National Conventions For Writing Telephone Numbers - What Is My International Phone Number

The national conventions for writing telephone numbers vary by country. International standards exist in the form of the International Telecommunication Union sector ITU-T issued recommendation E.123. Written conventions are closely related to the telephone numbering plan in use, which defines the length of numbers and assigns them meaning.

The presentation of telephone numbers in this article is intended for dialing within each country, and does not include any international dialing codes. In examples, a numeric digit is used only if the digit is the same in every number, and letters to illustrate groups. X is used as a wildcard to represent any digit in lists of numbers.

North America

Because the countries of World Numbering Zone 1 (North America) have the country code 1, the same number as is used for the trunk prefix, it is advisable to use international format of writing: Example: Within N. Amer. zone (302)1234567 Telephone International +1302 1234567

United States, Canada, and other NANP countries

Twenty-four countries and territories share the North American Numbering Plan (NANP), with a single country code. It is a closed telephone numbering plan in which all telephone numbers consist of 10 digits, with the first three digits representing the area code. Multiple area codes may be overlaid in the same region.

Several different types of formats are common in the United States:

• The traditional formatting convention for phone numbers is (NPA) NXX-XXXX, where NPA is the area code and NXX-XXXX is the subscriber number. The NXX prefix of the subscriber number indicates the local telephone exchange or rate center.
• The format can be written NPA-NXX-XXXX, or as 1-NPA-NXX-XXXX when including the number 1, the long-distance trunk access code.
• Sometimes the stylized format NPA.NXX.XXXX is seen, more common since the rise of the Internet and the dot-separated notation of domain names.

Originally, local calls within an area code could be placed by dialing NXX-XXXX (omitting the area code), known as 7-digit dialing. The traditional formatting convention included the area code in parenthesis to indicate that dialing the area code for local calls was optional. Calling a number in a different area code required dialing that code first (i.e., NPA-NXX-XXXX) known as 10-digit dialing. Most codes retain these rules today; in these areas, phone numbers continue to be written as 7-digit numbers, and frequently appear on signage for local stores.

With the rapid growth of telephony in the late 20th century, large metropolitan areas saw the introduction of overlay codes in the mid and late 1990s. With two or more area codes becoming available in the same vicinity, mandatory ten-digit dialing rules were instituted, requiring the area code to be dialed for all calls. The trunk code 1 remains optional for local calls in some of these areas.

Atlanta area

In metro Atlanta, for example, it is common to see people write shorthand 4, 6, or 7, followed by ")" (end parenthesis) or "-" (hyphen), or sometimes "/" (forward slash) or just a space, instead of the full 404 (the city), 770 (the suburbs since 1995), or 678 (overlaid on both in 1998). This however is complicated by the Georgia Public Service Commission's choice of 470 for the next overlay code.

Canada

The Canadian Government has stated on its Language Portal of Canada that numbers are to be written with a hyphen between each sequence, as follows: 1-NPA-NXX-XXXX or NPA-NXX-XXXX. 10-digit dialing is now required throughout most of Canada, including all of British Columbia, Alberta, Saskatchewan, Manitoba, Quebec, Nova Scotia, and Prince Edward Island, as well as most of Ontario. Areas not yet requiring 10-digit dialing are Ontario's 807 area code, Newfoundland, New Brunswick, the Yukon, Northwest Territories, and Nunavut, although 10-digit dialing may be accepted in some of these areas.

Quebec

In the province of Quebec, where French is the first language, the Office québécois de la langue française has established that phone numbers must be written with spaces first and then a hyphen for the last sequence, as follows: 1 NPA NXX-XXXX. Educational institutions of Quebec will mark improperly written phone numbers as orthographical mistakes in academic texts.

Mexico

Mexico is not part of the North American numbering scheme.

Fixed lines are usually written for local audiences as XXX XX XX and XXXX XXXX, depending on the length, with or without dashes between the segments.

If a city code is indicated, it is by itself in parentheses or after (01), the long distance prefix for domestic calls, e.g. for a fixed line in Greater Mexico City:

• (01) 55 1234 5678
• (01 55) 1234 5678
• (55) 1234 5678

Mobile numbers always include the city code and are written either

• XXXXXXXXXX

or with spaces,

• XX XXXX XXXX for cellphones from Greater Mexico City, Guadalajara and Monterrey
• XXX XXX XXXX for those based elsewhere.

Sometimes (044) is placed in front, which is the prefix required to dial a cellphone from a landline based in the same city.

Thus, a Tijuana-based cellphone may be written:

• 6641234567
• 664 123 4567
• 664 123 45 67
• (044) 664 123 4567
• (044) 664 123 45 67

On billboards it is common to see a Mexico City cellphone number as the contact to place an ad there, and (045) is placed before the number which is the prefix dialed from a non-Mexico City landline to a Mexico City cellphone, e.g.

