Telecommunications Relay Services
Telecommunications Relay Service (TRS or “relay service”) is a communication service that permits individuals with a hearing or speech disability to use the telephone system via a TTY, or other device, to call persons with or without such disabilities through a TRS relay center.
Different forms of relay service include Text-to-Voice TTY, Voice Carry Over (VCO), Hearing Carry Over (HCO), Speech-to-Speech (STS), Spanish Text-to-Voice TTY, Captioned Telephone, IP Captioned Telephone, IP Relay, and Video Relay Service (VRS). More information about the available types of relay service can be found on the FCC’s TRS website.
TRS is available in all 50 states and all U.S. territories for local and long-distance calls. TRS providers are compensated for the costs of providing TRS from either a state or a federal fund, and there is no charge to the TRS user other than standard calling rates.
Relay service can be reached by dialing 711 or by contacting your state relay provider, as listed in the FCC’s TRS Directory. In the event of an emergency, TTY users should call 911 directly.
T-Mobile TTY policy
A TTY, also known as a Text Telephone Device or Telecommunication Device for the Deaf (TDD), is a special device that enables people who are deaf, hard of hearing, or speech-impaired to use the telephone to communicate. TTY works by allowing people to type messages back and forth to one another instead of talking and listening. The device is required at both ends of the conversation.
The FCC requires digital wireless carriers to have the capability to transmit a call from a wireless phone that is connected to a TTY. While the FCC mandate pertains specifically to calls made to 911, the ability to make a call to 911 means users can also complete a call to anyone, anywhere, provided the party on the receiving end of the call also has a TTY.
TTY on T-Mobile's network
T-Mobile’s higher speed data services, including LTE, support use of IP-based TRS, including Video Relay Service, IP Relay, and IP Captioned Telephone Service through providers of those relay services. T-Mobile recommends use of these relay services as the most effective means of placing assisted calls, including to 911. If a T-Mobile customer nonetheless wants to use a mobile TTY, T-Mobile's GSM and UMTS cellular network is TTY compatible and may be used to reach 911. All T-Mobile price plans and most handset features will work with TTY. Customers will need to visit a T-Mobile retail store or contact Customer Service for assistance with selecting the proper rate plan and service activation.
Customers should be aware that TTY does not work on voice calls that are placed over Wi-Fi or Voice over LTE (VoLTE) at this time. This means that TTY calls, including TTY calls to 911, cannot be made while using IP-based calling, including Wi-Fi Calling and Voice over LTE. Customers with communications disabilities who need to call 911 while using IP-based calling should use IP Relay, Video Relay, or IP Captioned Telephone Service to reach emergency personnel. Where available, customers may also send a text message to 911 directly (text-to-911).
For more information, please view this short video about TTY on T-Mobile's network.