- A textphone, historically branded Minicom, sends typed characters as tones over an ordinary analogue landline line, displaying the conversation on a small screen.
- Relay UK, commissioned by BT under an Ofcom universal service obligation, is the modern relay service that has largely replaced standalone textphone hardware.
- Ofcom's General Conditions require every UK communications provider to give access to a relay service for deaf, hard-of-hearing and speech-impaired customers.
- Older textphones rely on the analogue PSTN, which Openreach is retiring as the network migrates to all-IP by 2027.
- Relay UK can be reached by dialling the prefix 18001 before a number, or through the free Relay UK app on a smartphone, tablet or computer.
A textphone or minicom lets a deaf user type and read text over a landline. Most users now move to Relay UK, the free relay service every UK provider must support.
Last reviewed: June 2026
What a Textphone or Minicom Actually Is
For decades, a textphone was the standard way for deaf, hard-of-hearing and speech-impaired people in the United Kingdom to use the telephone network. The device looks like a chunky telephone with a built-in keyboard and a single-line or two-line text display. Minicom became the most recognised brand name, to the point where many people use minicom and textphone interchangeably, in the same way that hoover came to mean any vacuum cleaner. In practice the words describe the same category of equipment.
The core idea is simple. Instead of speaking and listening, the user types a message that is converted into audio tones and sent down the line. At the far end, a compatible textphone decodes those tones back into readable characters. When both people in a conversation have a textphone, they can hold a full typed exchange across the ordinary telephone network without any speech at all. The hardware was designed to work on the same copper line that carried voice calls, so no special broadband connection was needed.
How a Textphone Works Over a Landline
A traditional textphone uses a signalling method based on the international Baudot, or TTY, tone protocol. Each letter typed on the keyboard is translated into a pair of audio frequencies. These tones travel over the analogue Public Switched Telephone Network in exactly the way a fax machine or an old dial-up modem sends data: as sound carried on a voice-grade line. The receiving device listens for the tones and reconstructs the text on its screen.
Because the system rides on standard voice frequencies, a textphone can be plugged into a normal telephone socket and used to dial any number. The limitation is that meaningful text-to-text conversation requires compatible equipment, or a relay operator, at the other end. To bridge calls between a textphone user and a hearing person who only has voice, a relay service has always been essential. That is where the relay operator types what the hearing caller says and reads back what the textphone user types.
Relay UK: The Modern Replacement
Relay UK is the current national relay service, run by BT under an obligation overseen by Ofcom. It performs the same bridging role that relay operators have always provided, but it no longer depends on owning a dedicated textphone. A user can connect through the free Relay UK app on a smartphone, tablet or computer, typing their side of the conversation while a relay assistant voices it to the hearing person and types the spoken replies back.
Relay UK still supports legacy textphone hardware for people who prefer it, by dialling the 18001 prefix before the number being called. This routes the call through a relay assistant. The shift from standalone minicom boxes to an app-based service matters because of the wider network change: Openreach is retiring the analogue PSTN as the country moves to all-IP telephony by 2027. App-based and IP-friendly relay access is designed to keep working once the old copper voice service is switched off.
Textphone Compared With Relay UK
The table below summarises how the older textphone approach compares with the modern Relay UK service across the points that matter most to users.
| Feature | Textphone / Minicom | Relay UK |
|---|---|---|
| Hardware needed | Dedicated textphone device | App on phone, tablet or PC, or a textphone via 18001 |
| Network used | Analogue PSTN landline | Internet or landline |
| Relay operator | Required to call hearing people | Built into the service |
| PSTN switch-off impact | Affected as analogue retires by 2027 | Designed for all-IP use |
| Cost to access | Device purchase plus call charges | Free app; calls charged as standard |
What Providers Must Support
Ofcom's General Conditions of Entitlement place a duty on communications providers to make sure deaf, hard-of-hearing and speech-impaired customers can use the phone. In practice this means every provider must give access to an approved relay service and must not charge disabled users more overall for the equivalent of a voice call once relay time is taken into account. Providers are also expected to publish accessible information about how to reach the relay service.
The universal service framework means a national relay capability has to exist regardless of which provider a customer chooses. So whether a household is with a large operator or a smaller reseller, access to Relay UK should be available. Customers who still rely on a physical textphone should tell their provider, because the move to all-IP services may affect how legacy equipment behaves on a new digital line.
How to Get a Textphone or Move to Relay UK
Anyone who wants to start using the relay service can download the Relay UK app at no cost from BT, or use the 18001 prefix from a compatible textphone. There is no separate subscription for the relay function itself, although the underlying call is charged at the normal rate for that number by the user's own provider. People who prefer dedicated hardware, or who support someone who finds an app difficult, can still source textphone equipment, but should check how it will work on a digital line.
Charities and local authority sensory teams have historically helped people obtain textphone equipment and learn to use relay services, and contacting a provider's accessibility team is a sensible first step. As the analogue network is withdrawn, the practical direction of travel is towards app-based and IP-compatible access, so users setting up for the first time may find the app the most future-proof route.
Frequently Asked Questions
What is a textphone?
A textphone is a telephone with a keyboard and a text display that lets a deaf, hard-of-hearing or speech-impaired person type and read a conversation instead of speaking and listening. It sends typed characters as audio tones over the telephone line. When the other person does not have a textphone, a relay operator bridges the call.
Can I still use a minicom in the UK?
A minicom can still be used, and the relay service supports legacy textphone hardware through the 18001 dialling prefix. However, the analogue network these devices were built for is being retired as the United Kingdom moves to all-IP telephony by 2027. Users should check with their provider how an older minicom will behave on a digital line.
What is replacing textphones?
Relay UK, the national relay service run by BT under Ofcom oversight, has largely replaced standalone textphone hardware. It provides the same operator-bridged conversations through a free app on a smartphone, tablet or computer, as well as supporting traditional textphones. This app-based approach is designed to keep working after the analogue network is switched off.
How does Relay UK work?
With Relay UK, the deaf or speech-impaired user types their side of a conversation while a relay assistant reads it aloud to the hearing person and types the spoken replies back to the screen. It can be accessed through the Relay UK app or by dialling 18001 before a number on a textphone. The relay assistant stays neutral and relays everything said.
Is a textphone the same as a minicom?
Yes, in everyday use the two terms describe the same kind of device. Minicom was a popular brand of textphone, and the name became a generic label in much the same way that other brand names became generic terms. Both refer to a telephone with a keyboard and display used to hold typed conversations over the line.
