47 C.F.R. § 69.131
To the extent the company makes contributions to the Universal Service Support Mechanisms pursuant to §§ 54.706 and 54.709 of this chapter and the non-price cap local exchange carrier seeks to recover some or all of the amount of such contribution, the non-price cap local exchange carrier shall recover those contributions through a charge to end users other than Lifeline users. The charge to recover these contributions is not part of any other element established pursuant to part 69. Such a charge may be assessed on a per-line basis or as a percentage of interstate retail revenues, and at the option of the local exchange carrier it may be combined for billing purposes with other end user retail rate elements. A non-price cap local exchange carrier opting to assess the Universal Service end-user rate element on a per-line basis may apply that charge using the "equivalency" relationships established for the multi-line business PICC for Primary Rate ISDN service, as per § 69.153(d) , and for Centrex lines, as per § 69.153(e) .
47 C.F.R. §69.131