9-1-1 - Cell Phones & Voice Over IP Service

9-1-1 & Cell Phones

Cell phones can be a valuable public safety tool. However, they also create unique challenges for public safety and emergency response personnel. No matter what you may have heard, we cannot determine the precise location of a caller who dials 9-1-1 from any cell phone. It is essential that you stay on the line and clearly give your location to the 9-1-1 call-taker.

FCC & Cellular Technology

The Federal Communications Commission (FCC) has taken a several steps to increase public safety by coordinating development of a nationwide, seamless communications system for emergency services that includes the provision of location information for wireless 911 calls. They have taken this approach in phases:
  • Phase 0 was the initial phase required by the FCC, which mandates that a caller can dial 911 from their cell phone.
  • Phase 1 mandates that cell phone carriers provide the telephone number of a wireless 9-1-1 caller and the location of the antenna (cell site) that received the call. This information is important in case the call is dropped and may allow the 9-1-1 call-taker to work with the wireless company to identify the wireless subscriber. The problem with Phase I is that it does not allow call-takers to locate emergency victims or callers.
  • Phase 2 mandates that carriers provide far more precise location information. Specifically, within 170 to 1000 feet. The various carriers have developed different methods to provide the latitude and longitude from the cell phone handset. It can be from triangulation, GPS, or a hybrid of the two.

Nash County 911 Operations Center

Nash County 911 Operations Center has upgraded its technology to Phase 2 standards. This doesn’t mean that your cell phone is capable of transmitting the necessary data necessary that we may need to get an approximate location. Your cell phone may be a Phase 1 compatible phone and not Phase 2. You should check with your provider to see if your phone is capable of sending the correct information.

Voice Over IP & 9-1-1

Voice over Internet Protocol (VoIP) is technology that uses the internet to transmit telephone calls rather than traditional landline technology. This new technology has many advantages for the consumer. However, it brings some serious concerns as well when calling 9-1-1.

VoIP Concerns

Since VoIP is transmitted over the internet, particular caller information may not be available or recognized by the (Enhanced 9-1-1) E9-1-1 system. The E9-1-1 system is the system that provides the 9-1-1 call-taker with Automatic Number Identification (ANI) and Automatic Number Location (ALI). This is the information provided on a landline call that displays the caller's phone number and from what address they are calling.

Also, VoIP calls are often misrouted to the wrong 9-1-1 center and frequently get dropped. Because of these two issues, it is possible that a VoIP caller may not get the assistance they need in times of an emergency.

Precautionary Measures

VoIP subscribers enjoy certain benefits that landline customers don’t. For instance, most VoIP customers get free long distance and cheaper local and cellular services. However, VoIP subscribers should also take certain precautionary measures to ensure they can call 9-1-1 without difficulties. Some of those measures are:
  • Maintain a landline telephone with minimal services, so you can take advantage of E9-1-1.
  • Maintain a landline as a backup due to power outages or internet difficulties.
  • Each VoIP provider may be different. Know your provider and the services that they offer.
  • Be sure to register the physical location where the phone will be used with the provider, so this information may be used when you call 9-1-1.
  • Be sure to re-register when you move as some providers take some time to update the records.
  • Remember when you use VoIP while mobile, the 9-1-1 center you called will be provided with the information you registered.
  • Test your VoIP with your local 9-1-1 center during slow times, preferably getting this approved by calling an administrative number first.
  • Keep your family updated on how your VoIP works and the limitation associated with it.


This is an informational site only. There is no way to get emergency help from this website. If you are experiencing an emergency, dial 9-1-1 from a cellular phone or a landline phone.