• (045) 55 1234 5678

International Phone Number Format

Europe

Belgium

Belgian telephone numbers consist of two major parts: Firstly '0', secondly the "zone prefix" (A) which is 1 or 2 digits long for landlines and 3 digits long for mobile phones and thirdly the "subscriber's number" (B).

Land lines are always 9 digits long. They are prefixed by a zero, followed by the zone prefix. Depending on the length of the zone prefix, the subscriber's number consists of either 6 or 7 digits. Hence land line numbers are written either 0AA BB BB BB or 0A BBB BB BB.

Mobile Phone numbers always consist of 10 digits. The first digit of the "zone prefix" of a mobile number is always '4'. Then follows 2 digits indicating to which Mobile Operator's pool the number originally belonged when it was taken into usage. The fourth digit represents a "sub-group" of this pool and has no additional meaning other than increasing the amount of possible numbers. The subscriber's number consists of 6 digits. Hence, mobile phone numbers are written 04AA BB BB BB. Sometimes, the last 6 digits are written in two groups of 3 digits to increase readability: 04AA BBB BBB.

Numbers are sometimes written with a slash in between the zone prefix and the subscriber's number. This is the case for both land lines and mobile phone numbers. Sometimes, dots are written between the blocks of the subscriber's number. Examples: 0AA/BB BB BB, 0AA/BB.BB.BB; for mobile numbers: 04AA/BB BB BB, 04AA/BB.BB.BB or 04AA/BBB.BBB.

The international country code prefix for Belgium is "+32". When dialing a number with the prefix, the 0 can be dropped, e.g.: +32 4AA BB BB BB.

Denmark

Danish telephone numbers are eight digits long and are normally written

• in four groups of two digits each, with the groups separated by spaces: AA AA AA AA,
• in two groups of four digits each, with the groups separated by a space: AAAA AAAA,
• in one group of two digits followed by two groups of three digits each, with the groups separated by spaces: AA AAA AAA, or
• all in one go: AAAAAAAA.

Danish emergency and service numbers are three digits long and are written AAA. Danish short numbers used for text messaging services are four digits long and are written AAAA.

France

French telephone numbers are 10 digits long written in groups of two separated by spaces, in the format 0A BB BB BB BB where 0 (the trunk prefix) was created in 1996 to be a carrier selection code, and A is the "territorial area code" included in the subscriber number A BB BB BB BB.

The A (territorial area code) can be 1 to 5 (for geographic numbers, depending of the area in the country, respectively: Paris/Suburbs, N-W, N-E, S-E, S-W), and it designates nationwide numbers when it is 6 or 7 (mobile numbers), 8 (special numbers), or 9 (phone over IP over xDSL/non-geographic numbers).
The numbering plan is a closed one, all digits must always be dialed.
The first two or three B can designate the area (old area code) for geographic numbers, or the operator to whom the number resource belongs.

There are also "short numbers" for emergencies (such as 112), that are written 1C or 1CC; and short numbers for special services, written 10 CC, 11C CCC, or 36 CC. 00 is the international access code.

International format is +33 A BB BB BB BB where the leading trunk prefix 0 disappears (it must not be dialed from abroad). This format can be directly used in mobile phones.

Germany

German telephone numbers have no fixed length for area code and subscriber number.

There are many ways to format a telephone number in Germany. The most prominent is DIN 5008 (ISO 8601) but the international format E.123 and Microsoft's canonical address format are also very common.

Numbers are often written in blocks of two. Example: +49 (A AA) B BB BB (Note the blocks go from right to left)

The very old format and E.123 local form are often used by older people but also for technical reasons.

Hungary

In Hungary the standard lengths for area codes is two, except for Budapest (the capital), which has the area code 1. Subscribers' numbers are six digits long in general, numbers in Budapest and cell phone numbers are seven digits long.

Iceland

Phone numbers in Iceland are seven digits long and generally written in the form XXX XXXX or XXX-XXXX.

Italy

See Telephone numbers in Italy

Netherlands

Since 10 October 1995 (Operation Decibel) all telephone numbers in the Netherlands are 10 digits long (including the trunk prefix '0'). The area code ('A') is commonly separated with a dash ('-') and sometimes a space from the subscriber's number ('B'). Alternatively, the area code (including the trunk prefix) can be enclosed in parentheses.

