Divide your total purchases (including GST) by 11. Combine capital purchases (G10) and non-capital purchases (G11) eligible for GST credits. This is box 1B on the BAS form. The calculator computes this from your G10 and G11 inputs.
Does XIntelliSync lodge BAS with the ATO?+
No. XIntelliSync is not a registered ATO Digital Service Provider. This calculator and the BAS preparation agents prepare your figures and supporting records. You lodge via the ATO Business Portal or your registered tax agent. Every prepared BAS stays under your control until you authorise lodgement.
What is the difference between PAYG withholding and PAYG instalment?+
PAYG withholding (W1 + W2) is tax withheld from employee wages on your behalf and reported quarterly. PAYG instalment (5A) is your own prepayment toward your annual income tax liability, calculated by the ATO. Both appear on the same BAS form and are totalled together for payment.
What happens if I miss a BAS deadline?+
The ATO applies Failure to Lodge (FTL) penalties — approximately $313 per 28-day period overdue (2026 rates, one penalty unit = $313). General Interest Charge (GIC) also accrues on any unpaid tax from the due date. Lodging on time even if you cannot pay immediately avoids the FTL penalty.
The calculator is free. The automation is $97/mo.

The calculator doesn't lodge. You do.

The full XIntelliSync BAS preparation agent reads your live bank feed, categorises every transaction, flags GST exceptions, and prepares the BAS automatically — every quarter. You still lodge. The prep stops eating your Sundays. Included in every plan from $97/month AUD.

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Quarterly deadlines: Q1 · 28 Oct · Q2 · 28 Feb · Q3 · 28 Apr · Q4 · 28 Jul