In telecommunications, a long-distance call (U.S.) or trunk call (also known as a toll call in the UK ) is a telephone call made to a location outside a defined local calling area. Long-distance calls are typically charged a higher billing rate than local calls. The term is not necessarily synonymous with placing calls to another telephone area code.

Long-distance calls are classified into two categories: national or domestic calls which connect two points within the same country, and international calls which connect two points in different countries. Within the United States there is a further division into long-distance calls within a single state (intrastate) and interstate calls, which are subject to different regulations (counter-intuitively, calls within states are usually more expensive than interstate calls). Not all interstate calls are long-distance calls. Since 1984 there has also been a distinction between intra-local access and transport area (LATA) calls and those between different LATAs, whose boundaries are not necessarily state boundaries.

Before direct distance dialing (DDD), all long-distance calls were established by special switchboard operators (long-distance operators) even in exchanges where calls within the local exchange were dialed directly. Completion of long-distance calls was time-consuming and costly as each call was handled by multiple operators in multiple cities. Record keeping was also more complex, as the duration of every toll call had to be manually recorded for billing purposes.

In many less-developed countries, such as Spain, Mexico, Brazil, and Egypt, calls were placed at a central office the caller went to, filled out a paper slip, sometimes paid in advance for the call, and then waited for it to be connected. In Spain these were known as locutorios, literally "a place to talk". In towns too small to support a phone office, placing long-distance calls was a sideline for some businesses with telephones, such as pharmacies.

In some countries, such as Canada and the United States, long-distance rates were historically kept artificially high to subsidize unprofitable flat-rate local residential services. Intense competition between long-distance telephone companies narrowed these gaps significantly in most developed nations in the late 20th century.

The cost of international calls varies dramatically among countries. The receiving country has total discretion in specifying what the caller should be charged (by the originating company, who in a separate transaction transfers these funds to the destination country) for the cost of connecting the incoming international call with the destination customer anywhere in the receiving country. This has only a loose, and in some cases no, relation to the actual cost. Some less-developed countries, or their telephone company(s), use these fees as a revenue source.

History

On August 10, 1876, Alexander Graham Bell made a call via the telegraph line between Brantford and Paris, Ontario, eight miles (thirteen kilometres) distant. This test was said by many sources to be the "world's first long-distance call". This test certainly proved that the telephone could work over long distances, at least as a one-way call.

Following a major flood in 1877, the president of the Chesapeake and Ohio Canal, Arthur Pue Gorman, hired J. Frank Morrison to build a communications line. The initial plan was for a telegraph, but due to rapid advances in technology, the project was changed to a telephone system which promised lower operating costs. Morrison's construction gangs worked through the summer of 1879, completing a line that stretched over 180 miles from Georgetown to Cumberland, Maryland. The system used forty-eight Edison Universal TelephonesEdison Universal Telehones - Western Union's advanced carbon transmitter model, which used a small button of compressed carbon to convert sound into a much stronger and clearer electrical signal than Alexander Graham Bell's original liquid transmitter design. This superior technology was essential for making long-distance telephone lines. stationed at intervals along the route, and was considered a pioneering achievement, the world's first commercial long distance telephone service.

In 1891, AT&T built an interconnect telephone network, which reached from New York to Chicago, the technological limit for non-amplified wiring. Users often did not use their own phone for such connections, but made an appointment to use a special long-distance telephone booth or "silence cabinet" equipped with 4-wire telephones and other advanced technology. The invention of loading coils extended the range to Denver in 1911, again reaching a technological limit. A major research venture and contest led to the development of the audion—originally invented by Lee De Forest and greatly improved by others in the years between 1907 and 1914—which provided the means for telephone signals to reach from coast to coast. Such transcontinental calling was made possible in 1914 but was not showcased until early 1915, as a promotion for the upcoming Panama–Pacific International Exposition in San Francisco in the spring of the same year.

On January 25, 1915, Alexander Graham Bell ceremonially initiated the first transcontinental telephone call from 15 Dey Street in New York City, which was received by his former assistant Thomas A. Watson at 333 Grant Avenue in San Francisco. This process, nevertheless, involved five intermediary telephone operators and took 23 minutes to connect by manually patching in the route of the call.

