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'{{Redirect|NANPA|other uses|Nanpa (disambiguation)}} {{About|the numbering plan|a list of area codes under the plan|List of North American Numbering Plan area codes}} The '''North American Numbering Plan''' ('''NANP''') is an integrated [[telephone numbering plan]] that encompasses 25 countries and territories primarily in North America and the Caribbean. The NANP is a standardized system of [[numbering plan area]]s (NPA) using [[telephone number]]s consisting of three-digit area code, a three-digit central office code, and a four-digit station number. Through this plan, [[telephone]] calls can be directed to particular regions of the larger NANP public switched telephone network ([[Public switched telephone network|PSTN]]), where they are further routed by the local networks. The NANP is administered by the ''North American Numbering Plan Administration'' (''NANPA''), a service operated by [[Neustar]] corporation. The [[international calling code]] for the NANP is ''1''. Not all North American countries participate in the NANP. ==History== The North American Numbering Plan was developed in the 1940s in the [[Bell System]] serving the United States and Canada with an unorganized system of many differing numbering plans based on the needs of the individual local telephone operating companies.<ref name=bstj1952>W.H. Nunn, ''Nationwide Numbering Plan'', Bell System Technical Journal, Vol. 31 Issue 5, pp.851 (1952)</ref> It was first implemented in 1951 with the introduction of [[direct distance dialing]] (DDD). Today, under an independent administration provided by [[Neustar]] (formerly [[Lockheed Martin|Lockheed Martin IMS]]), the system has grown to include the [[United States]] and its [[Insular area|territories]], [[Canada]], [[Bermuda]], and 17 nations of the [[Caribbean]].<ref>[http://www.nanpa.com/about_us/index.html NANPA : North American Numbering Plan Administration – About Us<!-- Bot generated title -->]</ref><ref>{{cite news|last=MEHTA|first=STEPHANIE N.|title=The Kennedy Space Center Acquires A New Area Code: 3-2-1, as in Blast Off|newspaper=Wall Street Journal|date=1999-02-26}}</ref> The term is also used, by [[metonymy]], to refer to the geographic area in which that plan has been implemented. For the introduction of direct customer dialing of long-distance telephone calls, the Bell System set out to unify the various numbering plans in existence at the time. [[Area codes 201 and 551|Area code 201]] was the first implemented under the plan.<ref>[http://scholar.lib.vt.edu/VA-news/VA-Pilot/issues/1995/vp951101/11010459.htm "Now You Can Call, If Your Calls Don't Work Some Business Lines Aren't Set Up To Call To New Area Codes."], ''[[The Virginian-Pilot]]'', November 1, 1995. Accessed June 8, 2007. "When the first area code, 201, was introduced in New Jersey in 1951, phone-numbering experts thought there would be enough codes with a middle digit of ''0'' or ''1'' to last well into the next century."</ref> At the request of the [[United Kingdom|British]] [[Colonial Office]], the numbering plan was first expanded to [[Bermuda]] and the [[British West Indies]], including [[Trinidad and Tobago]]), because of their historic telecommunications administration through [[Canada]] as parts of the [[British Empire]], and their continued associations with Canada, especially during the years of the telegraph and the [[All Red Line]] system. Despite its name, not all North American countries participate in NANP. [[Mexico]], the [[Central America]]n countries and some [[Caribbean]] countries ([[Cuba]], [[Haiti]], and the [[French Caribbean]] are not part of the system. The only Spanish-speaking sovereign nation in this plan is the [[Dominican Republic]]. Mexican participation was planned, but implementation stopped after two area codes were put into use ([[Mexico City]] and northwestern Mexico); these ended in 1991 when Mexico withdrew from the NANP. Dutch-speaking [[Sint Maarten]] joined the NANP in September 2011.<ref name="Sint Maarten delay"/> [[Saint Pierre and Miquelon]] (+508) and [[Greenland]] (+299), both North American possessions of [[European Union]] nations, use non-NANP codes which are independent of their respective home countries (+33 [[France]] and +45 [[Denmark]]). At first, area codes were used only by long-distance operators; the first customer-dialed calls using area codes occurred on November 10, 1951, when the first directly dialed call was made from [[Englewood, New Jersey|Englewood]], New Jersey to [[Alameda, California|Alameda]], California.<ref>[http://www.corp.att.com/attlabs/reputation/timeline/51trans.html 1951: First Direct-Dial Transcontinental Telephone Call], [[AT&T Corporation]]. Accessed June 8, 2007. "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."</ref> Direct dialing was gradually instituted throughout the country, and by the mid-1960s, it was commonplace in cities and most larger towns. Originally there were only [[Original area codes|86 codes]], with the biggest population areas getting the numbers that took the shortest time to dial on [[rotary telephone]]s.<ref>[http://www.area-codes.com/area-code-history.asp Area Code History]. Accessed January 4, 2009. "The rationale for this 'low number/high population' scheme was based on the fact that phones had rotary dials in those days. Lower numbers resulted in shorter 'dial pulls' so it was reasoned that the regions with the most people in them should require the least 'work' to call." The digit 0 represented 10 clicks.</ref> Thus, five largest cities based on 1950 US Census population received some of the "shortest" codes: [[New York City]] was given 212, [[Chicago]] 312, [[Los Angeles]] 213, [[Detroit]] 313, [[Philadelphia]] 215; while four areas received the then-maximum number of 21 clicks: [[South Dakota]] (605), [[North Carolina]] (704), [[South Carolina]] (803), and the [[Maritimes|Maritime Provinces]] of Canada (902). Additionally, in the original plan a middle digit of '''0''' indicated that the area code covered an entire state/province, while area codes with a middle digit of '''1''' were assigned to jurisdictions that were divided into multiple area codes.