Thanks for reaching out. I know how convenient it is to have control over the settings in your account. I'll be happy to assist you with this.
Completely deleting a tax rate is not currently an option, as this could negatively impact your historical tax returns. To ensure data integrity in QuickBooks Online, the best way to handle a tax rate you aren't using is to make it inactive. Here's how to do that.
To make a sales tax code inactive
Select Taxes from the left menu
Select Sales Tax at the top
Select Manage sales tax
On the Tax agencies tab, locate the tax agency associated with the sales tax rate you wish to make inactive
Select Make inactive in the Actions column next to the rate you wish to make inactive
You'll know the sales tax rate has been deactivated when you see Make active in the Actions column for that sales tax rate
Doing this hides the rates from the tax selection menu on all transactions. If you'd benefit from additional options in managing inactive tax rates, feel free to submit feedback directly to our engineers through the Gear icon > Feedback. Your comments are crucial in driving innovation to offer the best QuickBooks experience we can.