Hello Deanhowell,
If the regular payment you are making is for lodgements that have been recorded within QuickBooks Online, then just record the partial payments for the relevant BAS lodgement:
- Navigate to the GST centre
- Select the Record payment button next to the relevant BAS
- Input in the amount of the partial payment and the date of the payment
- Select Save
You will be able to match to these individual payments on the Banking screen.
However, if these payments are for a tax obligation not recorded in QuickBooks Online, I would advise speaking to your accountant or tax professional about how best to record it.
-Ken