One penny

[Conan71]

Well, that should be very simply illegal, nationally, and banned as part of trade treaties as well.

I'm sure they will get right on that just as soon as they ban lobbying.

[nathanm]

Have you tried it?  My former company did.  It was a nightmare to rollout and maintain.  Remember, municipalities and counties change rates often.

I have; it worked fine. There are (free, yet still certified!) web services that will calculate the tax for you, and even remit the necessary tax and forms to streamlined states. There is no need to maintain your own database.

Edited to add: Free of cost on the service provider end, who gets paid on commission by the SSTUA states. Obviously, any integration with other software that is required costs the business some money for that service.