The length of the area code for landlines is either 2 or 3 digits, depending on the population density of the area. This leaves 7 or 6 digits for the subscriber's number, resulting in a format of either 0AA-BBBBBBB or 0AAA-BBBBBB. Cellphone numbers are assigned the 1-digit area code 6, leaving 8 digits for the subscriber's number: 06-CBBBBBBB, where subscriber's number ('C') is neither 6 nor 7. Service numbers (area codes 800, 900, 906 and 909) have either 4 or 7 remaining digits, making them 8 or 11 digits in total: 0AAA-BBBB or 0AAA-BBBBBBB. The area code 14 has no trunk prefix and is used for government numbers, currently only for municipalities. The remaining digits represent the area code of the municipality. Therefore the length 14 numbers total either 5 of 6 digits: 14 0AA or 14 0AAA

The trunk prefix '0' is dropped when prefixed by the country code: +31 AA BBBBBBBB, +31 6 CBBBBBBB, etcetera. Note that there is not a trunk prefix for the 14 series so the international number becomes +31 14 0AAA.

Norway

Norwegian telephone numbers are 8 digits long. A number to a fixed line is written in four groups of two separated by spaces, AA AA AA AA. Cellphone numbers are written in three groups, AAA AA AAA. This makes it easy to determine if the B-number is SMS capable. Mobile numbers start with 4 or 9.

Portugal

Telephone numbers in Portugal are 9 digits long. Landline numbers have an area code with two (Lisbon and Porto) or three figures (for the other areas in the country):

• 21 XX XX XXX (for Lisbon area)
• 22 XX XX XXX (for Porto area)
• 256 XXX XXX (for São João da Madeira area)
• 309 XXX XXX (non-geographic)

In terms of mobile numbers:

• 91 XX XX XXX (Vodafone)
• 92 XX XX XXX (TMN/MEO)
• 93 XX XX XXX (Optimus/Zon)
• 96 XX XX XXX (TMN/UZO/Phone-ix)

Poland

Telephone numbers in Poland are 9 digits long. For mobile phones, the preferred format is AAA-AAA-AAA. For landline phones, the preferred format is AA-BBB-BB-BB, where AA is area code. Occasionally, you can encounter numbers formatted as (AA) BBB-BB-BB. Omitting area code is not permitted, because nowadays it is always required.

Russia

Telephone numbers in Russia are 10 digits long. Trunk prefix is 8 (or 8 CC if using alternative operator, where CC is 21â€"23, 51â€"55), it is always separated from area code by space. Length of geographical area codes (A) is usually 3 to 5 digits, depending on population density of the area; length of non-geographical area codes is 3. The groups of numbers of the subscriber's number (B) are separated by dashes ('-'): BBB-BB-BB, BB-BB-BB, B-BB-BB. Thus, the correct way to write local number is, e.g., 8 AAAA BB-BB-BB or (8 AAAA) BB-BB-BB to indicate that area code dialing is optional. Area code dialing is mandatory in all non-geographical area codes and optional in most geographical area codes; however, there are exceptions. For example, since July 1, 2012 area code dialing is mandatory in Moscow (area codes 495, 498, 499), so the only proper way to write Moscow number is 8 AAA BBB-BB-BB. In current usage, it is very common to see numbers (incorrectly) written as 8 (AAA) BBB-BB-BB. This usage is wrong, as the parentheses are meant to indicate the part of number that may be omitted.

Spain

Spanish telephone numbers are nine digits long, starting with '9' or '8' for fixed lines (excluding '90x' and '80x') or with '6' or '7' for mobile phones.

The first group in fixed lines always identifies the dialed province. That group might be of 2 or 3 digits; for example, 91 and 81 are for Madrid while 925 and 825 are for Toledo. The second group is always of 3 digits as it formerly identified the telephone exchange (it now identifies the telephone area).

When the first group is 2 digits long (as in Madrid), the number is usually written in four groups of 2-3-2-2 digits (AB CCC DD DD)

When the first group is 3 digits long (as in Toledo), the number is usually written in 3 groups of 3 digits (ABB CCC DDD) but the form 3-2-2-2 (ABB CC CD DD) is not uncommon.

Mobile numbers are usually grouped by threes, ABB CCC CCC, but the form 3-2-2-2 is also seen.

Switzerland

Swiss telephone numbers are 10 digits long, and usually written 0AA BBB BB BB where 0AA is the "national destination code" and BBB BB BB is the subscriber number. Sometimes numbers are written +41 AA BBB BB BB to include Switzerland's country calling code. Certain nationwide destination codes, such as for toll-free or premium-rate telephone numbers, are written 0800 BBB BBB or 0900 BBB BBB. There are also "short numbers" for emergencies such as 112 that are written 1CC or 1CCC.

United Kingdom

Dialling codes (also known as "area codes") are typically surrounded by parentheses, indicating that they are optional for local callers, and are followed by the customer's telephone number. Parentheses are not normally used on non-geographic area codes and mobile phone numbers.

Codes with the form 02x are followed by 8-digit local numbers and should be written as (02x) AAAA AAAA. Area codes with the form 011x or 01x1 are used for many of the major population centers in the UK, are always followed by 7-digit local numbers and should be written as (01xx) AAA BBBB. Other area codes have the form 01xxx with 5 or 6 figure local numbers written as (01xxx) AAAAA or (01xxx) AAAAAA; or have the form 01xxxx with 4 or 5 figure local numbers written as (01xx xx) AAAA or (01xx xx) AAAAA.

