Openreach Warns Businesses as PSTN Switch-Off Nears

Openreach has warned that more than half a million UK business lines remain on legacy copper infrastructure and will face steep price rises as the Public Switched Telephone Network approaches its January 2027 switch-off.

A Century Old Network Reaches Its End

The Public Switched Telephone Network, known as the PSTN, has carried most UK phone calls for more than a century. Built on copper wiring and analogue switching systems, it has supported traditional landlines, fax machines, card terminals, alarm systems and lift emergency lines across the country.

BT Group, Openreach’s parent company, has confirmed that the PSTN will be fully retired by 31 January 2027. As part of that programme, Openreach is withdrawing products that depend on it, including Wholesale Line Rental services used by communications providers to deliver fixed line connectivity to homes and businesses.

In a statement published on its website, Openreach said the PSTN analogue network is obsolete, becoming harder to maintain and significantly more expensive to run. The company has stated that skills and spare parts are increasingly difficult to source, while digital services such as Voice over IP, where calls are transmitted over broadband rather than traditional phone lines, have become the industry standard.

Half A Million Business Lines Still To Migrate

Openreach’s latest figures show that around 2.8 million lines in total remain on the PSTN network, with more than half a million of those serving business premises.

James Lilley, Director of All IP at Openreach, said: “There’s no time left to stall. We’ve spent the last year ensuring telecare customers can be migrated safely through our ‘Prove Telecare’ service, removing the final barrier to the switch-off. Now, the reality is simple. The PSTN analogue network is obsolete, becoming harder to maintain and significantly more expensive to run. We are passing those costs on to providers who continue to sell legacy products.”

He added: “If your business is still on this copper service, you will start to pay a premium for a service that will be switched off in 12 months. Most major Communications Providers moved their customers to digital long ago. If your provider hasn’t contacted you, you need to ask why.”

The switch-off date has been fixed, and Openreach has stated that all technical barriers to migration, including protections for vulnerable telecare users, have now been addressed through its Prove Telecare service.

Price Increases On Legacy Services

Openreach has confirmed a staged series of wholesale price increases for legacy Wholesale Line Rental products during 2026. From 1 April 2026 prices will rise by 20 per cent. From 1 July 2026 they will increase by a further 40 per cent. From 1 October 2026 a final 40 per cent rise will apply, effectively doubling the rental cost of legacy lines compared with 2025 rates.

The wholesale price increases apply to legacy WLR products and are clearly intended to encourage the final migration to digital All IP services. Openreach has also previously confirmed a special pricing offer on migrations to SOGEA, a broadband product that does not require a traditional analogue phone line. In some cases, it is already cheaper to move to newer digital services than remain on older copper-based products.

Openreach has stated that the rising costs reflect the increasing expense of maintaining a shrinking analogue network as the industry moves towards fibre and IP-based connectivity.

Impact Beyond Traditional Phones

The implications extend beyond desk telephones. In fact, the PSTN underpins a wide range of connected systems in commercial and public buildings, and Openreach has highlighted how critical hardware including fire alarms, burglar alarms and payment terminals may still rely on copper lines.

The company’s latest data indicates that more than 12,000 lift lines and around 500 lines serving CCTV networks still require upgrades. Services such as ISDN, ADSL and FTTC broadband are also affected because they depend on the underlying copper infrastructure that supports the PSTN.

Organisations may, therefore, need to review not only voice services but also embedded systems that have operated for years without change.

Role Of Communications Providers

While many major communications providers have already migrated much of their customer base, Openreach has stated that some smaller or specialist providers have been slower to act. Businesses that remain with those providers should note that they may face increased risk as the deadline approaches, particularly if legacy equipment becomes harder to maintain.

Openreach has advised businesses not to assume they are unaffected and to contact their service provider if they are uncertain about their current arrangements.

Review Test Switch Process

Openreach is encouraging businesses to follow a three-stage process of review, test and switch. Businesses should begin by reviewing their connectivity estate to identify any equipment still relying on PSTN services. If there is uncertainty, they are advised to contact their service provider rather than assume migration has already taken place.

Testing can be carried out at Openreach’s test laboratories, where equipment can be checked for compatibility with All IP networks, and the company says that this service is available free of charge to help ensure devices will function correctly once migrated.

Businesses are, therefore, being urged to move to a suitable digital solution as soon as possible, and Openreach says it can offer resources to support the transition, including assistance for more complex or edge case scenarios where temporary solutions may be required.

Resilience And Power Cut Concerns

One of the key challenges associated with the transition relates to power resilience. For example, traditional copper phone lines can be powered from the exchange, meaning they may continue to function during local power cuts. However, digital voice services delivered over broadband require electricity at the customer’s premises. This means that, in the event of a power outage, access to phone services, including emergency calls, could be disrupted unless backup power is available. Communications providers are, therefore, issuing battery backup units to vulnerable customers, typically providing at least one hour of standby power.

This aspect of the transition has drawn some scrutiny from regulators and consumer groups, particularly following severe weather events in recent years that have disrupted power supplies. Industry guidance has emphasised the need to protect vulnerable users during migration to digital services.

Implications

For UK businesses, the remaining 12 months represent a critical planning period. The staged wholesale price increases create a direct financial impact for organisations that delay migration. Companies operating multiple sites or maintaining complex estates may require time to identify dependent systems and coordinate upgrades.

The retirement of the PSTN forms part of a broader national move towards digital, fibre-based connectivity. Openreach has made clear that the January 2027 deadline will not be extended and that the focus is now on completing the final phase of migration away from copper-based services.

What Does This Mean For Your Business?

The timeline is fixed and the cost signals are clear, which means inaction now carries both financial and operational risk. Businesses that fail to identify and migrate remaining copper-dependent services will face rising wholesale charges during 2026 and the possibility of service disruption as the withdrawal progresses. For organisations with critical systems such as alarms, payment infrastructure or lift lines, the issue is not simply about telephony but about continuity, compliance and safety.

For communications providers, particularly smaller or specialist firms, the final year before switch-off will test their ability to complete migrations at pace while maintaining service stability. Delays or poor communication could expose them to reputational damage and customer loss. At the same time, regulators and consumer bodies will continue to scrutinise resilience arrangements, especially around power cuts and protection for vulnerable users.

For UK businesses more broadly, the remaining 12 months represent a narrowing window to audit estates, budget for upgrades and ensure that digital alternatives are fully tested. The retirement of the PSTN marks the end of a long-standing infrastructure platform and the completion of a national move to All IP connectivity. The practical consequences now depend largely on how quickly organisations act to remove their dependence on copper and prepare for a fully digital network environment.