About T-Mobile

About T-Mobile

Company Information

Company Information

9-1-1

Public Safety / 9-1-1

T-Mobile USA is committed to a partnership with Public Safety to provide the best possible 9-1-1 service for our subscribers and roaming customers in times of emergency.

What is Basic 9-1-1 service?

Basic 9-1-1 service is an emergency telephone system which automatically connects wireless 9-1-1 calls to a designated 9-1-1 Communications Center. Basic 9-1-1 may or may not provide the wireless phone’s 10-digit call-back number and estimated location. The handset must have battery power and be in a coverage area to complete a 9-1-1 call.

What is Enhanced 9-1-1 Phase I service?

Enhanced 9-1-1 Phase I service is the first step in providing better emergency response service to wireless 9-1-1 callers. Public Safety/9-1-1 Communications Centers need to send a letter to T-Mobile requesting Phase I service deployment at their agency. Once Phase I service has been implemented, when a wireless 9-1-1 call comes into the 9-1-1 Communications Center (also called a Public Safety Answering Point or PSAP), the call-taker's computer screen will show the wireless phone's 10-digit call-back number if one has been assigned to the calling handset. In the event the wireless phone call is dropped, the call-taker may contact the caller. Phase I service also identifies the cell site/sector location information that the call was originated on to the call-taker's computer screen. This provides the call-taker with a general location (i.e. within the site coverage area) of the caller. The handset must have battery power and be in a coverage area to complete a 9-1-1 call.

What is Enhanced 9-1-1 Phase II service?

Public Safety/9-1-1 Communications Centers need to send a letter to T-Mobile requesting Phase II service deployment at their agency. With Phase II service, the location information that is provided to the 9-1-1 Communications Center is the approximate X, Y (longitude, latitude) location of the handset making the 9-1-1 call. This location information is typically more accurate than the Phase I location information (cell site/sector). As with Phase I, Phase II service allows call-takers to receive both the caller's wireless phone number and their estimated location information. Since early 2004, T-Mobile has been deploying Phase II services. T-Mobile utilizes a hybrid solution, referred to as U-TDOA, Uplink-Time Difference of Arrival and AGPS, Assisted Global Positioning System, to provide an estimated Phase II location to the 9-1-1 Communications Center. The handset must have battery power and be in a coverage area to complete a 9-1-1 call.

What is Text to 9-1-1 service?

Placing a voice call to 9-1-1 is your best option during an emergency. At this time, some 9-1-1 Centers are able to receive and/or respond to text messages sent to 9-1-1 via a T-Mobile handset. If a customer attempts to send a text to 9-1-1 in an area where the service is not available, an auto-reply message will be sent to the handset stating:

“Please make a voice call to 911. There is no text service to 911 available at this time in this area. This is a free message.”

T-Mobile entered into a voluntary agreement to begin the deployment of Text to 9-1-1 service starting in mid-2014. Public Safety/9-1-1 Communications Centers will need to send a letter to T-Mobile requesting Text to 9-1-1 service deployment at their agency once they are ready to receive text messaging. Please note, making a voice call to 9-1-1 is still the most efficient way to contact emergency services.

T-Mobile's public education efforts

T-Mobile is committed to educating our customers about mobile phones and 9-1-1. On T-Mobile.com and in materials sent directly to customers we also address issues such as accidental calls to 9-1-1. The State of Washington's 9-1-1 Office created these brochures: 

Accidental 9-1-1 calls
9-1-1 llamadas accidentales
What's Your Location 

Remember…when calling 9-1-1 during an emergency:

Stay calm and speak clearly.

Do not hang up until the 9-1-1 call taker has obtained all of the information that is needed.

Since you are calling from a wireless phone, your call may be disconnected if the signal is lost. Be sure to call 9-1-1 back if you are cut off. If you are driving, consider pulling off the road and stopping the vehicle to complete the 9-1-1 call.

Your 9-1-1 call may need to be transferred to another agency.