Geographic numbers are also sometimes displayed in a format with a dash separating the code and number, this was formerly the recommended format for six major metropolitan areas in the UK, e.g. 01x1-AAA BBBB. They are sometimes also shown in a format with a space between the code and number, similar to the non-geographic format, e.g. 01x1 AAA BBBB.

Numbers for mobile phones and pagers are formatted as 07AAA BBBBBB and most other non-geographic numbers are 10 figures in length (excluding trunk digit '0') and formatted as 0AAA BBB BBBB. However, these numbers are sometimes written in other formats. 9 figure freephone numbers are 0500 AAAAAA and 0800 AAAAAA and there are two numbers of 7 figures length: 0800 1111 (Childline) and 0845 4647 (NHS Direct).

Domestically, there are also a number of special service numbers such as 100 for the operator, 123 for the speaking clock and 155 for the international operator, as well as 118 AAA for various directory enquiry services, and 116 AAA for various helplines. For some services, the number you call will depend on which operator you use to connect the call. 111, 112 and 999 work for calling the emergency services. These numbers cannot be called from abroad.

When calling from abroad, the initial '0' trunk prefix is not required; it is, however, commonplace to represent telephone numbers with both the international code and the '0' trunk prefix - which is typically placed within parentheses - but this representation is inconsistent with the E.123 international standard.

Incorrect presentation of UK area codes and numbers

Misconceptions, particularly in the case of London numbers, mean that UK telephone numbers are frequently spoken and written incorrectly. A common error is treating London numbers as if there exist multiple area codes (e.g. "0207", "0208" and "0203". Similar tendencies are in evidence elsewhere, particularly in respect of 011x and 02x area codes changed between 1995 and 2000 by PhONEday and the Big Number Change.

Turkey

In Turkey the format for telephone numbers is commonly seen as 0BBB AAA AA AA. While landline numbers having the prefix 02BB AAA AA AA, 03BB AAA AA AA, or 04BB AAA AA AA mobile numbers have the prefix 05BB AAA AA AA. Landline area codes are separated by cities and only one city, Istanbul, has two area codes: 216 for the Asian side, and 212 for the European side. Mobile numbers however are separated by carriers. There are three mobile carriers in Turkey: Vodafone TR, Turkcell and AVEA. Turkcell has the prefix 053B AAA AA AA, Vodafone TR has the prefix 054B AAA AA AA, and AVEA has the prefix 055B AAA AA AA.

Since 9 November 2008, with the passing of the Number Carriability Regulation by ICTA, mobile numbers can be carried from one mobile carrier to the other, without having to change the prefix. This caused dialing 05BB to call another number on the same carrier to become mandatory. Calls to numbers which were carried to another operator are signaled by a unique sound upon dialing, to signify that the recipient is on another network and alert them against potentially unwanted interconnection charges. The same regulation passed on 10 September 2009 regarding landline numbers, without the requirement to dial the prefix among numbers with the same geographical area, sharing the same prefix.

The "0" on every prefix is an Area Code Exit code that must be dialed when a number with a different area code is being called. So when calling from outside of Turkey those 0s are not dialed. The dialing format when calling from outside Turkey is +90 BBB AAA AA AA and NOT +90 0BBB AAA AA AA. Unlike the North American system, the Country Exit Code isn't 011 but 00. So it is one "0" to exit area and one more "0" to exit the country.

Asia

Pakistan

Telephone numbers in Pakistan have two parts. Area codes in Pakistan are from two to five digits long; the smaller the city, the longer the prefix. All the large cities have two-digit codes.

Smaller towns have a six digit number. Large cities have seven-digit numbers. Azad Jammu and Kashmir has five digit numbers. On 1 July 2009, telephone numbers in Karachi and Lahore were changed from seven digits to eight digits. This was accomplished by adding the digit "9" to the beginning of any phone number that started with a "9" (government and semi-government connections), and adding the digit "3" to any phone numbers that did not start with the number "9".

It is common to write phone numbers as (0xx) yyyyyyy, where xx is the area code. The 0 prefix is for trunk (long-distance) dialing from within the country. International callers should dial +92 xx yyyyyyyy.

All mobile phone codes are four digits long and start with 03xx. All mobile numbers are seven digits long, and denote the mobile provider on a nationwide basis and not geographic location. Thus all Telenor numbers (for example) nationwide carry mobile code 0345 etc.

