Enable Zip2Tax to calculate tax based on postal code: Check this checkbox to enable the zip2tax service. When enabled and a valid state, postal code, or country matches to charge sales tax, a query will be sent to zip2tax using their Lookup XML service to obtain a tax rate for the customer's provided postal code.

Zip2Tax Username: Enter your username provided to you by Zip2Tax.

Zip2Tax Password: Enter your password provided to you by Zip2Tax.