G1, 1A and 1B on your BAS, explained simply

The three GST figures most gig workers fill in each quarter.

G1 – Total sales

Everything your business earned in the quarter, including GST. For a rideshare driver that is what riders paid for your trips, before the platform's fee is taken out.

1A – GST on sales

The GST included in your sales. When a sale includes 10% GST, the GST part is one eleventh of the total: a $110 fare includes $10 GST.

1B – GST on purchases

The GST you can claim back on things you bought for your business, such as platform fees and the business share of fuel, servicing and your phone. These are called GST credits.

A worked example

Over a quarter, a driver has:

• Fares, including GST: $2,200. So G1 is $2,200 and 1A is $200.
• Business costs that include GST: platform fees of $440 and the business share of fuel of $220. That is $660 in total, so 1B is $60.

GST to pay is 1A minus 1B: $200 − $60 = $140. If 1B is bigger than 1A, the ATO refunds the difference.

Good to know

• The ATO form asks for whole dollars: you leave out the cents when you enter the figures.
• Your BAS can have other labels too, such as PAYG instalments. Check what your own BAS asks for.
• Use the sales and purchases for the dates in that quarter only, following the accounting method you chose (most gig workers use cash).

How GigTics helps

GigTics works out G1, 1A and 1B from your statements and receipts, shows exactly which records make up each figure, and gives you the whole-dollar amounts to enter.

General information only, not tax advice. Rules can change and every situation is different: check ato.gov.au or ask a registered tax or BAS agent. Updated 18 October 2026.