The PSTN Switch-Off – Your springboard to the Connected Cloud

In December 2025, Openreach will deactivate the public switched telephone network (PSTN), which underpins integrated services digital network (ISDN), Asymmetric Digital Subscriber Line (ASDL), and Fibre to the Cabinet (FTTC) services. As a result, these services – and the services that are built on top of them – will go offline. The good news is there’s no need to panic. Plenty of alternative solutions exist which offer businesses the ability to modernise their environment.

The big switch-off is coming into view

PSTN has been the backbone of the UK’s communications infrastructure since it was first developed in the late 19^th century, and, as one might expect, it’s overdue for modernisation – the last 2 years have seen a 27% increase in incidents with the network, and the underlying technology is fast approaching end-of-life.

Although many businesses still leverage services running on this technology, its age and the subsequent performance and capacity limitations mean that it is poorly placed to support the latest innovations, leaving users at a disadvantage. PSTN wasn’t developed for a world where high-speed broadband is the norm, and the underlying technology can’t keep up with an ever-increasing demand for bandwidth driven by newer developments like video streaming, cloud applications, and unified communications.

As such, businesses that get ahead of the game by taking proactive action to replace outgoing legacy infrastructure with an innovative and future-ready alternative will be best placed to unlock long-term benefits. While the switch-off may seem like a significant transition, it is perhaps best viewed as part of the ongoing transformation across your business and a positive opportunity to level up a key area of the infrastructure as part of your complete connected cloud solution. The most crucial step in this journey is identifying a solution that aligns with your strategy, which can only be achieved when you know the full impact on your current services.

The impact on business telephony

Telephony is a significant concern for many organisations moving on from PSTN who may rely on traditional wired phone systems to support their day-to-day communications.

Ahead of the 2025 deadline, businesses using PSTN-based solutions will need to have migrated to an alternative, all-IP solution to ensure the continuation of their service. The good news is that there are plenty of options available, many of which represent a near like-for-like replacement that can be easily deployed. Of these options, the outstanding candidate for many is Voice over Internet Protocol (VoIP).

As the name suggests, VoIP runs voice communications through the internet, allowing businesses to make use of fibre connections, rather than the copper wiring that the core of PSTN. This has a lot of advantages – for businesses already using more advanced solutions like Fibre to the Premises (FTTP) for their internet and data infrastructure, moving over to VoIP allows everything to be brought into a single infrastructure, rationalising costs and simplifying management.

VoIP solutions also offer superior service availability, and more powerful connections help to improve the quality of calls, modernising the voice component of your business operations. These solutions often work within the channels your business is already making use of. Our digital voice line services work as a direct replacement for outgoing PSTN infrastructure, keeping the same feel of existing voice services, but with the benefits of a modern digital infrastructure. Hosted solutions like 8x8 build even further on the capabilities of VoIP, integrating into solutions like Microsoft Teams to bring new voice capabilities into the workflows your users are already familiar with.

Since these are delivered over the internet, rather than using physical, geographically static phone lines, users can take and receive calls to their business phone on the go, as well as at their desk, by using dedicated apps on laptops and mobile devices.

It’s not just voice that you need to consider

Although much of the noise in the market to date has centred on voice, this isn’t the only part of your infrastructure that may require an upgrade. Ancillary systems, such as alarms and CCTV which run on PSTN and ISDN, will be affected. Your broadband services are also an area that needs some consideration. Legacy solutions, such as Asymmetric Digital Subscriber Line (ADSL) and Fibre to the Cabinet (FTTC) will be phased out as part of the switch-off, so businesses leveraging these services will be faced with an opportunity to refresh, enhance and extend their capabilities with an alternative solution.

While internet- and cloud-based voice solutions offer more like-for-like alternatives for voice, replacing data infrastructure can be a bit more nuanced. In most cases, the best solution is either FTTP, or a mobile broadband network built on 4G or 5G. While FTTC runs fibre close to the end location, and connects the final length via PTSN, FTTP runs fibre directly to the premises, delivering significantly faster speeds – up to 1 Gbit/s- and more reliable service. Similarly, 4G & 5G mobile broadband solutions can offer performance and reliability in areas where fibre service would be cost-prohibitive, or otherwise infeasible.

There are also more niche solutions for different scenarios – SoGEA (single order generic ethernet access) uses existing FTTC connections, but operates independently from PSTN, making it a useful intermediate solution in instances where a full FTTP connection isn’t yet available.

Starlink low Earth orbit (LEO) satellites is another option for modernising data infrastructures, albeit one that is best suited to specific use cases. Rather than traditional fixed lines, Starlink makes use of a network of satellites to deliver high-speed, reliable internet access, which is especially useful for locations where more traditional data infrastructures would be impractical or impossible to deploy.

No matter what broadband services you decide to upgrade to, the benefits are clear. Modern IT environments demand greater connectivity than ever before – whether that’s improved service reliability, wider internet access to support IoT networks, or faster connection speeds to support a cloud-first approach to day-to-day operations.

In the same way that the developers of PSTN couldn’t have predicted how the network would be used 100 years in the future, it’s hard to predict what IT environments will look like in the far future, but we’re certain that more modernised data infrastructures will be key to unlocking their potential.

How can you get started?

While moving away from PSTN will be an inevitability for every business that hasn’t already, there’s huge potential for new solutions to meet the precise needs of your organisation, and add value to your IT environment. September 2023 marks the stop-sell date for all PSTN-based services, including analogue voice, ISDN, ADSL, and FTTC, so it’s important to start considering your steps to modernisation now.

With our expertise, we can take a comprehensive view of your environment, and work with you to find the best solutions – not just finding a replacement for voice and data infrastructures, but helping you build upon them and create a network that enables growth across the areas that are critical to your business.

Get in touch with us today to set up an initial discovery session to help you better understand how the PSTN switch-off will affect your business, and find the best replacement solutions to help you stay ahead of the curve.