A telephone numbering plan is a type of numbering scheme used in telecommunication to assign telephone numbers to subscriber telephones or other telephony endpoints. Telephone numbers are the addresses of participants in a telephone network, reachable by a system of destination code routing. Telephone numbering plans are defined in each of the administrative regions of the public switched telephone network (PSTN) and in private telephone networks.
In the United Kingdom, telephone numbers are administered by the Office of Communications (Ofcom). For this purpose, Ofcom established a telephone numbering plan, known as the National Telephone Numbering Plan, which is the system for assigning telephone numbers to subscriber stations.
South Africa switched to a closed numbering system effective 16 January 2007. At that time, it became mandatory to dial the full 10-digit telephone number, including the zero in the three-digit area code, for local calls. Area codes within the system are generally organized geographically. All telephone numbers are 9 digits long, except for certain Telkom special services. When dialed from another country, the "0" is omitted and replaced with the appropriate international access code and the country code +27.
Numbers on the Irish telephone numbering plan are regulated and assigned to operators by ComReg.
Telephone numbers in Singapore, also known as the National Numbering Plan, are regulated by the Info-communications Media Development Authority (IMDA). Due to the small geographical size of Singapore, there are no area or trunk codes; all numbers belong to one numbering area, and thus come in the same 8-digit format. Numbers are categorised based on the first digit, thus providing ten possible categories, of which six are currently in use and the remaining four reserved for future usage.
Telephone numbers in Switzerland are defined and assigned according to the Swiss telephone numbering plan administered by the Swiss Federal Office of Communications. The plan has been changed several times and the most recent reorganization was implemented in March 2002.
Telephone numbers in South Korea are organized and assigned using the following scheme
Telephone numbers in Oceania use a variety of area codes to denote their location along with their own area code depending on the country's geographic makeup. They also have other prefixes to denote different types of mobile services and international calls. There are exceptions because of regional variations and time zones.
Telephone numbers in Malaysia are regulated by the Malaysian Communications and Multimedia Commission (MCMC).
The format of telephone numbers in Australia has changed over time to allow for the expansion of the subscriber base as technology has improved.
Telephone numbers in Luxembourg employ a closed dialling system, whereby all numbers are dialed in the same format whether from within Luxembourg or from abroad. There is no trunk prefix like "0".
Telephone numbers in Israel consist of an area code and a subscriber number. The dial plan type in Israel is closed, and "0" is the internal Trunk prefix in Israel. Israel's country calling code is +972.
Slovenia received a new country code following the breakup of the Socialist Federal Republic of Yugoslavia in 1991. Additionally, the Ipko mobile phone company in Kosovo used the +386 country code.
A telephone number in Belgium is a sequence of nine or ten digits dialed on a telephone to make a call on the Belgian telephone network. Belgium is under a full number dialing plan, meaning that the full national number must be dialed for all calls, while it retains the trunk code, '0', for all national dialling.
National conventions for writing telephone numbers vary by country. The International Telecommunication Union (ITU) publishes a recommendation entitled Notation for national and international telephone numbers, e-mail addresses and Web addresses. Recommendation E.123 specifies the format of telephone numbers assigned to telephones and similar communication endpoints in national telephone numbering plans.
All telephone numbers in Panama are seven or eight digits long and there are no area codes. All numbers that both begin with 6 and have 8 digits are mobile numbers. All landline numbers have 7 digits. The first digit of landline numbers may be used to vaguely identify the location of the caller. Mobile phones were also assigned 7 digit numbers until 2005, when they were moved to their own number space with 8 digits. Mobile numbers are recycled if the user is marked as inactive by the mobile service provider, and landline numbers are also recycled if a user cancels their landline phone service.
Eswatini, then known as Swaziland, was allocated the country code +268 by the International Telecommunication Union, in the late 1960s. To call a telephone number in Eswatini, the following format is used:
The Belize telephone numbering plan is the system used for assigning telephone numbers in Belize.