<ref>{{cite web |url=http://www.research.att.com/evergreen/about_us/tech_timeline.html?fbid=G8k7IXVYM6x |title=First Direct-Dial Transcontinental Telephone Call > 1950s > 1951 |author=admin |authorlink= |coauthors= |year=2012 |work= |publisher=AT&T Labs Research |location= |page= |pages= |at= |language= |trans_title= |format= |archiveurl= |archivedate= |deadurl= |accessdate=June 12, 2012 |quote=Determined to build a better system, an AT&T Engineering Department team investigated using a single set of short codes to divide North America into unique calling areas. The teams L. K. Palmer and W. H. Nunn concluded that a three-digit code - 2-to-9 as the first digit, the second number always 1 or 0 - produced a set of unique area codes with room for growth. Back then, a local phone number started with an exchange name followed by numbers, such as "Murray Hill 5." Since there were no letters above 1 or 0 on the dial, no phone numbers used a 1 or 0 in the first two pulls of the dial. Thus, equipment could distinguish long distance from local calls. The team assigned area codes with a middle digit of 1 to states needing multiple area codes and area codes with a middle digit of 0 to the rest. |ref= |separator= |postscript=}}</ref> At first, area codes were all in the form ''NYX'', where ''N'' is any number 2–9, ''Y'' is 0 or 1, and ''X'' is any number 1–9 (if ''Y'' is 0) or any number 2–9 (if ''Y'' is 1). The restriction on ''N'' saves 0 for calling the operator, and 1 for signaling a long-distance call. The restriction on the second digit, limiting it to 0 or 1, was designed to help telephone equipment recognize the difference between a three-digit "area code" (with 0 or 1 as the second digit) and the three-digit "exchange" prefix (which had avoided 0 or 1 for the second digit, because of restrictions in existing switching equipment). For example, when a caller dialed "202-555-1212", the switching equipment would recognize that "202" was an area code because of the middle 0, and route the call appropriately. If a caller were to dial 345-6789, the 4 would cause the number to be recognized as a long-distance number within the area and routed as such, without waiting for the caller to finish dialing. In the late 1980s and early 1990s, NANPA (then still part of Bellcore, which is now [[Telcordia Technologies]]) began to urge and later require all long-distance calls within each area to be prefixed with the digit 1 to distinguish them from local calls, so that badly needed prefixes with 0 or 1 in the middle could be assigned to local [[telephone exchange]]s. Also, since it had nearly run out of area codes using the above formula, it allowed the assignment of area codes using the form ''N10'', such as 210 in the [[San Antonio]], Texas, area and 410 in eastern [[Maryland]]. Therefore, someone calling from San Jose to Los Angeles before the change would have dialed 213-555-1234 and after the change 1-213-555-1234, which then allowed 213 to be used as an exchange prefix in the San Jose area. Until 1991, calls to some areas of [[Mexico]] from the [[United States]] and [[Canada]] were made using NANP area codes, but Mexican participation in the NANP was discontinued in favor of the general international format, using country code +52 instead. Area code 905 (formerly Mexico City) was re-assigned to a split of area code 416 (the [[Greater Toronto Area]]); area code 706 (formerly northwest Mexico) was reassigned to northern [[Georgia (U.S. state)|Georgia]], surrounding the [[Atlanta]] region which retained 404; and area code 903, which also served a small portion of northern Mexico, was reclaimed and later reassigned to [[Area codes 430 and 903|northeastern Texas]] when it split from [[area code 214]]. ==Numbering system== The NANP number format, including the [[E.164]] country calling prefix, can be summarized in the notation +1-NPA-NXX-xxxx. {| class=wikitable ! Component ! Name ! Number ranges ! Notes |- |'''[[List of country calling codes|+1]]''' |[[International Telecommunication Union|ITU]] country [[List of country calling codes|calling code]] | |"1" is also the usual [[trunk code]] for accessing long-distance service between NANP numbers. In an intra-NANP context, numbers are usually written without the leading "[[E.123|+]]" |- |'''[[List of North American Numbering Plan area codes|NPA]]''' |Numbering Plan Area Code |Allowed ranges: [2–9] for the first digit, and [0-9] for the second and third digits. When the second and third digits of an area code are the same, that code is called an easily recognizable code (ERC). ERCs designate special services; e.g., 888 for toll-free service. The NANP is not assigning area codes with 9 as the second digit.<ref>[http://www.nanpa.com/area_codes/index.html NANP NPA rule]</ref> |Covers Canada, the United States, parts of the Caribbean Sea, and some Atlantic and Pacific islands. The area code is often enclosed in parentheses. |- |'''[[NXX]]''' |Central Office (exchange) code |Allowed ranges: [2–9] for the first digit, and [0–9] for both the second and third digits (however, the third digit cannot be "1" if the second digit is also "1"). |Often considered part of a subscriber number. The three-digit Central Office codes are assigned to a specific CO serving its customers, but may be physically dispersed by redirection, or forwarding to mobile operators and other services. |- |xxxx |Subscriber Number |[0–9] for each of the four digits. |This unique four-digit number is the subscriber number or ''station code''. |} For example: * 234-235-5678 is valid * 234-911-5678 is invalid, because the exchange code cannot be in the form N11. * 123-234-5678 is invalid, because NPA cannot begin with 0 or 1 * 291-234-5678 is valid. The [[country calling code]] for the NANP is +1. In international format, an NANP number should be listed thus: {{gaps|+1|301|555|0100}} (example using the [[Original area codes|original area code]] for Maryland). The trunk prefix code for direct-dialed long-distance in the NANP is also 1. Each three-digit area code may contain up to 7,919,900 unique phone numbers: *NXX may begin only with the digits [2–9], providing a base of 8 million numbers: ( 8 x 100 x 10000 ) . *However, the last two digits of NXX cannot both be 1, to avoid confusion with the [[N11 code]]s (subtract 80,000). *Despite the widespread usage of NXX "555" for fictional telephone numbers&nbsp;— see [[555 (telephone number)]]&nbsp;— today, the only such numbers specifically reserved for fictional use are "555-0100" through "555-0199", with the remaining "555" numbers released for actual assignment as information numbers (subtract 100). *Several other NXX prefixes