Is Your Business Ready for the PSTN Switch-Off?

If you think this won’t affect you, think again. By the end of next year, every traditional landline phone, ISDN system and copper-based communication service in the UK will be switched off for good. This isn’t just a quiet upgrade. It’s a full infrastructure retirement and it’s coming fast.

That means every business still using these systems, knowingly or not, is standing on borrowed time. This includes more than just desk phones. Alarm lines, card machines, fax services, lift emergency phones, even door access systems could all go dark if you haven’t moved to an IP-based setup.

The scary part? Many businesses don’t even know what services they still have running through the old network. They won’t notice until it’s too late. That’s why you need to act now. This article will give you everything you need to know to prepare, avoid costly disruption, and unlock real benefits in the process. Because this isn’t just a shutdown. It’s an opportunity to improve how your business communicates, operates and grows.

BT Openreach has now confirmed the complete switch-off will happen by January 2027, and many regions are already seeing a "stop-sell" in effect. That means no new lines, no upgrades, and very soon, no service at all. You can read more about Openreach’s official withdrawal plan and how this is already underway.

Your traditional phone line will not function after that date. Any system still depending on it - voice calls, fax machines, alarm panels and lift links will all fail unless migrated to a digital alternative. This is not a temporary interruption. It’s permanent infrastructure retirement.

Why Businesses Can’t Afford to Delay

This isn't a technical issue for your IT team to quietly handle in the background. This is a business-wide risk. When the deadline hits, your ability to operate, take payments, answer calls, run security and reach customers could all be compromised.

A 2024 report by Ofcom highlighted that millions of lines are still active across businesses, with thousands unaware they are using legacy systems. We've already seen cases where businesses had their payment terminals or alarm systems suddenly stop working, not realising they still depended on PSTN lines hidden in the walls.

When your phone lines go down, even for one day, that could mean lost deals, frustrated customers, missed opportunities and serious safety risks. If you're in healthcare, education or professional services, the stakes are even higher. Delaying this transition is not just risky, it’s potentially reckless.

What Gets Affected: It's More Than Just Your Phones

While most people associate PSTN with desk phones, it actually powers a surprising range of critical systems. These include:

• Fire and burglar alarms connected to monitoring centres

• Card machines that run through analogue lines

• Fax and franking machines used for legal or financial documentation

• Door entry systems and lift emergency call buttons

• Older broadband connections (ADSL) that piggyback on copper lines

If any of those are in use across your organisation, you’ll need to upgrade or replace them. And in many cases, you’ll need to do so with enough lead time to test, train, and validate that they function fully before the cutoff.

What You Need Instead: Switching to All-IP

The entire telecoms network is moving to an All-IP environment, meaning all communications will run over the internet rather than through analogue signals. For voice, that means switching to VoIP (Voice over Internet Protocol). For devices, it means updating to digital-compatible models or rerouting through 4G, fibre or cloud-based systems.

VoIP isn't just a replacement. It's an upgrade in almost every way. You get features like mobile handsets, call recording, CRM integration, video conferencing, and remote access, all at a lower cost than legacy ISDN lines. SIP trunks offer scalability and resilience, especially for larger businesses transitioning from ISDN30.

If you're still unsure how VoIP actually performs in practice, read how VoIP systems help businesses reduce cost and improve flexibility.

Real Benefits of Moving Early

Here’s what businesses gain when they stop clinging to old infrastructure:

• Lower call costs: VoIP and SIP lines are dramatically cheaper than ISDN

• Flexible working: Employees can take calls anywhere with mobile apps or softphones

• Scalability: Add or remove users without needing engineer visits or phone rewiring

• Resilience: Cloud-based systems can route calls even during outages or office moves

• Integration: Combine phones with CRM, support tickets and call analytics

For example, a retail chain with 15 branches in the South East migrated to VoIP and slashed their telecom bill by 42%, while also enabling staff to handle calls remotely during store closures. They also replaced alarm panels with IP-compatible units that allow remote monitoring.

You’re not just avoiding a shutdown. You’re gaining flexibility, performance and long-term savings.

The Hidden Costs of Waiting

Businesses often fall into the trap of thinking this isn’t urgent. But every day you delay brings new problems.

As the shutdown nears, installation queues grow longer, providers become oversubscribed, and prices often rise due to demand. Some areas are already in stop-sell zones, meaning you can't even request changes to existing PSTN or ISDN services. You can check your area's status using Openreach's rollout map.

We’ve already seen examples where companies have waited too long and been left scrambling for emergency replacements when lines failed. That can mean rush fees, system downtime and reputational damage.

Planning your transition early allows time to research, test, and train your staff properly. And that’s how you avoid chaos.

Step-by-Step: How to Prepare Your Business

The process doesn’t have to be complicated, but it does require a proper plan. Here’s what to do:

1. Audit every location and device - Check what systems are still using PSTN or ISDN, including phones, alarms, lifts, payment machines and fax lines.

2. Speak to your current provider - Some may offer partial upgrades that still rely on copper. Make sure you're moving to full IP-based replacements.

3. Evaluate your connectivity - VoIP depends on stable internet. If you're using ADSL or copper-based broadband, now is the time to upgrade to fibre.

4. Choose the right VoIP solution - Whether it’s hosted VoIP, SIP trunks or a hybrid model, the system should suit your team’s needs, locations and call volumes.

5. Replace outdated endpoints - Devices like alarm systems and fax machines may need modern, IP-enabled replacements. Speak to your vendor early.

6. Test, train and launch - Ensure your staff are confident and all systems work before the PSTN gets shut down.

This guide from Ofcom’s digital switchover recommendations can help you structure your internal rollout plan properly.

Don’t Just Avoid a Crisis - Use This to Upgrade

The PSTN switch-off isn’t just an inconvenience. It’s a turning point. Smart businesses aren’t just looking to survive the change, they’re using it to build more agile, future-proof systems.

By moving to VoIP and cloud-hosted communications, you position your business for a hybrid workforce, scale up without hassle, and reduce telecom costs by thousands annually. It’s not about compliance. It’s about staying competitive.