The incumbent local exchange carrier in 604 and 778 is Telus.

The main incumbent local exchange carrier is Bell Canada, plus some independent companies.

These are marketed by local exchange carriers, the phone companies created to compete with the Baby Bells.

Frontier is the sixth largest local exchange carrier in the United States.

In 1996 the following central office numbering plan was put in place by the incumbent local exchange carrier.

Sogetel is an incumbent local exchange carrier that serves multiple areas in Quebec.

It can sometimes call the business office of the local exchange carrier which owns or last leased the line, such as via 6-1-1.

The incumbent local exchange carrier in 780 is Telus.

Such companies are known as competitive local exchange carriers.

Bell Canada continues to be the incumbent local exchange carrier for London.