Universal access number

• 111 xxx xxx

Emergency Service Numbers

• 1xx
• 1xxx

Premium Rate services:

• 0900 xxxxx

Toll free numbers (For callers within Pakistan):

• 0800 xxxxx

India

Telephone numbers in India are 10 digits long (excluding an initial zero which is required at times) and fall in at least four distinct categories:

1. Landlines: Written as AAA-BBBBBBB, where AAA is the Subscriber Trunk Dialing code (long distance code) and BBBBBBB is the phone number. The total length of the Subscriber Trunk Dialing code and the phone number is 10 digits.
2. Mobiles: Written as AAAAA-BBBBB for ease of remembering (though the prefix is either 2-digits or 4-digits in the numbering plan). Mobile numbers which are not local need to be prefixed by a 0 while dialing, or by +91 (91 is the country code for India). A mobile number written as +91-AAA AAB BBBB is valid throughout India, and in other countries where the + is recognized as a prefix to the country code.
3. Toll Free: These are usually ten digit numbers beginning with 1-800. Sometimes they are accessible (or are toll-free) only when called from the government-owned telephone corporation, BSNL/MTNL.
4. Service numbers: These are usually three or four digit numbers (e.g. Police is 100) used to access an emergency service (Fire, Ambulance, Police, Roadside assistance) or a value-added service.

China

1. Landlines: In China, the length of phone numbers varies from city to city. It is usually written as (0XXX) YYYY YYYY（Some areas of the phone number in the format (0XXX) xxxx-xxx）, where 0 is the trunk code, XXX is the area code (2 or 3 digits) and YYYY YYYY is the local number (not necessarily 8 digits). For example, (0755) XXXX YYYY indicates a Shenzhen number. XXXXYYYY is dialed locally, 0755XXXXYYYY is dialed in other areas inside the country, while, for international calls to Shenzhen, the 0 is dropped and is written +86 755 XXXX YYYY.
2. Mobiles: The 11 digit code is always written in full in the whole China e.g. 1WX YYYY ZZZZ. Each WX is assigned to a service provider while W is usually '3', '5' or '8'. The remaining 8 digits are the subscriber number.

Hong Kong

Every number, except special service numbers, is an 8-digit number; they are grouped as XXXX YYYY. There are no area codes now.

Japan

The traditional convention for phone numbers is (0AA) NXX-XXXX, where 0AA is the area code and NXX-XXXX is the subscriber number. This number format is very similar to the North American numbering plan, however, the country has a trunk code of 0 instead of 1, so international callers (using +81) do not have to dial the trunk code when calling to Japan. Telephone numbers were nine digits long in Tokyo and Osaka until the late 1990s, when a seventh digit was added to the subscriber number. Densely populated areas have shorter area codes, while rural areas have longer area codes, however, the last two digits of a five digit long area code (including the first zero) may also be the first two digits of the subscriber number. Area codes increase from north to south, except in areas such as the western Hokuriku region and the prefecture of Okinawa, where area codes increase from west to east or south to north.

Some telephone numbers deviate from this rule:

• Toll-free dialing and Navi Dial operations (0120-XX-XXXX, 0570-XX-XXXX, or 0800-XX-XXXX), where XX-XXXX is the subscriber number
• The area code 050 uses an 11 digit phone number (050-XXXX-XXXX), where XXXX-XXXX is the subscriber number
• 110 and 119 are examples of three digit emergency numbers

Malaysia

All area codes including mobile start with a "0" (trunk prefix) for domestic calls. If you are dialing from another country the international calling code for Malaysia is "60" which may be confusing; do not dial an extra "0" before the rest of the digits. For fixed line and mobile phone numbers, a dash is written in between the area/mobile code and the subscriber number, with an optional space before the last four digits of the subscriber number. For example, a fixed line number in Kuala Lumpur is written as 03-XXXX YYYY or 03-XXXXYYYY, while a fixed line number in Kota Kinabalu is written as 088-XX YYYY or 088-XXYYYY. A typical mobile phone number is written as 01M-XXX YYYY or 01M-XXXYYYY. Toll-free and local charge numbers are written as 1-800-XX-YYYY and 1-300-XX-YYYY respectively, while premium rate numbers are written as 600-XX-YYYY.

Philippines

Telephone numbers in the Philippines are written as +63 (X) YYY ZZZZ or +63 (XX) YYY ZZZZ for international callers. For domestic calls, the country code (+63) is omitted and a trunk prefix (0) is placed. For local calls, both the 0 and area code are omitted. Mobile numbers are written as +63 (XXX) YYY ZZZZ or 0 (XXX) YYY ZZZZ.

Singapore

In Singapore, every phone number is written as +65-XXXX-YYYY or +65 XXXX YYYY.

Mobile phones starts with 8/9, landline phone numbers starts with 6 while VOIP numbers starts with 3.

Subscriber numbers have 8 digits and there are no area codes.

Taiwan

Landline numbers in Taiwan are written with the area code in parenthesis [with phone numbers totaling 9 digits] Example: (02) XXXX YYYY for phone numbers in Taipei area.

