A local telephone company which held the regional monopoly on landline service before the market was opened to competitive local exchange carriers (CLEC) with the Telecommunications Act of 1996, or the corporate successor of such a firm. The ILEC typically owns the legacy telecommunications infrastructure (copper, fiber, switching, and colocation facilities) to which it must provide competitive access and interconnection.

The original ILECs included GTE Corp. and the former Regional Bell Operating companies (known as RBOCs, or the “Baby Bells”), which were formed when the American Telephone Telegraph Company (now ATT) was broken up in 1983.

An incumbent local exchange carrier is a local exchange carrier (LEC) in a specific area that:

  • on the date of enactment of the Telecommunications Act of 1996, provided telephone exchange service

  • on the date of enactment, was deemed to be a member of the National Exchange Carrier Association pursuant to the Code of Federal Regulations (C.F.R) Title 47, section 69.601(b).[1]

  • or is a person or entity that, on or after such date of enactment, became a successor or assignee of a member described in the previous bullet.

The Federal Communications Commission (FCC) may, by rule, provide for the treatment of an LEC (or class or category thereof) as an ILEC if:

  • such carrier occupies a position in the market for telephone exchange service within an area that is comparable to the position occupied by a carrier described previously

  • such carrier has substantially replaced an ILEC described previously

  • such treatment is consistent with the public interest, convenience and necessity