are generally not assigned: the home area code(s), adjacent domestic area codes and overlays, area codes reserved for future relief nearby, industry testing codes (generally NXX 958 and 959) and special service codes (such as NXX 950 and 976). ==Expansion== Canada and the United States have experienced rapid growth in the number of area codes, particularly between 1990 and 2005. There are two main reasons for this. First, there is the increasing demand for telephone services (particularly resulting from widescale adoption of [[fax]], [[modem]], and [[mobile phone]] communications). The second and more important reason is the telecom deregulation of local telephone service in the US beginning in the early to mid-1990s. At that time, the Federal Communications Commission began allowing telecommunication companies to compete with the [[incumbent local exchange carrier]] (usually by forcing the existing monopoly service provider to lease infrastructure to other local providers who then resold the service to consumers). However, because of the original design of the numbering plan and telephone switching network that assumed only a single provider, number allocations had to be made in 10,000-number blocks. Thus, whenever a new local service provider entered a given market, it would be allocated 10,000 numbers by default, even if the provider only obtained a few customers. As more companies began requesting numbering allocations, this caused many area codes to begin exhausting their supply of available numbers (code "in jeopardy" in telecom jargon), and additional area codes were needed. In reality, many of the new telecom ventures were not successful; while the number of area codes started increasing rapidly, this did not necessarily translate to a much larger number of actual telephone subscribers as large blocks of numbers lay unassigned to any "real" subscribers because of the 10,000-number block allocation requirement. When these telecom ventures were merged or bought or liquidated, their blocks went to the successor or went unused. No regulatory mechanism existed to reclaim and reassign these underutilized blocks. In general, area codes were added either as "splits" (in which an area code was divided into two or more regions, one retaining the older area code and the other area(s) receiving a new code), or "[[overlay plan|overlay]]s", in which multiple codes are assigned to the same geographical area. Subtle variations of these techniques have been used as well, such as "dedicated overlays", in which the new overlaid code was reserved for a particular type of service, such as cellular phones and pagers (the only true example of this was area code 917 in New York City), and "concentrated overlays", in which a part of the area retained a single code while the rest of the region received an overlay code. Area codes of the form N10, originally reserved for AT&T's [[Teletypewriter eXchange]] service, were transferred to Western Union in 1969 and were freed up for other use in 1981 after conversion to [[Telex|Telex II]] service was complete. These eight "new" area codes were used for telephone area code splits in the late 1980s and early 1990s, as all other area codes under the original plan had been consumed. After the remaining valid area codes were used up by expansion, in 1995 the rapid increase in the need for more area codes (both splits and overlays) forced NANPA to allow the digits 2 through 8 to be used as a middle digit in new area code assignments, with 9 being reserved as a "last resort" for potential future expansion. At the same time, local exchanges were allowed to use 1 or 0 as a middle digit. The first area codes without a 1 or 0 as the middle digit were [[area code 334]] in Alabama and [[area code 360]] in Washington, which both began service on January 15, 1995. This was quickly followed by [[area code 520]] serving Arizona on March 19, 1995. Codes ending in double digits are reserved as '''easily recognizable code'''s (ERCs), to be used for special purposes such as toll-free 800, 888, 877, 866 and 855, personal [[Area code 700|700]] numbers, and high-toll [[900 number]]s, rather than for geographic areas. (Nevada was denied '''777''' for this reason; it received [[area code 775|775]] instead when most of Nevada split from [[area code 702|702]], which continues to serve the [[Las Vegas metropolitan area]].) ===Splits and overlays=== By 1995, many cities in the [[United States]] and [[Canada]] had more than one area code, either through splitting the city into different areas (splits) or having more than one code for the same area (overlays). For example, in [[Manhattan]], subscribers' numbers had the NPA code 212, but two additional codes—first 917 (which initially was exclusively for cellular phones and pagers until that idea was struck down in a Federal court{{Citation needed|date=January 2012}}), then 646—were also introduced. This means that the area code must be dialed, even for local calls. In other areas, 10-digit or 11-digit dialing is now required for all local calls. The transition to 10-digit dialing typically starts with a permissive dialing phase in which both 7-digit and 10-digit dialing is optional. During this period, the transition is heavily publicized. After a period of several months, the mandatory dialing phase is introduced, in which 7-digit dialing no longer works. [[Atlanta]] was the first US city to have mandatory 10-digit dialing throughout its metropolitan area, roughly coinciding with the [[1996 Summer Olympics]] held there. Atlanta was used as the test case not only because of its size, but also because it enjoyed the world's largest fiber optic network at the time (five times that of [[New York City|New York]] then), and it was home to [[BellSouth]] (now part of AT&T), then the Southeastern [[Regional Bell Operating Company]].{{Citation needed|date=December 2009}} * 7-digit dialing: NXX xxxx (NPA code not required) * 10-digit dialing: NPA NXX xxxx * 11-digit dialing: 1 NPA NXX xxxx (1 is the NANP trunk prefix for long distance circuits). The overlap between area codes and exchange prefixes has occasionally produced some confusion because the three digits can be the same for both. [[Nashua, New Hampshire|Nashua]], New Hampshire, for example, has a local exchange code, (603) 888. 