- Openreach is retiring the Public Switched Telephone Network (PSTN) and migrating all voice services to internet protocol, with the all-IP migration completing in 2027.
- After migration, traditional analogue phone lines are replaced by digital voice carried over a broadband connection rather than the legacy copper switching network.
- Ofcom requires communications providers to protect customers, including a free battery back-up unit for those who rely solely on a landline or use telecare devices.
- The change affects any device plugged into the phone line, including alarms, telecare pendants, payment terminals and lift emergency lines, not just the telephone handset.
- Communications providers, not Openreach directly, are responsible for contacting their own customers about the migration and arranging the move.
The PSTN switch-off is the retirement of the UK copper analogue phone network. Voice services move to digital voice over broadband, with the all-IP migration completing in 2027. Your provider arranges the change.
Last reviewed: June 2026
What the PSTN switch-off actually is
For more than a century, UK phone calls have travelled across the Public Switched Telephone Network, a vast web of copper wires and mechanical and electronic exchanges that connect one caller to another. That network is now being decommissioned. In its place, voice calls are delivered as data over a broadband line using internet protocol, the same underlying technology that already carries email, streaming and web traffic. The industry shorthand for this transition is the all-IP migration, and it is sometimes described loosely as the big switch-off or the analogue switch-off.
The change is led by Openreach, the company that maintains the physical access network in most of the country, working alongside the communications providers that sell phone and broadband services to the public. Openreach has confirmed that the legacy PSTN will be withdrawn and that the all-IP migration is due to complete in 2027. After a line is migrated, the dial tone that once came directly from the copper network instead comes from equipment that converts the call into data and sends it over the broadband connection.
Why Openreach and BT are closing the network
The PSTN was engineered for analogue voice in an era before the internet existed. The hardware in many exchanges is decades old, the components are increasingly difficult to source, and the engineers trained to maintain it are retiring. Keeping an ageing parallel network running purely for voice, when modern broadband can carry the same calls more reliably and at lower cost, is no longer sustainable. The decision to retire the PSTN was taken by the telecoms industry rather than imposed by government, although Ofcom oversees how the migration is carried out and what protections customers receive.
Moving to internet protocol also brings practical benefits. Digital voice can offer clearer call quality, simpler number management and features that the old network struggled to deliver. The trade-off is that calls now depend on a working broadband connection and mains power, which is why back-up arrangements for vulnerable customers and critical devices have become a central part of the plan.
What replaces the old landline
The replacement for an analogue PSTN line is generally referred to as digital voice or Voice over Internet Protocol, commonly shortened to VoIP. In most homes the telephone handset is plugged into the broadband router rather than directly into the wall socket, and the router converts the call into data. Different providers use different brand names for their digital voice products, but the underlying principle is the same across the market: the call rides on the broadband connection.
For businesses, the equivalent technologies include hosted VoIP and SIP trunking, which connect an existing or cloud-based phone system to the network over the internet. These services can support multiple simultaneous calls, direct dial numbers and call routing without any reliance on copper lines. The key point for both homes and businesses is that the familiar phone number can usually be retained; it is the underlying delivery technology that changes.
PSTN switch-off timeline and key dates
The migration is being delivered in stages rather than as a single overnight event. The table below sets out the broad sequence as published by Openreach and reported through industry communications. Exact local dates depend on the area and the individual provider, so the calendar below describes the published milestones rather than a guaranteed date for any one address.
| Stage | What happens | Who is affected |
|---|---|---|
| Stop sell | New analogue PSTN and ISDN lines are no longer sold in an exchange area | New orders and upgrades |
| Managed migration | Providers move existing customers onto digital voice over broadband | Existing landline customers |
| Vulnerable customer safeguards | Battery back-up and additional checks for telecare and landline-dependent users | At-risk households |
| All-IP completion | Legacy PSTN withdrawn and migration completes | All remaining lines, completing in 2027 |
Who is affected and what to do now
Almost every UK household and business with a landline is affected, but the impact varies. A customer who only uses the phone occasionally for voice calls may notice little beyond a new socket arrangement at the router. The customers who need to act earliest are those who depend on devices connected to the phone line. These include personal alarms and telecare pendants, monitored burglar and fire alarms, fax machines, payment and electronic point of sale terminals, and the emergency telephones inside lifts that must comply with safety standards such as BS EN 81-28.
The single most useful first step is to make a list of everything plugged into the phone line and to contact the relevant communications provider and device suppliers to confirm compatibility. Households that rely on a landline as their only means of contact, or that use a telecare service, should tell their provider so they can be flagged for additional support and a battery back-up unit. Businesses should audit their lines and phone systems well ahead of any local stop-sell date so that replacement services can be arranged without disruption.
Protections for vulnerable and landline-only customers
Ofcom has set out expectations that communications providers must follow to protect customers during the migration. These include identifying customers who may be at risk, such as those who rely solely on a landline or who use a telecare alarm, and providing a solution that keeps them connected during a power cut. A free battery back-up unit is one of the measures available so that an emergency call can still be made if the mains power fails. Providers are also expected to communicate clearly, give reasonable notice and avoid moving anyone before suitable arrangements are in place.
Because providers, not Openreach, hold the direct relationship with the customer, the responsibility for contacting individual households and businesses sits with each communications provider. Anyone who is unsure whether their line has been scheduled for migration should contact their provider directly and ask about the timeline for their area and any support they are entitled to.
Frequently Asked Questions
What is the PSTN switch-off?
The PSTN switch-off is the planned retirement of the UK's copper-based Public Switched Telephone Network. Voice calls that once travelled across the analogue network are being moved to digital voice delivered over a broadband connection using internet protocol. The change affects landline phones and any equipment connected to the phone line.
When is the PSTN being switched off?
Openreach has confirmed that the all-IP migration is due to complete in 2027. The change is happening in stages, with stop-sell of new analogue lines followed by managed migration of existing customers. The exact date for any individual line depends on the local exchange area and the customer's provider.
Will my phone still work after the PSTN switch-off?
Yes, in most cases the same phone number can be kept and an ordinary handset can still be used. The handset is typically plugged into the broadband router rather than the wall socket. Calls then depend on a working broadband connection and mains power, which is why back-up arrangements exist for landline-dependent customers.
Who is responsible for telling me about the switch-off?
The communications provider that supplies the phone or broadband service is responsible for contacting its own customers and arranging the migration. Openreach maintains the underlying network but does not deal with individual customers directly. Anyone unsure of their timeline should contact their provider.
What does Openreach digital voice mean?
Digital voice is the term for a phone service delivered over a broadband connection rather than the legacy copper network. It uses Voice over Internet Protocol to carry calls as data. Different providers brand their digital voice products under different names, but the underlying technology is the same.
