Location routing number

A Local Routing Number (or LRN) is ten digit number that looks like a telephone number, but in actuality represents an entire telephone switch through which multiple telephone numbers are routed.

Background

In 1996, the US Congress mandated a change in local telephone service that allows any carrier to enter a local market. The new regulation provides for local number portability (LNP), which means that when a consumer’s phone service is moved from one service provider to another, the telephone number (TN) does not change. This process is called porting a number.

The Location Routing Number (LRN) identifies the switch for Local Number Portability (LNP). Every ported TN must have an LRN assigned to it. An LRN is a 10-digit number that looks like a TN and represents the entire switch through which multiple TNs are routed. Individual TNs are mapped to an LRN (the mapping of TNs to an LRN is referred to as a ‘subscription’.)

Virginia based NeuStar (acting as a neutral party) has been chartered with developing and maintaining the Number Portability Administration Center (NPAC) to support the implementation of Local Number Portability (LNP).