888 is also an area code for toll-free calls. If somebody in Nashua means to call 1-888-555-1212, but forgets the trunk prefix 1, he or she will actually dial the local number 603-888-5551. This, however, is generally not a problem in major [[metropolitan area]]s with overlapping area codes, which were mandated by the [[Federal Communications Commission|FCC]] to dial all ten digits for all local calls so as not to give new numbers or telecommunications providers a disadvantage. ===Expansion issues=== Depending on the techniques used for area code expansion, the effect on telephone users varies. In areas in which overlays were used, this generally avoids the need for converting telephone numbers, so existing directories, business records, letterheads, business cards, advertising, and "speed-dialing" settings can retain the same phone numbers, while the overlay is used for new number allocations. The primary impact on telephone users is the necessity of remembering and dialing 10- or 11-digit numbers when only 7-digit dialing was previously permissible. The use of a splitting instead of an overlay generally avoids the requirement for mandatory area-code dialing, but at the expense of having to convert some of the numbers to the new code. In addition to the requirements of updating records and directories to accommodate the new numbers, for efficient conversion this requires a period of "permissive dialing" in which the new and old codes are both allowed to work. Also, many splittings involved significant technical issues, especially when the area splittings occurred over boundaries other than phone network divisions. As an extreme example of an area code splitting gone somewhat awry, in 1998 [[area code 612]], which had covered the [[Minneapolis – Saint Paul]] Twin Cities, was split to create [[area code 651]] for [[Saint Paul, Minnesota|St. Paul]] and the eastern metropolitan area. The [[Minnesota Public Utilities Commission]] mandated that the new boundary exactly follow municipal boundaries (which were distinctly different from telephone exchange boundaries), and that all subscribers keep their 7-digit numbers. These two goals were directly at odds with the reason for the split (to generate additional phone numbers), and there were more than 40 exchanges whose territory straddled the new boundary. The result was prefixes duplicated in both area codes, which counteracted much of the benefit of the splitting, with only 200 of 700 prefixes in area 612 moving entirely to area 651. As a result, in less than two years area code 612 again exhausted its supply of phone numbers, and it underwent another three-way split in 2000, creating the new [[area code 763|area codes 763]] and [[area code 952|952]]. Again, the split followed political boundaries rather than rate center boundaries, resulting in additional split prefixes; a few numbers moved from 612 to 651 and then to 763 in less than two years. ===Decrease in expansion rate=== Recognizing that the proliferation of area codes was largely due to the telecom deregulation act and the assignment of numbers in blocks of 10,000, the FCC instructed NANPA (by then administered by [[Neustar]]) to look for a way to alleviate the numbering shortage. As a result a new program called "number pooling" was piloted in 2001, which allowed allocating numbers in blocks of 1,000 rather than 10,000. Because of the design of the switched telephone network, this was a considerable technical challenge and was carried out together with another technically challenging program, [[local number portability]]. Since then the program has been rolled out to most parts of the United States and, together with aggressive reclamation of unused number blocks from telecom providers, has reduced the need for additional area codes, so much so that many previously designated area splits and overlays have been postponed indefinitely. ===New area codes outside the U.S. and Canada=== Before 1995, all other NANP countries and territories outside the fifty United States and Canada, including [[Puerto Rico]] and the [[United States Virgin Islands|U.S. Virgin Islands]], shared the NPA code 809, but they can now have separate codes. Code [[Telephone numbers in the Dominican Republic|(809)]] is now only used by the [[Dominican Republic]]. In 1997 the United States Pacific Territories of the [[Northern Mariana Islands]] and [[Guam]] became part of the NANP, as did [[American Samoa]] in October 2004. The Dutch possession of [[Sint Maarten]] was originally scheduled to join the NANP on May 31, 2010, but the changeover was postponed to September 30, 2011.<ref name="Sint Maarten delay"/> '''Bermuda''': * Until 1995: '''+1 809 29'''x xxxx * After 1995: '''+1 441''' xxx xxxx '''Puerto Rico''': * Until 1996: '''+1 809 xx'''x xxxx * 1996-2001: '''+1 787''' xxx xxxx * After 2001: '''+1 787''' xxx xxxx ''or'' '''+1 939''' xxx xxxx (overlay for entire island) '''US Virgin Islands''': * Until 1997: '''+1 809 xx'''x xxxx * After 1997: '''+1 340''' xxx xxxx '''Northern Marianas''': * Until 1997: '''+670''' xxx xxxx * After 1997: '''+1 670''' xxx xxxx '''Guam''': * Until 1997: '''+671''' xxx xxxx * After 1997: '''+1 671''' xxx xxxx '''American Samoa''': * Until October 1, 2004: '''+684''' xxx xxxx * After October 2, 2004: '''+1 684''' xxx xxxx '''Sint Maarten''': * Until September 30, 2011: '''+599 5'''xx xxxx * From September 30, 2011: '''+1 721''' xxx xxxx ===Number size expansion=== {{Main|North American Numbering Plan expansion}} Likely sometime after 2038, the NANP system may face the task of adding one or two digits to each number.