The PSTN switch-off enters its final year – what this means for your business in 2026

The national move away from the old Public Switched Telephone Network (PSTN) is entering its final year. Openreach has confirmed that the switch-off will go ahead in January 2027 and will not be delayed. That means any services still running on older technologies like WLR or ISDN need to move to modern all-IP alternatives before next January’s deadline.

To help you prepare, we’re sharing this early heads-up. These changes affect every provider across the industry and are happening nationally, not just at Zen. If your business still uses services on the PSTN network, such as WLR or ISDN, you’ll receive formal notice soon.

Our teams are ready to support you with the move as soon as you’re ready to start planning. Acting now means you can avoid rising costs and prevent last-minute disruption.

A quick reminder: what are WLR and ISDN?

These are the traditional copper-based phone services many businesses have used for years. They support standard voice calls and a range of equipment from alarms and lift lines to payment terminals. As the UK moves to a fully digital network, these older technologies are being retired.

What’s changing in 2026?

Openreach has announced a series of industry-wide price increases for any remaining WLR and ISDN services. These uplifts are cumulative across the year (figures calculated against December 2025 pricing):

• April 2026: +20%
• July 2026: +60%
• December 2026: Final increase bringing the total to 100%

These increases apply to every communications provider. They reflect the cost of maintaining the legacy network during its final year - as well as incentivising users to move from legacy technology as soon as possible. Moving to an all-IP alternative removes the impact entirely.

What happens if you do nothing?

Any services still on WLR or ISDN at the January 2027 switch-off will be moved by Openreach to a basic fallback called Emergency Voice Access (EVAC).

EVAC is designed for emergency voice calls only and won’t support the services businesses rely on today. That includes:

• Broadband
• Alarm lines
• Lift lines
• Card machines and payment terminals
• Telemetry and monitoring systems

It also provides fewer features than current PSTN services. It’s a safety net, not a long-term solution, so relying on it could lead to significant avoidable disruption.

What you should do next

Most migrations are straightforward when planned early. To get started:

1. Review any remaining PSTN-based services in your business, including voice lines, alarms, lifts and payment devices.
2. Speak to the suppliers of alarms or specialist equipment to check what digital alternatives they offer.
3. Contact your Zen account manager to plan your move and choose the right IP-based alternative. If you don’t have an account manager, contact us here.

Why acting now is the sensible decision

Upgrading now gives you time to choose the right option, avoid unnecessary cost increases and make a smooth transition. Moving to digital services brings a range of benefits:

Cost avoidance

By switching sooner, you avoid the steep and compounding price rises scheduled for 2026.

A futureproof move

The UK’s network is going all-IP. Upgrading now means a single, clean transition instead of multiple enforced changes in the near future.

Better reliability and performance

Modern digital voice services offer clearer audio, fewer faults and a much more resilient service.

Smarter features for modern working

Digital alternatives support the way businesses work today, with options such as:

• CloudComms
• Digital Voice
• SIP Trunking
• FTTP, SoGEA and other all-IP connectivity

Stronger security and compliance

Digital platforms offer up-to-date security standards and reduce the risks tied to end-of-life copper infrastructure.

Better for the environment

All-IP services use less power and help reduce reliance on older, carbon-intensive infrastructure.

We’re here to support you through the transition and make sure everything goes smoothly. If you still rely on PSTN-based services, now is the time to start planning your next steps.