Mobile phones have 3 digit "company code" assigned to different mobile service carriers such as (09**) XXXXXX followed by a 6 digit phone number. (note: Mobile carriers could have multiple company codes)

South Korea

South Korean phone numbers can be as short as 7 digits and as long as 11 digits, because, when making a local call (i.e. in the same city), there is no need to dial the area code. South Korean area codes are assigned based on city.

Landline Phone Numbers

Landline home numbers are usually written as: 0XX-XXX-XXXX or 0XX) XXX-XXXX where 0XX indicates an area code. (0XX) XXX-XXX and 0XX XXX XXXX (without hyphens) are comprehensible as well. The area code may be two digits long for some cities such as Seoul and Gwacheon (interestingly, these two cities use the same area code) and three digits for other cities such as Incheon, Busan and most of the cities in Gyeonggi-do. The middle three-digit part is extended to four digits in many areas due to the increased number of telephone users.

In the international context, 82 0XX-XXX-XXXX is commonly used as well. For international calls, "0" in the area code is often omitted, because it is not necessary to dial 0 from foreign countries. Therefore, it is better written as: 82-(0)XX-XXX-XXXX or 82-(0)XX-XXXX-XXXX The plus (+) sign is often added to the country code too (e.g., +82 0XX-XXX-XXXX or +82-0XX-XXXX-XXXX).

Mobile Phone Numbers

For mobile numbers, 01X-XXX-XXXX is commonly used. With the third generations of the mobile phone, most of the mobile numbers start with 010 but there still are a number of people who continue to use the second generation, with the numbers starting with 011, 016, 017, so on. As with the landline home numbers, the mobile numbers' middle three-digit part is extended to four digits (e.g., 01X-XXXX-XXXX) due to the increased number of mobile phone users.

For mobile numbers in the international context, 82 (0)1X-XXX-XXXX or 82-(0)1X-XXXX-XXXX are most often used. As with the home phone numbers, the plus (+) sign is often added to the country code (e.g., +82 01X-XXX-XXXX or +82-01X-XXXX-XXXX)

Business Numbers

If an area code starts with 070, the number does not belong to any particular area, and is a number given by an Internet telephone service. In this case, 070 is not usually put in the brackets, neither ( ) nor ).

In the business context, the numbers in the format of 15XX-XXXX and 16XX-XXXX without any area code are business representative agency or customer services. While the numbers starting with 080 (e.g., 080-XXX-XXXX) are also business-related numbers but are usually toll-free customer service centers. Also in this case, 15XX, 16XX or 070 are not put in the brackets, neither ( ) nor ).

National Service Numbers

There are national telephone services which have phone numbers in the format of 1XX or 1XXX, without any area code. For example, 114 is for telephone yellow page, 119 is for fire/emergency number, 112 is for police station center, 131 is for weather forecast information, 1333 is for traffic information, and so on. One interesting number is 111 which is for reporting spies especially from North Korea. It used to be 113, so most of senior citizen still believe it is the number for reporting spies. These numbers do not need any brackets.

Alternative Numbers

If there are multiple numbers used for one person/entity, the symbol "~" is usually used to avoid repetitions. For example, if one company has three phone numbersâ€"031-111-1111, 031-111-1112 and 031-111-1113â€"then they are shortened as in 031-111-1111~3.

If the numbers are not consecutive, then the last digit is written together with commas. For example, if a company has three numbersâ€"031-111-1111, 031-111-1115, 031-111-1119, then they are shortened as in 031-111-1111, 5, 9.

Oceania

Australia

Australian telephone numbers are 10 digits long, and can be written 0A BBBB BBBB or 04MM MBB BBB (for mobile telephone numbers), where 0A is the optional "area code" and BBBB BBBB is the subscriber number. 04MM M are allocated per mobile network. When the number is to be seen by an international audience, it is written +61 A BBBB BBBB or +61 4MM MBB BBB. When written for a local audience, the optional area code is omitted. The area code is often written within parentheses (0A) BBBB BBBB.

Ten-digit non-geographic numbers beginning with 1 are written 1X0Y BBB BBB, where X is 8 for toll free numbers, 3 for fixed-fee numbers and 9 for premium services. Six digit non-geographic numbers are written 13 BB BB or 13B BBB; these are fixed-fee numbers. B's are sometimes written as letters. Occasionally, non-geographic numbers have more or fewer digits. These are written according to the third digit: if it is 0, the ten-digit pattern is used; otherwise, the six-digit pattern is.

