HI Brendanil,
Thanks for posting in the Community!
GST figures in your Business Activity Statements (BAS) come from transactions with a tax code. If you're not GST registered, nothing appears in your BAS in QuickBooks Online. It's best to consult the ATO or an accountant for guidance on filing your tax return.
Furthermore, if you've turned on the GST in your account, you can mark your transactions with GST free. There will be no tax calculated on the transaction but it will be reported in your BAS. As compared to Out of scope tax code the transaction will not be included in your BAS.
Check this link for your reference: Lodge your BAS or IAS in QuickBooks Online.
Drop a comment below if you have more questions about lodging BAS in QuickBooks Online. I'm around to help you.
