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This is the list of original North American Numbering Plan area codes of 86 plan areas as defined by AT&T in 1947. In preparation for direct distance dialing, AT&T and the Bell System developed the North American Numbering Plan in the 1940s. The plan divided the United States and Canada into numbering plan areas (NPAs) and assigned a three-digit dialing prefix to each. Over the course of the decade following introduction of these routing codes, local subscriber numbers were standardized to seven digits. This included a three-digit central office prefix, dialed as the first two letters of the local exchange name and one digit, and the four-digit subscriber line number. The original numbering plan defined the second digit of all area codes as either ''0'' or ''1'', to distinguish them from the local telephone exchange prefixes, which were assigned digits ''2'' through ''9'' in the second position. Area codes with a middle digit ''0'' (zero, ten dial pulses) were assigned to plan areas that covered an entire state or province, while jurisdictions with multiple plan areas received area codes having ''1'' (one, a single pulse) in the second digit.〔http://www.theatlantic.com/technology/archive/2014/02/our-numbered-days-the-evolution-of-the-area-code/283803/〕 This permitted long distance calls to be dialed within the same area code as a seven digit subscriber number without the area code. The most prominent, frequently called population centers were assigned digit sequences with the shortest dial time on rotary dial telephones.〔(Area Code History ).〕 The dialing time was determined by the amount of rotation of the dial that was needed to dial each digit. Digits 1 to 9 produced the corresponding number of pulses, and 0 resulted in ten pulses. For example, New York City was assigned area code 212 (five pulses), Los Angeles 213 (six pulses), Chicago 312 (six pulses), and Detroit 313 (seven pulses), while the area code with the lowest number, 201, produced 13 pulses. Adjacent areas were generally assigned codes that were not easily confused with one another, to minimize wrong numbers. No codes of the form ''N00'', ''N10'' or ''N11'' occur in the original set, with N=2, 3, ..., 9. The series ''N00'' was used for non-geographic numbers, starting with intrastate toll-free 800-numbers in 1966.〔http://www.atlantatelephonehistory.info/part4.html〕 ''N10'' numbers were originally teletypewriter exchanges and ''N11'' remains reserved for information and emergency numbers. No codes were originally assigned to Alaska and Hawaii, as neither were US states at the time, or Puerto Rico.〔http://www.lincmad.com/map1947.html〕 Initially, the codes were used by long-distance operators for trunk calls while preparations proceeded for end-customer direct distance dialing. The first customer-dialed call using an area code was placed on November 10, 1951, from Englewood, New Jersey, to Alameda, California.〔(First direct-dial call )〕 Direct distance dialing was gradually implemented throughout the continent. By the mid-1960s, direct distance dialing was commonplace in large cities. ==Original area codes== * Area code 201 – New Jersey * Area code 202 – District of Columbia * Area code 203 – Connecticut * Area code 204 – Manitoba * Area code 205 – Alabama * Area code 206 – Washington * Area code 207 – Maine * Area code 208 – Idaho * Area code 212 – New York (New York City) * Area code 213 – California (Southern California, including Los Angeles) * Area code 214 – Texas (northeastern Texas, including Dallas/Fort Worth) * Area code 215 – Pennsylvania (southeastern Pennsylvania, including Philadelphia) * Area code 216 – Ohio (northeastern Ohio, including Cleveland) * Area code 217 – Illinois (central) * Area code 218 – Minnesota (except southeastern part of state) * Area code 301 – Maryland * Area code 302 – Delaware * Area code 303 – Colorado * Area code 304 – West Virginia * Area code 305 – Florida * Area code 306 – Saskatchewan * Area code 307 – Wyoming * Area code 312 – Illinois (Chicago metropolitan area) * Area code 313 – Michigan (southeast Michigan, including Detroit) * Area code 314 – Missouri (eastern Missouri, including St. Louis) * Area code 315 – New York (central upstate New York, including Syracuse) * Area code 316 – Kansas (southern half of Kansas) * Area code 317 – Indiana (northern two-thirds of Indiana, including Indianapolis) * Area code 319 – Iowa (eastern third of Iowa) * Area code 401 – Rhode Island * Area code 402 – Nebraska * Area code 403 – Alberta * Area code 404 – Georgia * Area code 405 – Oklahoma * Area code 406 – Montana * Area code 412 – Pennsylvania (western Pennsylvania, including Pittsburgh) * Area code 413 – Massachusetts (western Massachusetts, including Springfield) * Area code 414 – Wisconsin (southern and northeastern Wisconsin, including Milwaukee) * Area code 415 – California (northern/central California, including San Francisco and Sacramento) * Area code 416 – Ontario (southern portion from Cobourg to Kitchener, including Toronto) * Area code 418 – Quebec (eastern half of Quebec, including Québec City) * Area code 419 – Ohio (northwest Ohio, including Toledo) * Area code 501 – Arkansas * Area code 502 – Kentucky * Area code 503 – Oregon * Area code 504 – Louisiana * Area code 505 – New Mexico * Area code 512 – Texas (central and southern Texas, including Austin and San Antonio) * Area code 513 – Ohio (southwest Ohio, including Cincinnati) * Area code 514 – Quebec (western half of Quebec, including Montreal) * Area code 515 – Iowa (central Iowa, including Des Moines) * Area code 517 – Michigan (south-central portion of Lower Peninsula, including Lansing) * Area code 518 – New York (northeastern New York, including Albany) * Area code 601 – Mississippi * Area code 602 – Arizona * Area code 603 – New Hampshire * Area code 604 – British Columbia * Area code 605 – South Dakota * Area code 612 – Minnesota (southeastern portion, including Minneapolis) * Area code 613 – Ontario (all except a southern portion covering Oshawa-Toronto-Kitchener) * Area code 614 – Ohio (southeast, including Columbus) * Area code 616 – Michigan (Grand Rapids, Upper Peninsula, western portion of Lower Peninsula) * Area code 617 – Massachusetts (eastern Massachusetts, including Boston) * Area code 618 – Illinois (southern Illinois, including East St. Louis and Carbondale) * Area code 701 – North Dakota * Area code 702 – Nevada * Area code 703 – Virginia * Area code 704 – North Carolina * Area code 712 – Iowa (western third, including Sioux City) * Area code 713 – Texas (southeastern Texas, including Houston) * Area code 715 – Wisconsin (northern Wisconsin) * Area code 716 – New York (western New York, including Buffalo and Rochester) * Area code 717 – Pennsylvania (eastern half, except for the Delaware and Lehigh Valleys) * Area code 801 – Utah * Area code 802 – Vermont * Area code 803 – South Carolina * Area code 812 – Indiana (southern Indiana) * Area code 814 – Pennsylvania (northwestern and central Pennsylvania) * Area code 815 – Illinois (northern Illinois, except Chicago and Quad Cities) * Area code 816 – Missouri (northwestern Missouri, including Kansas City) * Area code 901 – Tennessee * Area code 902 – Nova Scotia, Prince Edward Island, New Brunswick * Area code 913 – Kansas (northern half of Kansas) * Area code 914 – New York (southern New York, including Long Island, but excluding New York City) * Area code 915 – Texas (western Texas, including El Paso) * Area code 916 – California (northern California, but not including Sacramento) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「List of original NANP area codes」の詳細全文を読む スポンサード リンク
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