Local Number Portability

Local number portability (LNP) for fixed lines, and full mobile number portability (FMNP) for mobile phone lines, refers to the ability of a "customer of record" of an existing fixed-line or mobile telephone number assigned by a local exchange carrier (LEC) to reassign the number to another carrier ("Service Provider Portability"), move it to another location ("Geographic Portability"), or change the type of service ("Service Portability"). In most cases, there are limitations to transferability with regards to geography, service area coverage, and technology. Location Portability and Service Portability are not consistently defined or deployed in the telecommunication industry.

In the United States and Canada, mobile number portability is referred to simply as WNP or WLNP (Wireless LNP). In the rest of the world it is referred to as mobile number portability (MNP). Wireless Number Portability is available in some parts of Africa, Asia, Australia, Latin America and most European countries including Britain; however, this relates to transferability between mobile phone lines only. Canada and the United States are the only countries that offer full number portability transfers between both fixed lines and mobile phone lines, because mobile and fixed line numbers are mixed in the same area codes, and are billed identically for the calling party, the mobile user usually pays for incoming calls; in other countries all mobile numbers are placed in higher priced mobile-dedicated area codes and the originator of the call to the mobile phone pays for the call. The government of Hong Kong has tentatively approved fixed-mobile number portability; however, as of July 2012, this service is not yet available.

Some cellular telephone companies will charge for this conversion as a regulatory cost recovery fee.