<ref>[http://www.nanpa.com/pdf/NRUF/April_2008_NANP_Exhaust_Analysis.pdf April 2008 NANP Exhaust Analysis]</ref> During that time, all public and private phone systems within the NANP area will have to be upgraded and reprogrammed (or even replaced) to recognize the new dialing rules. One plan being considered adds a 1 or 0 either to the beginning or end of the [[area code]] or the beginning of the 7-digit subscriber number, which will require mandatory 11-digit dialing even for local calls, between any two NANP numbers, well before the transition period. In another proposal, existing codes would be changed to "x9xx" (e.g. [[San Francisco]]'s 415 would become '''4915'''); once that conversion is complete, the new second digit would be opened for a new range. (Compare [[Telephone numbers in the United Kingdom#PhONEday|PhONE Day]] in the [[United Kingdom]], which added a "1" to the beginning of area codes in preparation for later using other digits, such as "2", for new area codes.) Other proposals include reallocating blocks of numbers assigned to smaller long distance carriers or unused reserved services. NANPA previously coordinated an expansion of [[Interexchange carrier|long-distance carrier]] access ("dial-around") codes from five digits (such as 10-321) to seven (10-10-321), in 1998. [[Vertical service code]]s, such as *69 ([[Callback (telecommunications)|callback]]) and *70 (suspend [[call waiting]]), have been designed to allow the use of both two- and three-digit codes. =={{anchor|List of NANPA countries and territories}} NANP countries and territories== *{{Flag|American Samoa}} - '''[[Area code 684|+1 684]]''' *{{Flag|Anguilla}} - '''[[Area code 264|+1 264]]''' *{{Flag|Antigua and Barbuda}} - '''[[Area code 268|+1 268]]''' *{{Flag|Bahamas}} - '''[[Area code 242|+1 242]]''' *{{Flag|Barbados}} - '''[[Area code 246|+1 246]]''' *{{Flag|Bermuda}} - '''[[Area code 441|+1 441]]''' *{{Flag|British Virgin Islands}} - '''[[Area code 284|+1 284]]''' *{{Flag|Canada}} - '''[[Area code 514|+1 514]]''', '''[[Area code 613|+1 613]]''', etc. *{{Flag|Cayman Islands}} - '''[[Area code 345|+1 345]]''' *{{Flag|Dominica}} - '''[[Area code 767|+1 767]]''' *{{Flag|Dominican Republic}} - '''[[Telephone numbers in the Dominican Republic|+1 809]]''', '''[[Telephone numbers in the Dominican Republic|+1 829]]''', '''[[Telephone numbers in the Dominican Republic|+1 849]]''' *{{Flag|Grenada}} - '''[[Area code 473|+1 473]]''' *{{Flag|Guam}} - '''[[Area code 671|+1 671]]''' *{{Flag|Jamaica}} - '''[[Area code 876|+1 876]]''' *{{Flag|Montserrat}} - '''[[Area code 664|+1 664]]''' *{{Flag|Northern Mariana Islands}} - '''[[Area code 670|+1 670]]''' *{{Flag|Puerto Rico}} - '''[[Telephone numbers in Puerto Rico|+1 787]]''', '''[[Telephone numbers in Puerto Rico|+1 939]]''' *{{Flag|Saint Kitts and Nevis}} - '''[[Area code 869|+1 869]]''' *{{Flag|Saint Lucia}} - '''[[Area code 758|+1 758]]''' *{{Flag|Saint Vincent and the Grenadines}} - '''[[Area code 784|+1 784]]''' *{{Flag|Sint Maarten}}<ref name="Sint Maarten delay">{{cite web|url=http://www.nanpa.com/pdf/PL_418.pdf |title=PL-418: Introduction of NPA 721 (Sint Maarten) |publisher=North American Numbering Plan Administration |date=2011-01-05 |accessdate=2011-08-08}} Updated by: {{cite web|url=http://www.nanpa.com/pdf/PL_423.pdf |title=PL-423: Updated Information - Introduction of NPA 721 (Sint Maarten) |publisher=North American Numbering Plan Administration |date=2011-07-27 |accessdate=2011-08-08}}</ref> - '''[[Area code 721|+1 721]]''' *{{Flag|Trinidad and Tobago}} - '''[[Area code 868|+1 868]]''' *{{Flag|Turks and Caicos Islands}} - '''[[Area code 649|+1 649]]''' *{{Flag|United States}} - '''[[Area code 212|+1 212]]''', '''[[Area code 213|+1 213]]''', '''[[Area code 312|+1 312]]''', etc. *{{Flag|United States Virgin Islands}} - '''[[Area code 340|+1 340]]''' ==Toll charges== Despite the similar dialing format, calls between different countries and territories that use the NANP are not charged as domestic calls. Calls between the US and Canada are treated as international, excluding them from some flat-rate long-distance plans, but are typically charged at lower rates than calls to other countries.<!-- A few local exceptions: [[Fort Covington, New York]]-[[St. Regis, Quebec]] and [[Derby Line, Vermont]]-[[Rock Island, Quebec]] are local calls, [[Hyder, Alaska]] and [[Estcourt Station, Maine]] are actually on Canadian numbers. These are extremely small villages divided by the border. --> Call costs to other destinations in the NANP area can be high; for example, it generally costs more to call [[Bermuda]] from the US than it does to call the UK or Japan, even though the dialing format is the same as the domestic format. Similarly, calls from Bermuda to US numbers, (including [[toll-free]] 1-[[Toll-free telephone number|800]]), incur high international rates. This was because many of the island nations at the time implemented a plan of subsidizing the cost of local phone services by directly charging heavier pricing levies on international Long Distance services. Because of these higher fees, [[scam]]s had taken advantage of customers' unfamiliarity with pricing structure to call the legacy regional area code 809. Some scams lured customers from the U.S. and Canada into placing expensive calls to the [[Caribbean]], by representing area code [[Telephone numbers in the Dominican Republic|809]] as a regular domestic, low-cost, or toll-free call. The split of 809 (which formerly covered all of the Caribbean NANP points) into multiple new area codes created many new, unfamiliar prefixes which could be mistaken for US or Canada domestic area codes but carried high tariffs. In various island nations, premium exchanges such as +1-876-HOT-, +1-876-WET- or +1-876-SEX- (where 876 is [[Jamaica]]) became a means to circumvent consumer-protection laws governing [[area code 900]] or similar US-domestic premium numbers. These scams are currently on the decline, with many of the [[Cable & Wireless (Caribbean)|Cable and Wireless]] service monopolies being opened up to competition, hence bringing rates down. Additionally, many Caribbean territories have implemented local government agencies to regulate telecommunications rates of providers.<ref>[http://www.ftc.gov.bb/index.php?option=com_content&task=view&id=18&Itemid=45 The Barbados Fair Trading Commission]</ref><ref>[http://www.ectel.int/telecoms-regulations.html The Eastern Caribbean Telecommunications Authority (ECTEL) > Telecom regulations]</ref> ==Dial plans== The [[dial plan]]s implemented by local telephone operating companies vary depending on whether an area has overlays, which are multiple NPA codes serving the same area, and whether the jurisdiction requires toll alerting, expressed by a leading 1 for regional toll calls. The NANPA publishes dial plan information in its information for individual area codes.