Thank you for joining the thread, @sanman1. We appreciate your effort in sharing your concerns about the sales tax feature. Let me share additional information to help clear things out. 

The sales tax in QuickBooks Online (QBO) automatically calculates the total tax rate for each sale based on the following:

• Your customer's tax-exempt status
• Where you sell and where you ship
• What you sell

The "based on location" is your customer tax status because tax-exempt rules are not the same everywhere, QBO will sometimes need to calculate sales tax for tax-exempt customers. 

You may also refer to this article about how sales tax works in QBO: Learn how QuickBooks Online calculates sales tax.

Furthermore, QuickBooks Online (QBO) only depends on the data provided to them. If you integrate the BigCommerce platform into QBO, you might want to check the sales tax configuration from the BigCommerce. 

For more detailed information, you may check this article about the integration of BigCommerce: Integrate BigCommerce and QuickBooks Online using OneSaas.

In addition, I'll add this article when you want to memorize reports: Memorize reports in QuickBooks Online.

Feel free to reach us out again, if you have further concerns.