Editing Telephone numbering plan (section)

==International numbering plan==
Recommendation [[E.164]] by the [[International Telecommunication Union]] establishes an international numbering plan for routing telephone calls between countries. It defines a unique [[telephone country code]] with for each member organization, unless they are participating in an integrated numbering plan with other countries. Country codes are dialing prefixes to national telephone numbers and direct call routing to the network of a subordinate numbering plan administration. E.164 permits a maximum length of 15 digits for the complete international phone number consisting of the country code, the national routing code, such as an area code, and the subscriber number.  E.164 does not define regional numbering plans, however, it does provide recommendations for new implementations and uniform representation of all telephone numbers.

Country codes are necessary only when dialing telephone numbers in countries other than the originating telephone, but many networks permit them for all calls.

Following [[ITU-T]] specification [[E.123]], international telephone numbers are commonly indicated in listings by prefixing the country code with a plus sign ({{code|+}}). This reminds the subscriber to dial the [[list of international call prefixes|international access code]] of the country from which the call is placed. For example, the international dialing prefix or ''access code'' in all NANP countries is ''011'', and ''00'' in most other countries. On modern mobile telephones and many [[voice over IP]] services, the plus sign can usually be dialed and functions directly as the international access code.{{Ref RFC|6405}} [[Peer-to-peer SIP]] uses [[Dynamic Delegation Discovery System]] to perform endpoint discovery, and therefore [[E.164]] numbers.{{Ref RFC|6116}}

===Special services===
Within the system of country codes, the ITU has defined certain prefixes for special services. The ITU also assigns codes for independent international networks, such as satellite systems, spanning beyond the scope of regional authorities.

Some special international routing codes are the following:
* 388 5 – shared code for groups of nations
* 388 3 – [[European Telephony Numbering Space]] – Europe-wide services (discontinued)
* 800 – International Freephone ([[Toll-free telephone number|UIFN]])
* 808 – reserved for [[Shared Cost Service]]s
* 878 – [[Universal Personal Telecommunications]] services
* 881 – [[Global Mobile Satellite System]]
* 882 and 883 – International Networks
* 888 - international disaster relief operations
* 979 – [[International Premium Rate Service]]
* 991 – International Telecommunications Public Correspondence Service trial (ITPCS)
* 999 – reserved for future global service

===Satellite telephone systems===
[[Satellite phone]]s are typically issued with telephone numbers with a special country calling code, for example:
* [[Inmarsat]]: 870: SNAC (Single Network Access Code)
* [[ICO Global Communications|ICO Global]]: 881 0, 881 1
* Ellipso: 881 2, 881 3
* [[Iridium Satellite LLC|Iridium]]: 881 6, 881 7
* [[Globalstar]]: 881 8, 881 9
* Emsat: 882 13
* [[Thuraya]]: 882 16
* [[ACeS]]: 882 20
Some satellite telephones are issued with telephone numbers from a national numbering plan; for example, [[Globalstar]] issues NANP telephone numbers.

===Integrated telephone numbering plan===
In an '''integrated telephone numbering plan''' multiple countries share a single ITU country code. The North American Numbering Plan comprises 25 countries or dependent territories in North America and the [[Caribbean]]. Similarly, in eastern Europe and Asia, [[World Zone 7|world numbering zone 7]] comprises [[Telephone numbers in Russia|Russia]] and [[Telephone numbers in Kazakhstan|Kazakhstan]] with country code 7.