Telephony copper plant retirement in the United Kingdom

As in many other countries, the United Kingdom is retiring its part of the global circuit-switched public switched telephone network.

British Telecom, the country's dominant telco, announced its intention to switch off its PSTN infrastructure by December 2025, including both copper baseband landline telephone connections and its ISDN network. Openreach, the major telecommunications infrastructure provider in the United Kingdom, is also due to retire its Wholesale Line Rental service.

This process has been planned since 2017, and will roll out in a series of phases. All providers are expected to implement Voice over IP and other IP-based network services to replace copper PSTN and ISDN connections.

PSTN switch-off
All major British telcos. including other Broadband Stakeholder Group companies such as Virgin Media and Sky UK that have their own infrastructure, will also cease to support both copper PSTN and fibre ISDN connections. Instead, analog landline telephones will be expected to connect to adaptors on home routers, and businesses connecting to the PSTN via ISDN connections will be expected to move to SIP connections to the VoIP network, a transition that has already been performed by many companies.

Voice telephony will continue to follow the E.163 and E.164 standards, as with current mobile telephony, with the interface to end-users remaining the same. Traditional analog telephones will continue to operate via traditional analog phone sockets, but with those phone sockets now terminating at the on-premises router or PBX. No changes will need to be made to the mobile phone networks, which already interconnect via data networking technologies.

Retirement of the copper last-mile access network
Copper landlines will continue to be used for ADSL and VDSL Internet access for the time being. Fibre to the premises Internet access is planned to be rolled out nationally, allowing the eventual retirement of the entire copper telephone network. BT Openreach's copper plant has been reported to have billions of pounds of scrap value, even after accounting for the cost of removal, with over a million tonnes of copper buried under the streets. Full retirement of the copper access network is expected to stretch into the 2030s.

One problem with the replacement of the copper last mile is the discontinuation of electrical power to devices via the phone network, including critical devices such as health monitors. Work is in progress to address these problems.