Beginning May 1, 2003, interstate telecommunication services originating or terminating and billed to an address in South Dakota are subject to the 4% state sales tax. However, the tax will not be applicable to (1) any 800 number or 800 service unless that service originates and terminates in South Dakota; (2) the sale of telecommunication services to a provider of telecommunication services; or (3) the sale of interstate telecommunication service to a certified call center with a valid exemption certificate. A call center is “any physical location where telephone calls are placed or received, for the purpose of making sales, marketing, customer service, or technical support.” (S.B. 63, signed by the Governor on 3/20/2003, effective 5/1/2003)