If you need to give your clients special tax rates or make them tax-exempt, you can adjust your store to meet this need by setting up tax rates specifically for different membership levels.
To set membership-specific tax rates:
Go to the Store Setup -> Taxes section of your store's Admin area to set up taxes as described here.
When configuring taxes, make sure the "Use the same tax rates for all user membership levels" option is disabled.
Create a new tax rate or edit an existing one specifying the required membership.
Be sure to save your changes.
A detailed description of the tax configuration process is available in the section Taxes.