<ref>[http://www.nanpa.com/nas/public/npa_query_step1.do?method=resetNpaReportModel NANPA information on individual area codes]</ref> The standard dialing plans in most cases are as follows: {| class=wikitable ! ! Local within area code ! Local outside area code ! Toll within area code ! Toll outside area code |- |Single code area, with toll alerting |7D |7D or 10D |1+10D |1+10D |- |Single code area, without toll alerting |7D |1+10D |7D or 1+10D |1+10D |- |Overlaid area, with toll alerting |10D |10D |1+10D |1+10D |- |Overlaid area, without toll alerting |10D or 1+10D |1+10D |10D or 1+10D |1+10D |} Most areas allow permissive dialing of 10D or 1+10D even for calls that could be dialed as 7D. The number of digits dialed is unrelated to whether a call is local or toll when there is no toll alerting. Allowing 7D local dialing across an area code boundary (which is uncommon today and only possible with toll alerting) requires NXX protection on the other side to avoid dialing conflicts. Most areas permit local calls to be dialed as 1+10D except for Texas, Georgia, and some jurisdictions in Canada which require that landline callers know which numbers are local and which are toll, dialing 10D for all local calls and 1+10D for all toll calls. In almost all cases, operator-assisted calls require dialing 0+10D. ===Special numbers and codes=== Some common special numbers in the North American system: * 0 - [[Operator assistance]] * 00 - [[Long-distance operator]] assistance * [[011]] - International Access Code. (For all destinations outside the NANP) * 01 - International Access Code using operator assistance. (For all destinations outside the NANP) * 10x xxxx - Used to select use of an alternative [[Interexchange carrier|long-distance carrier]] * [[2-1-1|211]] - Community information or social services (In some cities), formerly payphone refund line (and prior to that, used to access "long distance" operators or as a [[ringback number]] in some cities) * [[3-1-1|311]] - City government or non-emergency police matters such as noise complaints, suspicious people, minor injuries and non-working streetlights and parking meters, etc. (In some cities) * 4101 - On some older (obsolete) mechanical telephone systems, dialling 4101 and hanging up would [[ringback number|ring back]] the calling line. This was a means to ring the other user of the same [[party line (telephony)|two-party line]]. Deprecated (along with 4104 for repair services) to avoid confusion with [[area code 410]] or to allow use of 410-xxxx as a standard NXX [[local exchange]]. * [[4-1-1|411]] - Local telephone directory service (Some telephone companies provide national directory assistance) * [[5-1-1|511]] - Traffic, road, and tourist information or [[Automatic number announcement circuit|reads back]] the number being calling from * [[6-1-1|611]] - Telephone line repair service (Some telephone companies use this instead of 4104 or 811). Also used by mobile telephone companies to reach customer service * [[7-1-1|711]] - Relay service for customers with hearing or speech disabilities. Formerly used for single-announcement time and temperature in many areas. * [[8-1-1|811]] - "Dig safe" underground pipe safety line in the United States, mainly to encourage people not to hit telephone or power lines when they dig. Non-urgent [[telehealth]] services in Canada (formerly telephone company business office) * [[9-1-1|911]] - [[emergency telephone number|Emergency dispatcher]] for fire department, ambulance, police etc. * 958-xxxx - [[automatic number announcement circuit|Returns the number on the line]] via a recorded voice (in some areas). It was once common to reserve an entire unused exchange prefix (such as 830 or 958 or 9580 or 998) or an X-1-1 number for this purpose. These have largely moved to individual unpublished numbers within the standard 958-xxxx (local) or 959-xxxx (long-distance) plant test exchanges. * (Area Code) + 555-1212 - Non-local directory service There are also [[Vertical service code|special codes]], such as: * '''*51''' and '''1151''' A history of unanswered calls on a telephone number, useful for those who are not [[Caller ID]] subscribers. * '''*57''' and '''1157''' Used to "[[Call tracing|trace]]" harassing, threatening, abusive, obscene, etc. phone calls, and keep results of trace at phone company. * '''*66''' and '''1166''' To keep retrying a busy-line (see also [[Called-party camp-on]]) * '''*67''' and '''1167''' Caller ID Block * '''*69''' and '''1169''' Call Return ''caller may press '1' to return call after hearing number'' * '''*70''' and '''1170''' Cancel call waiting on a call-by-call basis * '''*71''' and '''1171''' Three way calling, which lets a person talk to people in two different locations at the same time. * '''*74''' and '''1174''' Speed dialing, which allows someone to quickly dial any of eight frequently called numbers using a one-digit code, from any phone on their line. *75 allows a total of 30 speed-call numbers. * '''*82''' and '''1182''' ''Releases Caller ID block on a call-by-call basis'' '''Note''': The four digit numbers do not work in some areas. The codes prefixed with the "*" symbol are intended for use on [[Touch-Tone]] [[telephone]]s, whereas the four-digit numbers prefixed 11xx are intended for use on older [[rotary dial telephone]]s, where the [[Touch-Tone]] '''*''' symbol is not available. Not all NANPA countries use the same codes. For example, the [[emergency telephone number]] is not always 911: [[Trinidad and Tobago]] and [[Dominica]] uses [[999 (emergency telephone number)|999]], as in the [[United Kingdom]]. The country of [[Barbados]] uses 211 for [[police|police force]], 311 for [[fire station|fire]], and 511 for [[ambulance]], while [[Jamaica]] uses 114 for directory assistance, 119 for [[police|police force]], and 110 for [[fire station|fire]] and [[ambulance]] services. Despite its early importance as a share of the worldwide telephone system, few of the NANP's codes, such as 911, have been adopted outside the system. Determining that 911 requires unnecessary rotation time on rotary dial telephones, the [[European Union]] has adopted its own standardized number of [[1-1-2|112]], while countries in Asia and the rest of the world use a variety of other two- or three-digit [[emergency telephone number]] combinations. The 112 code is gaining prevalence because of its preprogrammed presence in mobile telephones that conform to the European [[GSM]] standard. The European Union and many other countries have chosen the [[International Telecommunication Union]]'s '''00''' as their international access number instead of 011. The toll-free prefix '''800''' has been widely adopted elsewhere, including as the international toll-free country code. It is often preceded by a 0 rather than a 1 in many countries where 0 is the [[trunk prefix]]. ==Alphabetic mnemonic system== Telephone dials and usage in the NANP