Is your business ready for the great PSTN switch-off?

Written by Tom Montague – Sales Director. 

Between now and January 2027, the UK's public switched telephone network (PSTN) is gradually being shut down. 

While the move was delayed last year, with the final date slipping from December 2025, customers will over the next two years be migrated to new digital technology using an internet connection, such as Voice over Internet Protocol (VoIP), Digital Voice, or All-IP telephony.

Legacy systems supported by the PSTN – including WLR, IDSN 2 and IDSN 30 – will stop working, as will Asymmetrical Digital Subscriber Lines (ADSL) broadband and Fibre to the Cabinet (FTTC).

Already, businesses are no longer able to buy traditional landline contracts or PSTN-enabled devices such as legacy phones or fax machines.

Digital rollout underway

And the rollout has already started, with the North West and London switching to Digital Voice late last year, and the West Midlands, South East, Wales, and East Anglia all set to follow suit during the spring. The North East, Scotland, and the South West will be migrated over the summer.

The change is needed because underground copper wires are no longer up to the job – a recent report from Ofcom, for example, found that the number of significant PSTN resilience incidents reported increased sharply by 45 per cent last year. 

There was a 20 per cent increase in faults on the Openreach copper network during 2023, and a 60 per cent increase in hours lost for customers using the PSTN.

The advantages of IP

With IP technology, users will be able to make and take calls on any device, on the same number, and will be able to link business applications and systems to video chat, calls and other types of collaboration. The change should also bring greater network stability, security, and efficiency.

Voice over IP is cheaper and faster than ISDN, and provides much higher cloud networking speeds, along with enhanced security. 

A similar switch-over has already taken place in Estonia and the Netherlands, while Germany, Japan, and Sweden are all in the process of making the shift.

But while the move has been signalled since 2015, it seems that many UK businesses aren't ready for the change.

A report late last year from Zen Internet found that only 18 per cent of small businesses and a quarter of large firms had a post-PSTN solution in place. 

While a fifth said they were currently migrating to another system, more than a quarter were still assessing their options, and 17 per cent said they hadn't yet worked out what their next steps would be. Most worryingly of all, nearly one in ten was completely unaware of the coming change.

"Too many businesses may be leaving decisions around all-IP communications to the last minute, which could be a recipe for disruption," said Zen strategy director David Barber.

There are alternatives to the new digital service – most notably the use of leased lines, and  full-fibre broadband lines that are dedicated to a specific location.

How to prepare

However, the vast majority of businesses will need to make the switch, and BT is urging them to get ahead of the game by doing this as soon as possible – at least by the end of this year. 

And they should start auditing systems now, advises cloud, communications, and document solutions supplier Espria. This means not only looking at voice services, video conferencing, and real-time collaboration tools, but also at humbler but still-vital systems, such as alarms, door entry systems, lift emergency lines, payment terminals, cash, and fax machines.

"Businesses have a duty to themselves to ensure they do not lose access to vital communications tools, and that means looking into exactly what systems are at risk of disrupted business continuity," advises Andy Fung, communications solutions architect at Espria. 

"The switch off not only affects your telecommunications but could also disrupt your alarm systems, PDQ and EPOS machines, lifts, and more, interrupting more than just your business communications." 

BT advises assigning clear leadership to the switch-over project, bringing together both organisational and technology perspectives. Any potential pitfalls should be identified and strategies developed for dealing with them, and a roadmap for action should be communicated regularly to the wider organisation. And as part of this, businesses should consider how home- and hybrid-workers will be affected.

Quite the task – but, says Barber, "Transitioning to all-IP not only ensures continuity but opens new opportunities for enhanced features and flexibility in communications." 

In summary, the transition from the UK's PSTN to digital technology is a significant change that businesses must prepare for to avoid disruptions. The shift to IP technology offers numerous benefits, including improved network stability, security, and efficiency. However, many businesses are still unprepared for this transition.