Frequently Asked Questions       


As a T-Mobile subscriber, do I need to sign up for Phase I and II service? 
How do I know whether Phase I or Phase II services have been deployed in a particular area where I’m making wireless calls? 
Once a Public Safety/9-1-1 Communication Center requests Phase I and II service from T-Mobile, how long does it take to have the service available? 
Do I need to purchase an upgraded handset in order for Phase I and II services to work? 
What happens when I call 9-1-1 from my wireless handset? 
I have T-Mobile prepaid service, can I still reach 9-1-1? 
I kept my phone number from a different state when I moved. When I dial 9-1-1 from my T-Mobile handset, will my call be routed to the closest 9-1-1 center? 
What should I do if I accidentally dial 9-1-1? 
If I have subscribed to WiFi Calling service, do I need to register the location of my device for 9-1-1 purposes? 
What level of 9-1-1 service will I receive using WiFi Calling service? 
What level of 9-1-1 service will I receive using my WiFi Calling handset when I am away from my registered location? 
Are there any limitations to using TTY to contact 9-1-1? 
Is it necessary to “test” my handset/service by calling 9-1-1 when I do not have an emergency? 
Where can I get additional information on Public Safety/ 9-1-1? 

As a T-Mobile subscriber, do I need to sign up for Phase I and II service?             

No. The Public Safety/9-1-1 Communications Center serving a particular area requests the service from T-Mobile, not the subscriber. Once the service is requested by the 9-1-1 Communications Center and deployed by T-Mobile, it is provided for all the T-Mobile network users in that area. T-Mobile has deployed Enhanced 9-1-1 Phase I and Phase II service throughout much of the country.

How do I know whether Phase I or Phase II services have been deployed in a particular area where I’m making wireless calls?

Because there are over 6,100 9-1-1 Communications Centers in the United States, we suggest you contact the 9-1-1 Center in your area by calling their non-emergency/administrative phone number (usually found near the front of the local phone book or directory) to determine that agency's ability to receive wireless Enhanced 9-1-1 calls.

Once a Public Safety/9-1-1 Communication Center requests Phase I and II service from T-Mobile, how long does it take to have the service available?

The Federal Communications Commission has mandated wireless carriers to deploy Phase I and II services within 6 months of a request from the Public Safety/9-1-1 Communications Center. Occasionally, this timeline is adjusted per mutual agreement.

Do I need to purchase an upgraded handset in order for Phase I and II services to work?

No. T-Mobile’s Phase II solution does not require subscribers upgrade or change their handset. The level of service is the same regardless of whether you are a postpaid, Monthly4G or prepaid subscriber. Note for Monthly4G and prepaid subscribers: If your call to 9-1-1 is disconnected for some reason and there is a need for the 9-1-1 Communications Center to call you back, you will need to have minutes available on your account for the return call to be completed.

What happens when I call 9-1-1 from my wireless phone?

The T-Mobile network will route your 9-1-1 call to the designated 9-1-1 Communications Center (also called a Public Safety Answering Point or PSAP). When your call is answered by the 9-1-1 dispatcher, be ready to answer questions such as: 1. Where is the emergency? Provide highway name, direction of travel, mile marker, intersection, etc. 2. What number are you calling from? Always give your area code and wireless phone number. 3. What exactly has happened? Clearly describe what has taken place.

I have T-Mobile prepaid service, can I still reach 9-1-1?

Yes. All T-Mobile handsets can process 9-1-1 calls, regardless if you are a Monthly4G or prepaid subscriber, or a contract subscriber. The phone must have battery power and be in a coverage area to complete a 9-1-1 call. If your call to 9-1-1 is disconnected for some reason and there is a need for the 9-1-1 Communications Center to call you back, you will need to have minutes available on your account for the return call to be completed.

I kept my phone number from a different state when I moved. When I dial 9-1-1 from my T-Mobile handset, will my call be routed to the closest 9-1-1 center?

