TTY Service – Relay Services for Deaf Communication
TTY service refers to the telecommunications relay system that connects Deaf, hard-of-hearing, and speech-disabled individuals with hearing callers through text-based telephone communication. Whether you are a Deaf person using a teletypewriter or a hearing person receiving a relay call, understanding how TTY service works helps ensure smooth, respectful, and effective communication across the hearing divide.
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What Is TTY Service
TTY service is a federally mandated telecommunications relay system that bridges communication between TTY users and voice telephone users. When a Deaf person using a teletypewriter needs to call someone who uses a standard voice phone, the TTY service provides a trained communication assistant who relays the conversation in real time — typing what the hearing party says and voicing what the Deaf party types.
The legal foundation for TTY service comes from Title IV of the Americans with Disabilities Act, which requires all telephone companies to provide relay services 24 hours a day, 365 days a year at no additional cost to the caller. Before the ADA mandate, relay services existed in some states but coverage was inconsistent. The ADA created a nationwide standard that guaranteed every American could access relay services from any telephone.
To access TTY service, callers simply dial 711, the national relay access number established by the Federal Communications Commission in 2001. This three-digit number works from any phone — landlines, cell phones, and payphones — routing the call to the appropriate relay service provider for the caller’s region.
TTY service is more than a convenience — it is a civil right. The ability to make phone calls independently and privately is fundamental to participation in modern society, from scheduling medical appointments to conducting business to reaching emergency services. TTY service ensures that hearing status does not determine access to this essential function.
How TTY Relay Service Works
The mechanics of a TTY relay call are straightforward. The TTY user dials 711, and a communication assistant answers. The user types the phone number they want to reach and any special instructions, such as requesting a male or female assistant or specifying the communication mode they prefer.
The communication assistant then dials the hearing party. When they answer, the assistant explains that they are facilitating a relay call and asks the hearing person to speak normally. As the hearing person talks, the assistant types their words in real time, and the text appears on the TTY user’s screen. When the TTY user types a response, the assistant reads it aloud to the hearing party.
Communication assistants follow strict professional standards. They relay everything verbatim — they do not summarize, edit, or add their own opinions. They maintain complete confidentiality, meaning they cannot disclose any information about the content of relay calls even after the call ends. These standards are enforced by the FCC and are essential to maintaining the trust and privacy that TTY service users expect.
Relay calls naturally take longer than direct voice calls because of the typing and reading involved. A call that might take five minutes voice-to-voice could take ten to fifteen minutes through relay. Both parties can help by speaking clearly, using straightforward language, and being patient with the pace. The quality of communication is worth the extra time it takes to talk through relay.
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Types of TTY Relay Services
TTY service encompasses several different relay modes designed to accommodate various communication needs and abilities. Traditional TTY relay is the standard format where the user types messages on a TTY device and the communication assistant voices them to the hearing party, and vice versa.
Voice Carry Over is designed for individuals who can speak clearly but cannot hear well enough to understand speech over the phone. In VCO mode, the caller speaks directly to the hearing party using their own voice, and the communication assistant types the hearing party’s responses for the caller to read on their TTY screen. This mode is particularly popular among late-deafened adults who retain natural speech patterns.
Hearing Carry Over serves the opposite need — individuals who can hear but have speech difficulties. The user types their messages, which the assistant voices to the hearing party, while the user listens directly to the hearing party’s spoken responses. This service supports people with conditions that affect speech production, such as stroke, cerebral palsy, or laryngectomy.
Speech-to-Speech relay assists callers with speech that may be difficult for unfamiliar listeners to understand. A specially trained assistant listens to the caller and revoices their words more clearly. This service is valuable for people whose speech is intelligible to family and close contacts but challenging for strangers to follow.
Internet Protocol Relay uses internet connections instead of traditional phone lines for the text portion of the call. IP Relay is faster than Baudot-based TTY because it uses modern data protocols, and it allows users to make relay calls from any internet-connected device without dedicated TTY hardware. This option has become increasingly popular as broadband internet has become more widely available.
Your Rights Under Federal Law
Federal law provides robust protections for TTY service users. Title IV of the ADA requires telecommunications carriers to provide relay services at no charge, 24 hours a day. The FCC enforces quality standards including maximum call setup times, operator qualifications, and confidentiality requirements.
Businesses are legally prohibited from refusing relay calls. Under the ADA, any business that accepts voice phone calls must also accept relay calls. A business cannot provide inferior service, impose longer hold times, or refuse to complete a transaction simply because the call is facilitated through relay. If you experience discrimination when making a relay call, you can file a complaint with the FCC or the Department of Justice.
Relay users have the right to request specific accommodations from the relay service itself. You can ask for a communication assistant of a particular gender, request that the assistant type everything including background noises and speaker identification, or specify your preferred communication mode. These options help customize the relay experience to your individual needs.
State telecommunications commissions also oversee relay services and may offer additional protections or services beyond the federal minimums. Some states provide enhanced relay services, equipment distribution programs, or specialized services for DeafBlind users. Contacting your state’s commission for the deaf or telecommunications relay advisory council can help you learn about all the services available in your area and how to access them.
The Future of TTY Service
TTY service continues to evolve alongside telecommunications technology. Video Relay Service has become the dominant form of relay for Deaf ASL users, offering a more natural communication experience through sign language interpreters. VRS calls are faster and more expressive than text-based relay, and they allow Deaf individuals to use their primary language rather than typed English.
Real-Time Text technology is emerging as a potential successor to traditional Baudot-based TTY. RTT transmits text character by character as it is typed, rather than requiring the user to complete a line before sending. This creates a more fluid, conversation-like experience that is closer to instant messaging. The FCC has been working to integrate RTT into the relay service framework while maintaining backward compatibility with existing TTY devices.
Captioned telephone services have also grown significantly. These services provide real-time captions of the hearing party’s speech, displayed on a screen attached to the phone. The user speaks directly with their own voice and reads captions of the other person’s responses. This approach is especially appealing to people with mild to moderate hearing loss who do not identify as Deaf or use ASL.
Despite these advances, traditional TTY service is not disappearing. The FCC continues to require TTY relay as a baseline service, recognizing that not everyone has access to broadband internet, video equipment, or the latest smartphone technology. TTY service remains the most universally accessible form of relay, functioning over any telephone line without requiring internet connectivity. For as long as there are individuals who depend on text-based telephone communication, TTY service will continue to play an essential role in telecommunications accessibility.
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