Client is zero-rated medical how do I disable sales tax, don't want to see it in the GL?

Hi there, 

Welcome back to the Community. I'd be happy to assist with showing you how to disable a sales tax code for a client. 

As you know, once you've activated the sales tax feature, you won't be able to turn it off. To make sure you're not collecting taxes on a customer, you'll need to follow the steps below:

1.     Go to the Sales tab and click Customers.
2.     Click the Edit tab.
3.     Open the Tax info folder and select the Default tax code.
4.     Hit Save.

Going forward, there won't be any taxes applied to the customer's invoice. 

If you have other questions, don't hesitate to comment below. I'll be on standby.:)