The PSTN Switch-Off Explained: Is Your Building Ready?

By January 2027, the UK's Public Switched Telephone Network (PSTN) will be permanently switched off.

For many organisations, that may sound like a telecommunications issue. In reality, it has significant implications for the operation, compliance and resilience of buildings across the UK.

What does this mean for buildings and businesses?

While many organisations have already replaced their phone systems, critical building infrastructure may still rely on the analogue network behind them.

If you're responsible for maintaining a building or estate, understanding where those analogue connections still exist is vital.

Do you know which critical building systems still rely on the analogue network?

Why This Matters

The PSTN switch-off isn't simply about replacing desk telephones.

Many essential building systems still use analogue connections to communicate with monitoring centres, service providers or emergency response teams.

These can include:

• Lift emergency telephones

• Fire alarm monitoring systems

• Intruder alarms

• CCTV monitoring

• Access control systems

• Building Management Systems (BMS)

• Remote monitoring equipment

• Emergency call points

• Telecare and assisted living systems

If these systems haven't been identified and upgraded before the switch-off, organisations could be left with critical building systems that are no longer compliant, no longer operational or unable to perform when they're needed most.

The result is costly disruption, unexpected downtime, increased operational risk and significant remedial costs.

Why the PSTN Switch-Off Matters Beyond Telecommunications

The PSTN switch-off isn't simply a telecommunications upgrade.

Many of the systems that keep buildings safe, secure and operational have historically relied on analogue telephone lines to communicate with monitoring centres, emergency services and service providers.

Fire Safety

Fire alarm monitoring systems may no longer be able to transmit alarm signals to Alarm Receiving Centres (ARCs), potentially delaying emergency response if they haven't been upgraded.

Statutory Compliance

Critical systems relied upon to meet statutory obligations may no longer operate as intended, increasing the risk of non-compliance and exposing organisations to avoidable regulatory issues.

Security

Intruder alarms, CCTV monitoring and access control systems that rely on PSTN connections may lose their ability to communicate with monitoring centres, reducing the effectiveness of site security.

Maintenance

Remote monitoring systems used to detect faults, monitor assets and alert maintenance providers may stop communicating, making proactive maintenance more difficult and increasing reliance on reactive repairs.

Business Continuity

Failures across critical building systems can lead to operational disruption, unplanned downtime and costly interruptions to day-to-day activities.

Asset Management

The transition may expose ageing infrastructure and legacy systems that require upgrading or replacement, creating unexpected capital expenditure and impacting long-term asset planning.

These systems are fundamental to the safe and compliant operation of a building. If they are overlooked during the transition, the consequences can extend far beyond the loss of a telephone line.

Key Questions to Ask Before the PSTN Switch-Off

• Which building systems still rely on analogue telephone lines?

• Have all suppliers confirmed compatibility with digital networks?

• Are any critical safety systems affected?

• Have upgrade works been planned and budgeted?

• Who is responsible for coordinating the transition across our estate?

These questions help move the conversation from telecommunications to operational resilience.

Looking Beyond the Switch-Off

The PSTN switch-off is more than a technology upgrade.

It's an opportunity for organisations to better understand their buildings, review critical infrastructure and strengthen long-term resilience.

Many organisations won't be affected because they've already completed the transition.

Others may discover that important building systems still rely on technology that has quietly remained in place for decades.

For many organisations, the challenge isn't replacing analogue telephone lines. It's identifying the critical building systems that still depend on them.

Understanding those dependencies today can help reduce future disruption, maintain compliance and ensure buildings continue to operate safely and effectively long after the PSTN network has been retired.