TTY relay services (also known as 711) are text-to-voice and voice-to-text relay services. In a TTY relay service call, the relay operator communicates with the person who has a hearing or speech disability via TTY (typewritten messages), and with the person without a hearing or speech disability via voice. GETUS customers are able to make TTY calls free of charge, 24/7, 365 days a year. Access to TTY requires a TTY device.