Non-dialable point

In conventional landline telephony, a non-dialable toll point or toll station was a lone station or line serving a rural subscriber many miles from the nearest central office. As it had no home telephone exchange and therefore no local calling area, all connections were obtained manually from the long distance operator.

These toll stations were one of multiple categories of non-dialable points which could only be reached with assistance from the inward operator at destination. Other non-dialable points included locations reachable only by some form of two-way radio and specific categories of manual service.

As manual services are replaced by automated infrastructure and satellite telephony now reaches the most distant points on the globe, truly non-dialable points are becoming rare.

To reach remote rural locations, telephone companies have been created with as little as one subscriber (the Methodist Episcopal Corporation, established in the 1940s to interconnect a Methodist church in Carmanville, Ontario to Bell Canada's long distance network, was taken over by Bell in 1970).

A similar service was provided in North America using toll stations or "ring downs", individual subscribers who were connected over many miles of landline directly to AT&T long distance with no local calling area. Reachable only with operator assistance, these served points like Deep Springs College in Deep Springs, California (whose telephone number for much of the 1980s remained "Deep Springs Toll Station #2"), far corners of the Nevada or California deserts and a few individual ranches in very remote corners of the Texas Panhandle. In Canada, regional incumbent local exchange carriers (such as Telus in Alberta, MTS in Manitoba or Bell Canada in Ontario and Quebec) provided operator assistance to complete inbound calls to non-dialable points.

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