26 U.S.C. § 4251

(a) Tax imposed (1) In general There is hereby imposed on amounts paid for communications services a tax equal to the applicable percentage of amounts so paid. (2) Payment of tax The tax imposed by this section shall be paid by the person paying for such services. (b) Definitions For purposes of subsection (a)— (1) Communications services The term “communications services” means— (A) local telephone service; (B) toll telephone service; and (C) teletypewriter exchange service. (2) Applicable percentage The term “applicable percentage” means 3 percent. (c) Special rule For purposes of subsections (a) and (b), in the case of communications services rendered before November 1 of a calendar year for which a bill has not been rendered before the close of such year, a bill shall be treated as having been first rendered on December 31 of such year. (d) Treatment of prepaid telephone cards (1) In general For purposes of this subchapter, in the case of communications services acquired by means of a prepaid telephone card— (A) the face amount of such card shall be treated as the amount paid for such communications services, and (B) that amount shall be treated as paid when the card is transferred by any telecommunications carrier to any person who is not such a carrier. (2) Determination of face amount in absence of specified dollar amount In the case of any prepaid telephone card which entitles the user other than to a specified dollar amount of use, the face amount shall be determined under regulations prescribed by the Secretary. (3) Prepaid telephone card For purposes of this subsection, the term “prepaid telephone card” means any card or any other similar arrangement which permits its holder to obtain communications services and pay for such services in advance.