Ind. Code § 6-2.5-12-10

Sec. 10. As used in this chapter, "post paid calling service" means the telecommunications service obtained by making a payment on a call by call basis either through the use of a credit card or payment mechanism such as a bank card, travel card, credit card, or debit card, or by charge made to a telephone number that is not associated with the origination or termination of the telecommunications service. A post paid calling service includes a telecommunications service, except a prepaid wireless calling service, that would be a prepaid calling service except it is not exclusively a telecommunications service.