What vat code do i use for posting opening balance adjustments? I am wanting an equivalent to sage's t9?

Hello Nicole welcome to Community.

I have looked into the T9 tax code for Sage and this would appear to work as out of scope VAT, whilst QuickBooks Online does not natively contain this code you can set up a custom vat code to behave in the same way I have put instructions below which will allow you to create a Out of Scope VAT code. We would always advise checking this with an accountant before creating or adding any codes to your QuickBooks.

1. Select the Taxes heading on the left of your dashboard.
2. Now select Edit VAT and then  Edit Rates.
3. Here you will be able to set the name of your desired code for example Out of Scope and select the rate 0%, this will need to be a liability account type.
4. You will see an option for Show tax amount on return line here you must select Net Value of Sales.

Please let us know if there is anything else we can help with.

Thanks,