What is Gigabit Britain?

The UK is in the middle of one of the biggest telecommunications transformations in its history. The shift, commonly referred to as Gigabit Britain, is about delivering faster, more reliable digital infrastructure to support businesses and households nationwide. For companies of all sizes, this isn’t just about faster downloads – it’s about ensuring continuity, future-proofing operations, and staying competitive in a digital economy.

At the heart of Gigabit Britain are two huge changes: the PSTN switch off and the ISDN switch off, both of which are linked to the wider BT landline switchover. These developments may sound technical, but their impact will be felt by virtually every UK business.

In this blog, we’ll explore what Gigabit Britain really means, why the switch off is happening, and how your business should prepare.

Understanding Gigabit Britain

Gigabit Britain is the UK Government and telecoms industry’s shared ambition to bring gigabit-capable broadband to every corner of the country. The target is for at least 85% of premises to have access to gigabit speeds by 2027, with full nationwide coverage as soon as possible thereafter.

• Gigabit-capable broadband means speeds of 1Gbps (1,000Mbps) or higher.
• This is usually delivered via full-fibre connections, though some hybrid technologies can also achieve gigabit speeds.
• For businesses, it means seamless video conferencing, rapid file transfers, cloud-based applications that run without lag, and robust support for hybrid or remote working.

Gigabit Britain isn’t just about speed – it’s about replacing legacy copper networks with modern fibre infrastructure that’s more reliable, energy-efficient, and ready for the digital future.

Why the PSTN and ISDN Switch Off Matters

The Public Switched Telephone Network (PSTN) and Integrated Services Digital Network (ISDN) are the traditional copper-based systems that have powered UK telephony for decades. However, these technologies are outdated, expensive to maintain, and incompatible with modern digital services.

BT Openreach has confirmed that both the PSTN and ISDN will be switched off by January 2027. This event is often referred to as the BT landline switchover.

Key points:

• After 2027, traditional analogue landlines will no longer work.
• All voice calls will be delivered over IP (internet protocol) using broadband connections.
• Services that rely on copper lines – such as ADSL broadband, alarm systems, fax machines, or payment terminals – may also be affected.

For businesses, this is not optional: if you are still using PSTN or ISDN lines, you will need to migrate to IP-based alternatives before the deadline.

What Services Are Affected by the Switch Off?

The following table outlines which services will be impacted by the PSTN and ISDN switch off, and the recommended alternatives.

The Link Between Gigabit Britain and the BT Landline Switchover

The withdrawal of PSTN and ISDN is more than a cost-saving exercise. It’s part of the UK’s transition to a fully digital network that underpins Gigabit Britain.

By moving all communications onto IP networks:

• Infrastructure is simplified: One modern fibre network can carry voice, data, and video.
• Costs are reduced: Businesses no longer need to maintain separate voice and data connections.
• Flexibility increases: Cloud-based services can be adopted more easily.
• Reliability improves: Fibre is less prone to faults and weather-related issues than copper.

In short, the PSTN and ISDN switch off is a necessary step to make Gigabit Britain a reality.

How Businesses Can Prepare

With the deadline approaching, now is the time to act. Here are some steps every UK business should take:

• Audit your current services: List all the systems connected to your PSTN or ISDN lines. Don’t forget hidden connections like alarms, lift lines, or door entry systems.
• Plan your migration: Decide whether hosted VoIP, SIP trunks, or a full cloud telephony solution is right for your business. Consider how many users you have, what features you need (e.g. call recording, auto attendants), and your budget.
• Upgrade your broadband: A strong broadband connection is essential for voice over IP. Ensure your line has enough bandwidth and reliability. A dedicated leased line or fibre broadband is often the best choice for businesses.
• Test compatibility: Check whether any legacy systems will continue to work once migrated. If not, plan replacements ahead of time.
• Choose a trusted partner: Working with an experienced provider ensures the transition is smooth. At Leasedline.co.uk, we partner with top UK suppliers to deliver business-grade Ethernet, broadband and VoIP solutions designed to handle the demands of modern organisations.

What is “Fit to Switch”?

As part of the BT landline switchover, Openreach has introduced the Fit to Switch campaign. This initiative is designed to raise awareness and ensure that all organisations – especially small and medium-sized businesses – are ready for the PSTN and ISDN switch off.

Being “Fit to Switch” means your business has assessed its current telephony and connectivity setup, identified any systems that depend on analogue lines (such as phones, alarms, lift lines or payment machines), and taken the necessary steps to migrate to digital alternatives. It’s not just about replacing your landline; it’s about making sure your entire infrastructure is prepared for an all-IP future.

For businesses, engaging with the Fit to Switch programme early can prevent last-minute disruption and give you time to explore options like VoIP, SIP trunks, or full fibre broadband – all of which are key enablers of Gigabit Britain.

Why Gigabit Britain is Good News for Small Businesses

Although the switch off may feel disruptive, it also presents opportunities. Small businesses, in particular, stand to benefit from Gigabit Britain:

• Faster, more reliable broadband enables better customer service and productivity.
• VoIP and hosted telephony can reduce costs while providing enterprise-grade features like call routing and conferencing.
• Future-proofing ensures businesses won’t be left behind as technology evolves.
• Improved collaboration with cloud applications, video conferencing, and file sharing that work seamlessly on faster connections.

Key Dates to Remember

• Now: Stop Sell in many areas – no new PSTN or ISDN lines are being installed.
• 2023-2026: Gradual withdrawal continues, with migration encouraged.
• January 2027: Final switch off – all PSTN and ISDN services cease.

Businesses that wait until the last minute risk disruption, downtime, or rushed migrations. Early planning avoids these risks.

Final Thoughts

Gigabit Britain represents a turning point for the UK’s digital economy. The PSTN switch off, ISDN switch off, and the wider BT landline switchover are essential steps towards delivering the fibre-based, gigabit-capable infrastructure that businesses need to thrive.

Rather than viewing this as an inconvenience, forward-thinking businesses should see it as an opportunity: to modernise communications, cut costs, and unlock new ways of working.

At Leasedline.co.uk, we’re here to support your transition to Gigabit Britain. From upgrading your broadband to deploying VoIP solutions, we’ll ensure your business is fully prepared for a digital-first future.

If you want to find out more about preparing your business for the big switch over, get in touch with one of our experts today.