Your first BAS ever: a checklist for newly registered sole traders
The first BAS is the one that takes a whole weekend, because everything about it is new: the period, the labels, what counts, what does not, and where the form even lives. The second one takes an hour, and by the fourth it is twenty minutes. This checklist gets you through the first one in order, with the traps that catch new registrants marked.
Updated 16 September 2026. General information only, not tax advice.
Before the quarter ends
- Confirm your registration date and reporting period. Log in to ATO online services and open Activity statements. Your first statement shows its period; if you registered on 12 August it will run 12 August to 30 September, and it is due 28 October like everyone else’s.
- Confirm your basis. You chose cash or accruals when you registered; most sole traders chose cash. Check under your registration details if you are not sure. See cash vs accruals.
- Charge GST from your registration date. Every taxable sale from that date should have 10% added and appear on a tax invoice. If you missed a few, you still owe the GST on them; the ATO treats the amount received as GST inclusive.
- Set aside one eleventh of every GST-inclusive payment as it arrives, in a separate account if you can. The BAS bill is then already funded.
Gathering the inputs
The bank statement for the period is the foundation. Download it as CSV or PDF from your bank for each business account (see how to export a bank statement). If you took cash or were paid into a personal account, list those receipts separately. Collect tax invoices for any purchase over $82.50 that you intend to claim GST on; a photo of the receipt is fine.
Upload the statement to FlowFi, or work through it in a spreadsheet. Each line needs a category and a GST decision: does this carry GST, and how much of it is business?
Working out the sales side
- G1 is every sale in the period, including GST, and including any GST-free sales. On a cash basis, that means the money that arrived in the period, not the invoices you dated in it.
- 1A is the GST you collected: one eleventh of your taxable sales.
- Report gross amounts. If a platform or agency deducted its fee before paying you, G1 is the gross sale and the fee is a purchase.
- Money that is not a sale stays out: a loan, a personal transfer in, a refund from a supplier, the GST refund from a previous period.
Working out the purchases side
1B is the GST on business purchases you can claim. Go line by line:
- Purchases with GST from Australian suppliers: claim one eleventh, at the business-use share.
- Bank fees, interest, wages, government fees, insurance stamp duty and most overseas subscriptions carry no GST. Nothing to claim. See GST on overseas subscriptions.
- Mixed-use items such as a phone or car: claim only the business percentage. See private use and business percentage.
- Assets you bought for the business, such as a laptop or tools: the GST is claimable in full (at the business share) on this BAS, even though for income tax the item may be written off or depreciated separately.
- Anything you cannot support with a tax invoice above $82.50: leave it out until you find the invoice.
The pre-registration question
If you bought equipment or stock in the months before you registered and still have it, some of that GST may be claimable on an early BAS. The rules depend on how long ago you bought it and whether it is still held for business use. It can be worth real money on a big purchase, so raise it with your accountant before your first lodgement rather than after.
Lodging and paying
Sign in to myGov, open the ATO, go to Activity statements and select the period. On the simpler BAS you enter G1, 1A and 1B and answer the question about whether G1 includes GST. Your first statement almost never carries a PAYG instalment; the ATO adds those after your next tax return. Review the summary, submit, and save the receipt number.
Pay by the same date using the payment reference number on the statement, by BPAY or card. If 1B is bigger than 1A the ATO refunds the difference into the account on file, so check that account is your current one. Full steps are in how to lodge your BAS online.
After lodging
Keep the lodgement receipt, the report from your software or spreadsheet, and the tax invoices behind 1B for five years. Note anything you were unsure about so you can ask your accountant at tax time. Then set up the next quarter now: upload each month’s statement as it arrives and the second BAS will be a review, not a rebuild.
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Frequently asked questions
My first period is only six weeks long. Is that right?
Yes. The first statement runs from your registration date to the end of the quarter. It is due on the normal date for that quarter, and the next one covers a full three months.
I registered but had no sales in the first period. Do I still lodge?
Yes. Lodge with zeros, or with just your purchases at 1B if you bought things for the business, in which case you will get a refund of that GST.
Do I need an accountant for my first BAS?
Not necessarily. Many sole traders prepare the figures in software and lodge themselves. A one-off review of your first statement by an accountant or BAS agent is a sensible middle ground if you are unsure about pre-registration purchases or mixed-use items.
General information only, not tax advice. Check your own situation with a registered tax agent or the ATO.
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