New Zealand

Almost all New Zealand telephone numbers are seven digits long, with a single-digit access code and a single-digit area code for long-distance domestic calls. Traditionally, the number was given as (0A) BBB-BBBB, with the two first digits (the STD code) often omitted for local calls. The brackets and the dash are also often omitted. Mobile numbers follow the same format, but with the area code being two digits, i.e. (02M) BBB-BBBB. ( Some mobile numbers are longer: (021)02BBBBBB, (021)08BBBBBB, (020)40BBBBBB, (020) 41BBBBBB and (028) 25BBBBBB; and some are shorter: (021)3BBBBB, (021)4BBBBB, (021)5BBBBB, (021)6BBBBB, (021)7BBBBB, (021)8BBBBB and (021)9BBBBB)

There are also free-phone numbers (starting with 0800) that are given in the format 0800-AAA-AAA. It is not uncommon for the 0800 to be enclosed in brackets, although this is not strictly correct as the brackets denote optional parts of the number, and the 0800 is required.

For international use, the prefix +64 is substituted for the leading zero, giving +64-A-BBB-BBBB for land-lines, and +64-MM-BBB-BBBB for mobile numbers.

Central America

Some Central American countries write the country code for their own and other Central American countries in parentheses, instead of using a + sign, as recommended by E.123. For example, for a number in Costa Rica they would write (506) 2222-2222 instead of +506 2222-2222. On the other hand Guatemala does have the custom of using the + sign. It is quite common for Central American businesses to write the whole phone number, including the country code in parentheses, on business cards, signs, stationery, etc.

Costa Rica

Costa Rican telephone numbers are 8 digits long, and are usually written in the format 2NNN-NNNN (for landlines), 8NNN-NNNN (for mobile telephone numbers from local telephone company ICE), 6NNN-NNNN (for mobile telephone numbers from Movistar) and 7NNN-NNNN (for mobile phone numbers from Claro). Toll-free numbers use the format 800-NNN-NNNN and premium-rate telephone numbers are written 90x-NNN-NNNN where x varies according to the type of service offered. There are also "short numbers" for emergencies such as 911.

When Costa Rica switched from 7 to 8 digit numbers, it used a scheme similar to the 8 digit number scheme already in place in El Salvador at that time.

El Salvador

El Salvadoran telephone numbers are 8 digits long, usually written in the format 2NNN-NNNN (for landline use) and 7NNN-NNNN (for mobile telephone numbers). Premium-rate numbers start with a 9.

Guatemala

Guatemalan telephone numbers are 8 digits long and written in the format 2NNN-NNNN for landlines in Guatemala City, 6NNN-NNNN for landlines for the rest of municipalities in the Guatemala Department, and 7NNN-NNNN for landlines in Rural Guatemala / rest of country. Non-geographic numbers (mobile) are 5NNN-NNNN, 4NNN-NNNN, and 3NNN-NNNN. Within each area, there are different service providers. The following 3 digits indicate the service provider. However, their assignment is on a first-come first-served basis.

Additionally there are special numbers with the following conventions: 3 digit numbers for emergency systems, four digit numbers, 15NN for information and governmental institutions and 17NN for commercial and banking institutions with a high call influx, 6 digit numbers for Telephone carriers numbers and making operator assisted calls, collect calls. These calls are billed at different rates. 1-800: Toll-free calls redirected to out of country offices and 1-801: Local toll-free calls.

Honduras

Honduran telephone numbers have either 7 digits (for landlines), which are usually written NNN-NNNN, or 8 digits (for mobile numbers), which are written NNNN-NNNN. The fact that landline and mobile numbers are different lengths sometimes causes confusion.

In 2010, an additional digit (2) was added to the start of land line numbers, thus standardizing the length at 8 digits.

South America

Argentina

Argentinian telephone numbers always consist of 11 digits, including the geographical area code.

Area code

The area code can have 3, 4 or 5 digits, the first being always 0 (indicative of long distance calls). Moreover, in 1999 the whole country (except Buenos Aires, and Greater Buenos Aires) was divided into two zones. Roughly and with exceptions, one includes most of the northern half of the country; and the other, most of the southern half, though the actual reason for this division is not geographical, but the fact that each zone is administered by a different company.

So, the second digit of area codes can be 1 (only in Buenos Aires and Greater Buenos Aires code "011") or else a 2 (for towns in the southern half of the country) or a 3 (for the northern half). For example, (011) for Buenos Aires, (0341) for Rosario, (02627) for San Rafael. And the subscriber's number will accordingly have 6, 7 or 8 digits, to complete the eleven digits.

Phone numbers are mostly written as:

• (011) xxxx-xxxx (Note that only the (011) code has 3 digits),
• (0xxx) xxx-xxxx or
• (0xxxx) xx-xxxx

The area code is usually written between brackets.