service areas maintain the tradition of alphabetic dialing. On most US and Canadian telephones, three letters appear on each number button from 2 through 9 (as standardized much later by [[ISO/IEC 9995|ISO 9995-8]] and, in Europe, [[E.161]]). This accommodates 24 letters. Historically, the letters Q and Z were omitted, though on some modern telephones they are added, so that the alphabet is apportioned as follows: 2 = ABC 3 = DEF 4 = GHI 5 = JKL 6 = MNO 7 = PRS or PQRS 8 = TUV 9 = WXY or WYZ or WXYZ No letters are typically mapped to the 1 or 0 keys, although some corporate [[voicemail]] systems use Q and Z as 1, and some old telephones assigned the Z to the digit 0. Originally, this scheme was used as a mnemonic device for telephone number prefixes. When telephone numbers in the US were standardized in the mid-20th century to seven digits, the first two digits of the exchange prefix were expressed as letters rather than numbers, using the name of the telephone exchange. Before [[World War II]], the large cities used three letters and four or five numbers; in most cities with customer dialing, phone numbers had only six digits (2L-4N). The prefix was a name, and the first two or three letters (usually shown in capitals) of the name were dialed. Later, the third letter (where previously used) was replaced by a number, or an extra number was added; this generally happened after World War II, although [[New York City]] did this in 1930. Thus, the famous [[Glenn Miller]] tune "[[PEnnsylvania 6-5000]]" refers to a telephone number +1 (212) 736-5000, the number of the [[Hotel Pennsylvania]], which still bears the same number today. Similarly, the classic film "[[BUtterfield 8]]" is set in the East Side of [[Manhattan]] between roughly 64th and 86th Streets, where the telephone prefixes include 288. This is why, in some works of fiction, phone numbers will begin with "KLondike 5" or "KLamath 5", which translates to [[555 (telephone number)|555]], an exchange that is reserved for information numbers in most areas. The letter system was phased out, beginning before 1965 (though it persisted ten years later in some places, and was included in [[Bell of Pennsylvania]] directories until 1983), but alphabetic dialing remains as a commercial [[mnemonic]] gimmick, particularly for toll-free numbers. For example, one can dial [[1-800-Flowers|1-800-FLOWERS]] to send flowers to someone, or 1-800-DENTIST to find a local dentist. Sometimes, longer [[phoneword]]s are used&nbsp;— for example one might be invited to give money to a public radio station by dialing 1-866-KPBS-GIVE. The "number" is 8 digits long, but only the first seven need be dialed. If an eighth (or more) digit is dialed, the switching system will ignore it. Mobile and [[voice over IP|VoIP]] users may need to manually drop any numbers past the seventh digit as some mobile switching systems will not automatically ignore them, resulting in a failed call. Also, some users of [[smartphone]]s can have difficulty dialing phonewords, as some of those devices do not have the apportioned letters on the keys used for dialing. This can be avoided by accompanying the use of phonewords with the actual numeric phone number, allowing users of such smartphones to dial using the numeric phone number. Some smartphones permit dialing phonewords by holding down a special function key, such as ALT in the case of the [[BlackBerry]], while pressing another key on the qwerty pad. In addition to commercial uses, alphabetic dialing has occasionally influenced the choice of regional area codes in the United States. For example, when [[area code 423|area 423]] ([[East Tennessee]]) was split in 1999, the region surrounding [[Knoxville, Tennessee|Knoxville]] was assigned [[area code 865]], chosen to represent the word "VOL"—short for "Volunteers", the nickname of athletic teams at the [[University of Tennessee]].<ref>See Brewer, Bill. "[http://www.areacode-info.com/headline/1999/tn990417.htm 423 Area Code To Become VOL In 9 ET Counties]." ''Knoxville News-Sentinel''. April 17, 1999.</ref><ref>[http://www.state.tn.us/tra/pressr/1999/vol865.pdf Tennessee Regulatory Authority press release], April 29, 1999</ref> The state of Nevada has previously attempted to obtain area code 777 (lucky 7's), but was unable to secure it.<ref>{{cite news | authorlink = Associated Press | author = Associated Press | title = State approves plan for second area code in northern Nevada | url = http://areacode-info.com/!headline/1998/nv980206a.htm | work = Las Vegas SUN | publisher = [[Greenspun Media Group]] | date = 1998-02-06 | accessdate = 2007-12-01 | quote = Doug Hescox, area code administrator for Nevada and California, hasn't divulged options for the new code. But he said a "lucky" 777 or a code close to the old 702 - like 701 or 703 - are already reserved or in use elsewhere. }}</ref> ==Cellular services== A difference between the NANP system and other plans is that, apart from an obscure, rarely-used [[area code 600]] in Canada, no separate, non-geographical area codes have been created for [[cellular phones]], as is the case in most European and Asian countries, where mobile services are assigned their own prefixes. This means that most North American mobile phones are assigned the same locality-specific codes as landlines, and calls to them are billed at the same rate. Consequently, the "caller pays" pricing model adopted in other countries, in which calls to cellular phones are charged at a higher nationwide rate but incoming mobile calls are not charged to the mobile user, could not be used. Instead, North American cellular telephone users are also generally charged to receive calls as well ("subscriber pays"). In the past, this discouraged mobile users from using the phones or giving out the number. However, robust price competition among carriers has led to dramatic cuts in the average price per minute for contract customers (for both inbound and outbound calls), which can compare favorably to those in caller-pays countries. Most users select bundle pricing plans that include all the minutes they expect to use in a month. Of the four major national carriers in the U.S., three ([[AT&T Mobility|AT&T]], [[Sprint Nextel|Sprint]], and [[T-Mobile USA|T-Mobile]]) offer free calling between mobile phones on the carrier's network, and Sprint also offers its customers free calling to mobile phones on other networks. Some industry observers