FoderisSimpler BAS explained: G1, 1A and 1B for small businesses
If your business is registered for GST and turns over less than A$10 million, your business activity statement (BAS) is probably shorter than you think. Under Simpler BAS you report three GST figures: G1, 1A and 1B. This guide explains what goes into each one, how to work them out from your books, and when the BAS is due.
In short
- Simpler BAS is the default GST reporting method for businesses with a GST turnover under A$10 million.
- You report three labels: G1 Total sales, 1A GST on sales and 1B GST on purchases.
- G1 includes taxable, GST-free and input-taxed sales. You choose whether G1 includes GST and tick the box to say which.
- 1A is the GST you collected. 1B is the GST credits you can claim, backed by tax invoices where required.
- Report whole dollars only: no cents, no negative figures, no symbols.
- Quarterly BAS is due 28 October, 28 February, 28 April and 28 July. Lodging online or through a registered agent can give you more time.
Who can use Simpler BAS
The ATO says Simpler BAS is the default reporting method for small businesses with a GST turnover of less than A$10 million. You don’t need to apply. If your GST turnover is A$10 million or more, you must use full reporting, which adds labels such as G2 (export sales), G3 (other GST-free sales), G10 (capital purchases) and G11 (non-capital purchases).
There are a couple of edge cases. If your GST turnover is under A$10 million but your aggregated turnover (including connected businesses) is over A$10 million, or your main activity is making input-taxed supplies, you can choose either method. If you’re unsure which applies to you, check the current ATO guidance or ask your accountant.
Your reporting method is based on the GST turnover the ATO has on record. If your turnover moves across the A$10 million line, phone the ATO to update it.
G1: Total sales
G1 is the total of all the sales you made in the period. It is broader than people expect. According to the ATO’s Simpler BAS GST bookkeeping guide, G1 includes:
- Taxable sales: most sales of goods and services to Australian customers, plus sales of business assets.
- GST-free sales: for example most exports, including services provided to customers outside Australia, and certain food, health and education supplies.
- Input-taxed sales: for example residential rent and most financial supplies.
Money that isn’t a sale stays out. The bookkeeping guide lists items such as dividends received, loan principal, wages, superannuation and private items as not reported on the BAS for GST.
GST-inclusive or exclusive?
G1 is the one label where you choose. You can report it including GST or excluding GST, and you mark “Yes” or “No” in the box under G1 to say which. The ATO’s BAS instructions note that reporting G1 excluding GST is only available if you use the accounts method. Most small businesses report G1 including GST, which is simpler to check against your bank and Stripe records. Whichever you pick, stay consistent.
1A: GST on sales
1A is the GST included in your taxable sales for the period. For sales priced including GST at the standard 10% rate, the GST is one eleventh of the price. A A$110 sale includes A$10 of GST.
Only taxable sales contribute to 1A. GST-free and input-taxed sales appear in G1 but add nothing to 1A. If you gave refunds on taxable sales, the GST on those refunds reduces your GST on sales.
1B: GST on purchases
1B is the GST credits you can claim on business purchases. The ATO says you can claim a credit if, among other things, the purchase is for your business, the price included GST, and you have a tax invoice for purchases over A$82.50 (including GST). There is also a four-year time limit for claiming credits.
Things that commonly have no GST in the price include bank fees, wages, super, and purchases from suppliers who aren’t registered for GST. Overseas software subscriptions vary: some overseas suppliers charge Australian GST and some don’t, so check the invoice.
Cash or accrual: which period does it go in?
Your GST accounting method decides the period. On a cash basis, you report sales when you’re paid and claim credits when you pay. On a non-cash (accrual) basis, you generally report when you issue or receive an invoice, or when payment happens, whichever is earlier. For a business paid by card at checkout, the two often line up.
Worked example
A small software business on the cash basis has this quarter (all amounts in Australian dollars):
| Item | Amount | GST |
|---|---|---|
| Subscriptions to Australian customers | 22,000.00 | 2,000.00 |
| Refunds to Australian customers | 330.00 | 30.00 |
| Subscriptions to overseas customers (GST-free) | 8,450.00 | 0.00 |
| Bank interest received (input-taxed) | 12.40 | 0.00 |
| Purchases with GST (hosting, software, Stripe fees) | 3,861.50 | 351.05 |
| Purchases with no GST (bank fees, overseas software) | 940.00 | 0.00 |
Working it out, with G1 reported including GST:
- G1 = 22,000.00 minus 330.00 plus 8,450.00 plus 12.40 = 30,132.40, reported as 30,132.
- 1A = 2,000.00 minus 30.00 = 1,970.00, reported as 1,970.
- 1B = 351.05, reported as 351.
The business owes 1,970 minus 351, which is A$1,619 for the quarter.
Whole dollars and other formatting rules
The ATO’s instructions say to report whole dollars only: don’t show cents, don’t report negative figures, and don’t use symbols such as $ or minus signs. Keep the cents in your books; only the BAS form drops them. If a label would be negative (for example, refunds exceed sales), ask your accountant or the ATO how to report it.
Due dates
For quarterly reporters, the ATO’s due dates page lists:
| Quarter | Months | Due |
|---|---|---|
| 1 | July, August, September | 28 October |
| 2 | October, November, December | 28 February |
| 3 | January, February, March | 28 April |
| 4 | April, May, June | 28 July |
If a due date falls on a weekend or public holiday, you have until the next business day. If you lodge online you may be eligible for an extra two weeks for quarters 1, 3 and 4. Registered tax and BAS agents can also get later dates through the BAS agent lodgment program, subject to conditions. Quarter 2 gets no extra time because its due date already includes a one-month extension.
Monthly reporters have different dates, generally the 21st of the following month. Check the ATO page for your situation.
Questions
Does Simpler BAS change how much GST I pay?
No. It changes how much detail you report, not the GST itself. You still need accurate records of every sale and purchase, and you must keep them in case the ATO asks.
Do overseas sales go in G1?
Yes. GST-free sales, including most exports, are part of G1 Total sales. They just add nothing to 1A.
Can I claim GST on a purchase without a tax invoice?
For purchases over A$82.50 including GST, you need a tax invoice before you claim the credit. For smaller purchases, a receipt or other record is generally enough.
What if I make a mistake on a lodged BAS?
The ATO has rules for fixing errors, either on a later BAS or by revising the original, depending on the size and type of mistake. Check the current ATO guidance or ask your accountant before correcting it.
How Foderis helps
Foderis is an Australian accounting app for online and SaaS businesses. You import your bank file, confirm the AI-suggested categories, and Stripe sales and receipts flow in, so your Simpler BAS figures for G1, 1A and 1B are ready to copy into the ATO. It is hosted in Sydney and costs A$9 a month, with a 30-day free trial.
This is general information, not tax advice. Your situation may differ: check with your accountant or the ATO.