Subscriber number

In 1999, a general reform was introduced to telephone numbers, including the 1, 2 and 3 for area codes as explained above, and adding a 4 at the beginning of all subscriber's numbers. However, since the reform some local numbers starting with a 5 are beginning to appear. Moreover, a hyphen is usually placed to separate the last four digits. Code areas do not usually include one single city or town, but several neighbouring towns. So, the part before the hyphen (called a prefix) is usually indicative of either a town within the code area, or even of a part of a larger city, which is assigned several prefixes. As a matter of fact, each area code has only a limited number of prefixes assigned, and these are locally limited within the area.

For example the (0342) area has numbers with a 456- prefix, mostly located in the centre of Santa Fe. It also has numbers with a 460- prefix, usually for phone lines in the north east of the city. And there are lines with a 474- prefix, located in Santo Tomé. But no 444- prefix exists within this area. As for the part after the hyphen, it may usually be any succession of four digits, though sometimes a prefix is shared by two or more small towns, and then, the first digit after the hyphen carries the distinction between towns.

Sometimes, a prefix is reserved for official numbers, that is for offices depending on the national, provincial or local state. In the (0342) area, this is 457-, and phones within this prefix communicate with each other, by simply dialing the four final digits, though from other phones the prefix must be dialled as well.

Mobile phones

Mobile phones use the same area codes as landline telephones, but the number begins with a "15", added to a string of 6, 7 or 8 digits, just as described above. After the "15", the remainder of the number can start with a 3, a 4, a 5 or a 6. This "15" may be dropped when a call is made to a mobile phone in a different code area. And when sending text messages, the receiver's number is best dialled both without the "15" and with the long distance code, even if both sender and receiver share a code area, but without the initial "0".

To sum up, given the mobile phone (011) 154-123-4567, you will call it by dialing:

• 154-123-4567 (within the same code area),
• (011) [15]4-123-4567 (from a different code area, including or omitting the 15),

And you will send messages to:

• 11 4-123-4567 (even when your phone has also a 011 number).

Special numbers

Two sorts of special numbers exist in Argentina. On the one hand, three-digit numbers are used for special services such as to call the police, fire brigade or emergency doctors, as well as to hear the official time. Also telephone companies have three-digit numbers to report a problem in the lines, or to ask for another subscriber's number, when a paper directory is not available.

Additionally, there are other longer numbers. These include (but are not limited to):

• 0800 xxx abcd
• 0810 xxx abcd
• 0600 xxx abcd

(where the xxx indicates the same digit dialled three times, and a, b, c and d may each be any of the ten digits)

0800 lines are used by companies, and it is the receiver and not the caller who pays for the call, so that potential clients are encouraged to contact business companies for free.

0810 lines are paid by the caller, but the cost is for a local call, even if you are calling from a different area. The remaining is covered by the receiver.

And 0600 numbers are special more expensive lines, that serve such purposes as TV games, fund collecting for charity companies, hot lines, etc. Basically a part of the extra money charged to the caller is sent to the owner of the line.

Often the abcd or even (xx)xabcd part of the number is chosen, if available, to form a word that is representative of the company holding the number.

Brazil

Brazil is divided into 67 two-digit geographical area codes, all of which with eight-digit numbers, in the format NNNN-NNNN, except for cell phones in areas codes from 11 to 28 as of December 2013 (until 2016 in all area codes), using nine-digit numbers, in the format 9NNNN-NNNN.

Peru

Peru uses 2-digit area codes followed by 6-digit subscriber numbers outside of Lima. In Lima the area code is "1" and the subscriber number has 7 digits, divided XXX XXXX. The "trunk 0" is often used, especially for numbers outside Lima. For example, a phone number in Arequipa might be written (054) XX-XXXX.

Cellphone numbers used to have 8 digits with the first digit always being 9. In 2008 an additional digit was added to cellphone numbers, while land numbers remained the same. The previous convention for cell numbers in Lima was usually 9XXX XXXX, though 9-XXX XXXX was also used. With the new 9-digit number, the form 9XX XXX XXX is becoming increasingly common as opposed to 9 XXXX XXXX, 9X XXX XXXX or 9XXXX XXXX.

Outside Lima cellphone numbers used to be 9 followed by six digits, i.e., 9 XXX XXX. The 2008 changes were somewhat more complicated. In four departments (similar to states), a 2 digit code now has to be entered before the 9. In the example of Arequipa, the code of 95 has to be entered before the 9, so the new numeration is 959 XXX XXX. The other codes are 94 for La Libertad (Trujillo), 96 for Piura and 97 for Lambayeque (Chiclayo). In the other 19 rural departments, the 9 is followed by the department's 2-digit area code then the 6-digit subscriber number. For example, the area code for Cusco is 84, so their new cellphone numeration is 984 XXX XXX. The effect is that all Peruvian cellphone numbers now have 9 digits; under the old system they had 8 digits in Lima and 7 everywhere else.

International Telecommunication Union

The International Telecommunication Union sector ITU-T issued recommendation E.123 entitled Notation for national and international telephone numbers, e-mail addresses and Web addresses.