A toll-free telephone number or freephone number is a telephone number that is billed for all arriving calls. For the calling party, a call to a toll-free number from a landline is free of charge. A toll-free number is identified by a dialing prefix similar to an area code. The specific service access varies by country.
The features of toll-free services have evolved as telephone networks have evolved from electro-mechanical call switching to computerized stored program controlled networks.[1]
Originally,[when?] a call billed to the called party had to be placed through a telephone company operator as a collect call, often long-distance. The operator had to secure acceptance of the charges at the remote number, or even transfer that decision to a long-distance operator, before manually completing the call.
Some large businesses and government offices received large numbers of collect calls, which proved time-consuming for operators and the callers.
Prior to the development of customer-dialed toll-free service many telephone companies provided the service by operator assistance for telephone subscribers without dial telephones (manual service).
Operator-assisted toll-free calling included the Zenith number service introduced in the 1930s in the U.S. and Canada, as well as the manual 'Freephone' service introduced by the British Post Office in 1960.[2][3]