Hello there, @samuel green.
You can adjust the sales tax amount from the previous month then zero out the invoice sales tax amount for the next month. However, you'll need to check with your accountant for more guidance.
Here's how to adjust the sales tax amount you owe:
Once done, you can now manually adjust the invoice sales tax amount to zero. Here's how:
This way, the sales tax amount will not calculate for the next month. You can read this article for the detailed steps and information: Process Sales Tax Adjustment.
But as mentioned above, I still encourage seeking help from your accountant so he/she could guide you which to take base on your recording practice and business needs.
In case you need tips and related articles in the future, visit our QuickBooks Community help website for reference: QBDT Self-help.
Feel free to add a comment below if you have any other QuickBooks or sales tax questions. I'll be right here to help.