|Country calling code||+670|
|International call prefix||00|
Until September 1999, East Timor formed part of the Indonesian numbering plan, using the country code +62, followed by area codes for the two largest cities, Dili (390)and Baucau (399). Following the violence in the wake of Indonesia's departure from the territory, most of the telecommunications infrastructure was destroyed, and Telkom Indonesia withdrew its services from East Timor.
In the interim, the code +672, used by the Australian External Territories, was used to reach numbers in the territory.Originally, the +672 code had been allocated to the then Portuguese Timor, before its invasion and occupation in 1975.
A new country code, +670, was allocated to East Timor, but international access often remained severely limited. A complicating factor is that 670 was previously used by the Northern Marianas, with many carriers not aware that the code is now used by East Timor, and that the Northern Marianas, now part of the North American Numbering Plan, use the code 1 and the area code 670 instead, although calls to the Northern Marianas from the US are billed as calls to East Timor.
East Timor now has a closed numbering plan; all fixed line subscribers' numbers are seven digits, while mobile phone subscribers' numbers are now eight digits, with a '7' being added to the old seven-digit number.
Telephone numbering in East Timor is as follows:
|List of area codes|
|22X XXXX||Cova Lima|
|31X XXXX||Dili (reserve)|
|32X XXXX||Dili (reserve)|
|33X XXXX||Dili (initial)|
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.
Telephone numbers in the United Kingdom are administered by the UK government's 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.
The Australian telephone numbering plan describes the allocation of phone numbers in Australia. It has changed many times, the most recent major reorganisation by the Australian Communications and Media Authority taking place between 1994 and 1998.
Telephone numbers in Hong Kong are mostly eight-digit. Fixed land line numbers start with 2 or 3, mobile (cellular) phone numbers with 5, 6, 7 or 9, pager numbers with 7 and forwarding service with 8. Since the end of 1989, there have been no area codes within Hong Kong.
The Big Number Change addressed various issues with the telephone dialling plan in the United Kingdom, during the late-1990s and early-2000s.
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.
Widespread UK telephone code misconceptions, in particular brought on by the Big Number Change in 2000, have been reported by regulator Ofcom since publication of a report it commissioned in 2004.
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.
0191 is the UK telephone dialling code used by Newcastle, Durham, Sunderland and other nearby areas in the north east of England.
PhONEday was a change to the telephone dialling plan in the United Kingdom on 16 April 1995. It changed geographic area codes and some telephone numbers. In most areas, a "1" was added to the dialling code after the initial zero. In Bristol, Leeds, Leicester, Nottingham and Sheffield, the area codes were replaced with new codes and the subscriber numbers gained an extra digit. The PhONEday changes also made provision for new ranges of subscriber numbers in those five cities. A £16m advertising campaign, and an eight-month period of parallel running during which old and new codes were active, preceded the change. PhONEday followed a change made in May 1990, when the old London area code 01 had been released from use, permitting all United Kingdom geographic numbers to begin with this prefix. Originally planned in 1991 to take place in 1994, in 1992 the change was postponed until 1995.
The regulation of telephone numbers in Germany is the responsibility of the Federal Network Agency of the German government. The agency has a mandate to telecommunications in Germany and other infrastructure systems.
The national conventions for writing telephone numbers vary by country. While international standards exist in the form of the International Telecommunication Union sector ITU-T issued recommendation E.123, national telephone numbering plans define the format and length of telephone numbers assigned to telephones.
Namibia's telephone numbering plan was originally devised when the country, then known as South West Africa, was under South African administration, and integrated into the South African telephone numbering plan.
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:
Telephone numbers in the United Kingdom have a flexible structure that reflects their historical demands, starting from many independent companies through a nationalised near-monopoly, to a system that supports many different services, including cellular phones, which were not envisaged when the system was first built. Numbers evolved in a piecemeal fashion, with numbers initially allocated on an exchange-by-exchange basis for calls connected by manual operators. Subscriber numbers reflected demand in each area, with single digit telephone numbers in very rural areas and longer numbers in cities.