The FCCs wireless Enhanced 911 (E911) rules seek to improve the effectiveness and reliability of wireless 911 services by providing 911 dispatchers with additional information on wireless 911 calls. The FCCs wireless E911 rules apply to all wireless licensees, broadband Personal Communications Service (PCS) licensees, and certain Specialized Mobile Radio (SMR) licensees.
The Commission has divided its wireless E911 program into two parts - Phase I and Phase II. Under Phase I, the Commission requires carriers, within six months of a valid request by a local Public Safety Answering Point (PSAP), to provide the PSAP with the telephone number of the originator of a wireless 911 call and the location of the cell site or base station transmitting the call.
Under Phase II, the Commission requires wireless carriers, within six months of a valid request by a PSAP, to begin providing information that is more precise to PSAPs, specifically, the latitude and longitude of the caller. This information must meet FCC accuracy standards, generally to within 50 to 300 meters, depending on the type of technology used. The deployment of E911 requires the development of new technologies and upgrades to local 911 PSAPs, as well as coordination among public safety agencies, wireless carriers, technology vendors, equipment manufacturers, and local wireline carriers.
The FCC maintains a Master PSAP Registry  with information on PSAP names and locations.