Beyond the Phone: Devices That Rely on Your Landline

When businesses think about the phone switch-off, they picture handsets. But the analogue line often quietly powers far more - alarms, lifts, card terminals, fax machines and door entry systems. These can be the riskiest part of the migration precisely because they're forgotten. Here's what to check.

Why this matters

The PSTN switch-off (completing 31 January 2027) retires the analogue network entirely. Anything that dials out or signals over a copper line is in scope - not just phones. Because these devices are easy to overlook and some are safety-critical, they deserve their own line in your plan. Our switch-off checklist makes sure they're not missed.

The usual suspects

Alarm and security systems

Many intruder and fire alarms signal to a monitoring centre over the phone line. After the switch-off they need an alternative signalling path - often a digital or mobile-based solution. Speak to your alarm provider early; don't assume it'll keep working.

Lift emergency lines

A lift's emergency phone is safety-critical and legally required to work, including during a power cut. These cannot simply move to office broadband - they need a dedicated, resilient solution (commonly a mobile/GSM-based line with battery backup). Treat this as a priority and involve your lift maintenance company.

Card payment terminals

Older card machines that dial out over a phone line need replacing or moving to an internet/mobile connection. Most modern terminals already use broadband or mobile data, so this is often a straightforward upgrade - but check before the line goes.

Fax machines

Fax over the analogue line will stop working. Options include a digital fax service (fax-to-email), moving the function online, or retiring fax altogether - many businesses find they no longer need it.

Door entry and gate intercoms

Intercoms that call out over a phone line need migrating to a digital or mobile-based equivalent. Check with the manufacturer or installer.

Other dial-out equipment

Anything else that "phones home" - some CCTV, EPOS, monitoring and telemetry kit - should be on your audit list too.

Why these need power and resilience planning

Unlike a forgotten back-office handset, many of these devices are critical and were designed around the copper line's quirks - including the fact it carried its own power. Their replacements usually depend on mains power and a connection, so resilience matters. We cover battery backup and failover in landline resilience and failover.

How to handle the migration

1. Walk the building and list everything connected to a phone line - not just phones.
2. Identify the critical ones (alarms, lifts) and prioritise them.
3. Contact each device's provider/installer - they'll know the right replacement.
4. Plan resilience for anything safety-critical or business-critical.
5. Migrate and test before the old line is ceased.

Fold this into your overall move using the analogue line replacement guide.

The bottom line

The switch-off is about far more than handsets. Alarms, lifts, card machines, fax and door entry can all depend on the analogue line - and some are safety-critical. Audit everything early, involve the right specialists, and plan resilience, so nothing important goes dark. Want help auditing your site? Explore our Cloud Telephony service or request a callback.