On November 10, 1951, the first direct dial long-distance telephone call in North America was placed from Mayor M. Leslie Denning of Englewood, New Jersey to Mayor Frank Osborne of Alameda, California via AT&T's Bell System.The mosquito crusades: a history of ... – Gordon M. Patterson – Google Books The ten-digit call (seven digits plus a three-digit area code) was connected automatically within 18 seconds.1951: First Direct-Dial Transcontinental Telephone Call, AT&T Inc. Accessed June 8, 2007. Quote: "Nov. 10, 1951: Mayor M. Leslie Downing of Englewood, N.J., picked up a telephone and dialed 10 digits. Eighteen seconds later, he reached Mayor Frank Osborne in Alameda, Calif. The mayors made history as they chatted in the first customer-dialed long-distance call, one that introduced area codes."

The first subscriber trunk dialing in the United Kingdom was deployed December 5, 1958 with Elizabeth II placing a call from Bristol to Edinburgh.

International calling

After World War II, priority was given by AT&T in the US and the various PTT entities in Europe to automating switching on the toll networks in their respective countries (initially for Operator Toll Dialing). Thus, when TAT-1 was opened for service, it was connected to international gateway offices at White Plains, NY, and London that were already automated for domestic calls. These were designed to be able to automatically switch outward and inward international circuits as soon as common signalling standards (and political considerations) could be negotiated. However, at the outset, to set up an international call, multiple operators were required: one to originate the call and one at each national gateway to complete a call via either ringdown to a local operator or Operator Toll Dialing.

International direct dialling from London to Paris was first offered in March 1963, with Amsterdam following by the end of 1963. Simultaneously, operator-dialed transatlantic calling began March 30, 1963 with the originating international operator in Western Europe or the US able to complete calls to the terminal station without further operator assistance via the gateway exchanges at White Plains and London. Operator-dialed transpacific calling to Hawaii, Japan, and Australia began with the completion of the Commonwealth Pacific Cable System (COMPAC)cable, also in 1963.

By mid-1968, transatlantic cable capacity had increased to the point where scheduling calls between Western Europe, the UK, and the US was no longer necessary and calls were completed on demand. Transatlantic international direct dialing between New York City (212 area code) and London (01 STD code) was introduced in 1970, with service extended to the whole of the US and the six largest UK cities in 1971.

Collect/reverse-charge calling Various schemes were devised to allow large organisations to automatically accept collect calls, where the recipient pays long-distance charges for any call from a predefined area. A Zenith number in the late 1950s required an operator manually determine the destination number from a printed list; the 1967 Wide Area Telephone Service introduced the first automated toll-free telephone numbers, terminated on special fixed-rate trunks. By the 1980s, computerisation of the system allowed British Telecom "Linkline" 0800 freephone numbers and AT&T +1-800- toll-free numbers to be controlled by a database and terminated virtually anywhere with each inbound call itemised and billed individually. This smart network was further refined to provide toll-free number portability in the 1990s.

Technical advances Improvements in switching technology, the deployment of high-capacity optical fibre and an increase in competition substantially lowered long-distance rates at the end of the 20th century. Using the Internet, the distinction between local and long-distance communication is fading to the point where an Internet call from the United States to Beijing carries a lower wholesale cost than a domestic landline call to a rural independent in small-town Iowa.

"Calling Packages" and "Internet Phoning" (VOIP) were cited as a contributing factor towards "Swiftly Ending a High-Cost Category" in 2004.

Example of manual operator call

In the radio series Dragnet, Sgt. Joe Friday (Jack Webb) places an operator assisted person-to-person long-distance call to a number reached via a manual switchboard in Fountain Green, Utah, a town of several hundred people served by an independent telephone company. In the call, Friday calls a long-distance operator in Los Angeles and gives the name and number of the called party. The operator then calls a rate-and-route operator, who responds that the call should be routed through Salt Lake City and Mount Pleasant, Utah, and that the rate-step for the call is 140. The long-distance operator would mark her ticket with that rate-step, and could use it to quote the rate from her rate table, in terms of the first three minutes and each additional minute, if the caller requested the toll.

The Los Angeles long-distance operator then plugs into a direct trunk to the Salt Lake City inward operator and asks her for Mount Pleasant; the Salt Lake operator rings Mount Pleasant, where the Los Angeles operator asks for Fountain Green. The Mount Pleasant operator rings Fountain Green, and the Los Angeles operator gives the Fountain Green operator the number and name of the called party in Fountain Green. The Fountain Green operator rings the number, 14R2, a party line where a specific ringing pattern summons the second subscriber on the shared line. A man answers; the Los Angeles operator asks for the called party and states that Los Angeles is calling.