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Module 09 — Legal, Tax & Business Setup
Quarterly BAS — The 4-Hour Ritual That Saves You from the ATO
11 min · text · Beginner
BAS quarter is not the four hours you spend on it. It is the year you spend not reconciling your books, then trying to reconstruct receipts the night before lodgement. The operators who treat BAS as a quarterly ritual lodge in 4 hours and pay correctly. The operators who treat it as an emergency lodge late, pay penalties, and burn weekend hours fighting Xero. Today: the 4-hour BAS ritual that runs on autopilot from quarter two onward.
What a BAS is
A Business Activity Statement (BAS) is the quarterly form you lodge with the ATO to report:
- GST collected on your AU sales (10% of GST-inclusive revenue × 1/11)
- GST paid on your AU business expenses (10% of GST-inclusive expense × 1/11)
- Net GST to remit (collected − paid). Positive = pay ATO; negative = ATO refund.
- PAYG instalments if applicable (income-tax pre-payment, ATO calculates from prior year)
Quarters are: Jul-Sep, Oct-Dec, Jan-Mar, Apr-Jun. Lodgement deadlines are usually 28 days after quarter end (so Sep quarter is due Oct 28). Late lodgement = A$330 minimum penalty + interest.
The 4-hour quarterly ritual
The structured ritual that runs in 4 hours flat:
Hour 1 — Reconcile Shopify. Pull a Shopify "GST/Tax report" for the quarter. This gives you total AU sales, total GST collected. Cross-check against Stripe payouts (Stripe also exports a tax-inclusive report). Numbers should match within A$50.
Hour 2 — Reconcile expenses in Xero. If you are running Xero (Module 17), every business expense is already coded with the GST flag. Run the "GST" report for the quarter. Look for outlier expenses: anything coded "GST-free" that should have GST, anything coded "GST" that should not (overseas supplier invoices, AliExpress under A