BAS Preparation Checklist for Australian Small Business
The BAS does not have to be an evening of quiet dread. Whether it is your first quarter or your fortieth, the work breaks down into the same short list — and most of the pain comes from receipts that were never captured properly, not from the BAS itself. Here is the checklist, the deadlines, and where the numbers actually come from.
BAS deadlines at a glance
For quarterly lodgers, the activity statement for each quarter is due on the 28th of the month after the quarter ends:
| Quarter | Period | Due |
|---|---|---|
| Q1 | July – September | 28 October |
| Q2 | October – December | 28 February |
| Q3 | January – March | 28 April |
| Q4 | April – June | 28 July |
If a due date falls on a weekend or public holiday, the ATO generally allows the next business day, and lodgment through a registered tax or BAS agent typically buys extra time. Monthly GST lodgers have a different rhythm (the 21st of the following month). Confirm your own dates on the ATO website or with your agent — penalties for late lodgment are charged per 28-day period, per statement.
The checklist
1. Gather every receipt and invoice for the quarter
Everything: card receipts, emailed tax invoices, subscriptions, fuel, the lot. If a purchase is over $82.50 including GST, you need a valid tax invoice to claim the credit — the ATO is strict about this one. A Google Drive folder that receipts get photographed or emailed into as they happen turns this step from a shoebox archaeology dig into opening a folder.
2. Make sure each purchase is in your books with the right GST treatment
This is the heart of the BAS. Every purchase needs to be recorded as either GST-inclusive (you claim the credit) or GST-free/input-taxed (you don't). The classic mistakes:
- Claiming GST on GST-free purchases — fresh food, most bank fees, insurance stamp duty, council rates. If the receipt shows no GST line, don't estimate one.
- Missing the GST you could claim — small receipts that never got entered.
- Private-use purchases recorded fully as business. The portion that is personal doesn't belong on the BAS.
- Duplicated receipts entered twice — a speciality of re-typing by hand at 9pm.
3. Know which labels your numbers feed
You don't need to love the BAS form, but knowing where your numbers land helps you sanity-check:
- G1 — total sales, including GST
- 1A — GST on your sales (what you owe)
- G11 — non-capital purchases (most normal expenses)
- G10 — capital purchases (assets over the threshold)
- 1B — GST on your purchases (what you claim back)
The difference between 1A and 1B is what you pay (or get refunded). If you are registered on a cash basis — most small businesses are — these come from money actually received and paid during the quarter, not invoiced.
4. Reconcile before you lodge
Match your books against your bank and card statements for the quarter. Every uncoded bank line is either a missing purchase (see step 2) or a duplicate waiting to happen. This is also the moment to run Xero's or MYOB's GST reconciliation report and compare it against your receipts' GST totals — if your bookkeeping software says one thing and your receipts say another, find out why before the ATO asks.
5. Lodge and keep the evidence
Lodge through your accounting software (Standard Business Reporting), myGovID-linked Online services for business, or your registered agent. Then keep the records — generally five years — because a BAS is a claim, and claims get checked. Your Drive folder of receipts is the evidence trail; the cleaner it is, the shorter any conversation with the ATO.
Where BAS Buddy fits
BAS Buddy is the receipt side of this checklist, automated:
- Watches your Google Drive receipt folder (read-only) and extracts vendor, ABN, date, total, GST and line items from each document
- Flags low-confidence extractions so you review the doubtful few, not everything
- Gives you GST and spend totals per quarter, aligned to the BAS calendar, so the number you put against G11 and 1B comes from the receipts themselves
- Exports to Xero, MYOB or plain CSV so your books carry the same GST treatment the receipts showed
It does not lodge your BAS and does not give tax advice — the labels, the judgment calls and the lodgment stay with you or your agent. It removes the typing, not the responsibility.
The five-minute version
1. Receipts all in one folder as they happen
2. Purchases recorded with correct GST treatment
3. Bank reconciled for the quarter
4. GST totals cross-checked against receipts
5. Lodge by the 28th, records kept five years
Free during early access — connect Drive and see your quarter as clean numbers.