Yes. The T-Mobile network will route your 9-1-1 call to the designated 9-1-1 Communications Center, regardless of the 10-digit phone number assigned to the phone. Be sure to provide your area code with your phone number to the 9-1-1 dispatcher.

What should I do if I accidentally dial 9-1-1?

You should stay on the line until the 9-1-1 dispatcher has answered the call and indicate the call was made by mistake and no emergency assistance is needed.

If I have subscribed to WiFi Calling service, do I need to register the location of my device for 9-1-1 purposes?

Yes. You will be asked to supply a street address at which the WiFi Calling service will be used. The registered location you provide may be used to help emergency responders locate you after you complete a 9-1-1 call using this service. This location information should be updated if you use this service at a different location. Your location information can be provided and/or updated by accessing your account at MyT-Mobile.com or by contacting T-Mobile Customer Care.

What level of 9-1-1 service will I receive using WiFi Calling service?

When you make a 9-1-1 call with a WiFi Calling enabled phone, your phone will first attempt to complete the call like any other phone in the T-Mobile network. Depending on the capabilities of your local 9-1-1 Communications Center, you may receive Wireless Enhanced Phase I, Phase II, or Basic 9-1-1 service as described above. T-Mobile works very closely with the 9-1-1 Communication Centers to deploy the best possible 9-1-1 service supported by the 9-1-1 Communication Centers. If you are at your registered location (as described above) and wireless coverage is unavailable, your phone will try to complete the 9-1-1 call using special WiFi Calling functionality. Your location is one of a number of methods which may be used to route your 9-1-1 call and provide your location to the designated 9-1-1 Communications Center. Therefore, it is very important to keep the registered address information current. Your location information can be provided and/or updated by accessing your account at My T-Mobile or by contacting T-Mobile Customer Care.

What level of 9-1-1 service will I receive using my WiFi Calling handset when I am away from my registered location?

If you are accessing WiFi Calling service at a T-Mobile HotSpot and wireless coverage is unavailable, the 9-1-1 call will be routed to the designated 9-1-1 Communications Center serving that location. If you are using a WiFi Calling enabled phone via an access point other than the one associated with your existing registered location, it is important for you to update that information with your new address by accessing your account at My T-Mobile or by contacting T-Mobile Customer Care. When you return to your prior location, you will need to update your registered location again.

Are there any limitations to using TTY to contact 9-1-1?

Calls to 911 from a TTY will not work when using WiFi Calling or Voice over LTE. If you are deaf or hard of hearing and need assistance in communicating over the telephone, T-Mobile recommends that you use an internet-based Telecommunications Relay Service such as Video Relay Service, IP Relay Service or IP Captioned Telephone Service, including for calls to 911. T-Mobile’s HSPA+ and LTE data services can support these relay services. For more information, see www.t-mobile.com/accessibilitypolicy

Is it necessary to test my handset/service by calling 9-1-1 when I do not have an emergency?

No. Please do not call 9-1-1 to simply test the system. T-Mobile works very closely with the 9-1-1 Communication Centers to deploy the best possible 9-1-1 service. Please be sure to register and update the location of your service as described above.

Where can I get additional information on Public Safety/ 9-1-1?

Federal Communications Commission 
National Emergency Number Association 
Association of Public-Safety Communications Officials 
Emergency Services Interconnection Forum

Contact information for Public Safety and 9-1-1 Communications Centers ONLY


Please note: Any correspondence that is sent to the 9-1-1 Regulatory Team that is meant for T-Mobile Customer Care will not be answered. See Customer Care contact information


For subpoena requests

Fax: 973-292-8697

Law Enforcement Relations

Phone: 973-292-8911

For 9-1-1 network issues

Phone: 1-888-662-4662

Regulatory Team contact information

Phase I and Phase II request letters should be addressed to the 9-1-1 Regulatory Manager at the address below. To expedite the processing of the request letter, please:

Send the original request letter via US Mail or by courier service to: 
T-Mobile 9-1-1 Regulatory Manager 
601 Pennsylvania Avenue NW
North Building Suite 800
Washington DC, 20004