have blamed "subscriber pays" as one of the main factors in the relatively low [[mobile phone penetration rate]] in the United States compared to that of Europe. In this model the convenience of the mobility is charged to the subscriber. Callers from outside the local-calling region of the assigned number, however, pay for a long-distance call, although domestic long distance rates are generally lower than the rates in caller-pays systems. Conversely, an advantage of caller-pays is the relative absence of [[telemarketing]] and [[nuisance call]]s to mobile numbers. The integrated numbering plan also enables [[local number portability]] between fixed and wireless services within a region, allowing users to switch to mobile service while keeping their phone number. The initial plan for overlays did allow for providing separate area codes for use by mobile phones, faxes, pagers, etc., although these were still assigned to a specific geographical area, rather than the nationwide mobile area codes common to most other countries, and were charged at the same rate as other area codes. Initially, the new area code 917 for [[New York City]] was specifically assigned for this purpose within the 5 boroughs; however, a Federal court struck this down and banned the use of an area code for a specific telephony purpose.{{Citation needed|date=August 2009}} Since mobile telephony is expanding faster than landline, new area codes typically have a disproportionately large fraction of mobile numbers, although landline and other services rapidly follow and local network portability can blur these distinctions. The experience of [[Hurricane Katrina]] and similar events revealed a possible disadvantage of the methods employed in the geographic assignment of cellular numbers. Many mobile phone users could not be reached, their phones rendered inoperable, even when they were far from the stricken areas, because the routing of calls to their phones depended on equipment in the affected area. Another related issue for services like mobile telephony is the scarcity of telephone numbers. In contrast to other countries, where mobile and other special-number operators enjoy wide leeway to generate large quantities of telephone numbers, this is not an option in the NANP, with its geographical area codes with a fixed number of digits. ==Fictional telephone numbers== {{Main|555 (telephone number)}} In [[United States|American]] [[television show]]s and [[film]]s, 555, and in older movies and shows, KLondike 5 or KLamath 5, is used for the exchange prefix of fictional [[telephone number]]s, so if anyone is tempted to telephone a number seen on screen, it does not cause a nuisance to any actual person. There are occasions, however, when a realistic telephone number is used in real-life context (often in songs), with varying intents and consequences. A classic example is the [[1982 in music|1982]] song "[[867-5309/Jenny]]" by [[Tommy Tutone]], which is still the cause of a large number of nuisance calls, although an Indianapolis plumbing company used both the tune and the number for advertising purposes. Similarly, not all numbers beginning with "555" are fictional. For example, [[555-1212]] is the number for [[directory assistance]] in many places. In many,{{which|date=March 2013}} but not all areas,{{which|date=March 2013}} dialing "555" numbers other than 555-1212 will route the caller to directory assistance. Only 555-0100 through 555-0199 are now reserved for fictional use, with the other numbers having been released for assignment. Where used, these are normally information numbers; [[Bell Canada]] and [[BCTel]] had briefly promoted 555-1313 as a pay-per-use "name that number" reverse lookup in the mid-1990s.<ref>{{cite news|title=Canadian telco offers users a handy reverse directory.|publisher=America's Network|date=May 15, 1996}}</ref> Since "1xx" exchanges are generally not assigned, some movies have started to use fictional telephone numbers starting with "1". There are various numbers which are deliberately not issued (for instance, numbers like +1-212-718-xxxx, where 212 and 718 are both existing or proposed New York City area codes, are typically avoided to prevent confusion between an area code and a similarly-numbered local exchange in the same region). 958-xxxx and 959-xxxx are very commonly reserved for plant test (local and long distance, respectively); a few area codes once reserved additional test exchanges such as 999-xxxx, although this usage is declining. Area codes where the last two digits match are reserved for non-geographic numbers such as +1-800 or +1-888; if there is little or nothing in [[area code 500]], there is no immediate probability of new non-geographic prefixes in the same range (such as +1-555) being created. A 0 or 1 in the first digit of an area code or seven-digit local number is invalid, as is a 9 as the middle digit of an area code. Lists of exchanges in an individual area code (posted by CNAC in Canada, NANP in the US) all list various specific reserved prefixes as deliberately not issued. Unlike the 555 exchange, many of these see little or no use as fictional telephone numbers. ==See also== *[[List of area code overlays]] *[[List of country calling codes]] *[[List of North American Numbering Plan area codes]] *[[List of original NANPA area codes]] *[[North American Numbering Plan expansion]] *[[Area codes in the Caribbean]] *[[Vertical service code]] ==References== {{Reflist|2}} ==External links== *[http://www.nanpa.com North American Numbering Plan Administration (NANPA)] :*[http://www.cnac.ca/ Canadian Numbering Administrator] :*[http://www.ectel.int/Regulatory%20Framework/July25thNumberingPlanVersion15.pdf Caribbean numbering plan for several islands in the NANP] *[http://www.lincmad.com/map1947.html Map of the original 86 area codes from 1947] *[http://www.radicalcartography.net/?areacode Animation of US area codes since 1947] *[http://www.nanc-chair.org/ North American Numbering Council] *[http://www.porticus.org/bell/doc/NANP_Discussion_2003R3.doc NANP Discussion 2003 Document - "Understanding the North American Numbering Plan"] {{Telecommunications}} {{Americas topic|Telephone numbers in}} {{Area code list}} {{Continent topic |name = Telephone numbers by continent |title = Telephone numbers by continent |prefix = Telephone numbers in_ }} [[Category:North American Numbering Plan|*]] [[Category:Telephone numbers]]'