Free online tool
PSTN Switch-Off Checker for Alarm Signalling
Check whether your alarm system may be affected by the UK PSTN switch-off, based on how it signals to the monitoring centre.
About this tool
The SPS Technical PSTN Switch-Off Checker is a free online tool for commercial alarm users. It uses the alarm's signalling type and monitoring arrangement to show whether alarm signals may stop reaching the monitoring centre when the UK's analogue telephone network is switched off, which Openreach plans to complete by January 2027.
Designed for facilities managers, estates teams, responsible persons and business owners. SPS Technical provides commercial fire and security design, installation, maintenance and monitoring across Yorkshire, Lincolnshire and the Humber.
Start PSTN Switch-Off Checker
Answer a few questions about how your alarm signals to get an initial indication of your risk from the PSTN switch-off. This is not a definitive assessment — SPS Technical can confirm your exact position.
110
days
until Openreach's target to finish switching off the UK's analogue telephone network (end of January 2027). Alarms that still signal over a phone line need upgrading before then.
This tool provides an initial indication only. Results are based on the information you have provided and recognised industry standards. They are not a substitute for a site-specific technical assessment, insurer advice or formal compliance review. Maintenance requirements may vary depending on system type, site conditions, monitoring arrangements, certification status and insurer requirements. SPS Technical can confirm the correct requirements following a review of your system.
What the PSTN Switch-Off Means
BT Openreach is replacing the public switched telephone network (PSTN) — the traditional copper telephone network — with an all-IP network. If your alarm system uses a PSTN or telephone line for signalling, it may need to be upgraded to continue communicating reliably with an Alarm Receiving Centre.
The switch-off affects any device that relies on a copper phone line, including monitored alarm signalling paths.
Common Alarm Signalling Types
PSTN / telephone line — most directly affected by the switch-off.
IP / broadband — uses an internet connection; dependent on broadband reliability and power.
4G / cellular — uses a mobile network; generally lower risk for the switch-off.
Dual-path — combines two signalling routes (e.g. IP + 4G) for resilience.
What the Result Does and Does Not Confirm
The result gives an initial, area-based indication of risk based on your postcode and the signalling type you select. It does not confirm the exact line type at your premises, your monitoring path, or whether your system has already been migrated.
Monitored systems require particular attention because a failed signalling path can stop alarm activations reaching an Alarm Receiving Centre. SPS Technical can confirm your actual signalling path — see our alarm monitoring services.
PSTN Switch-Off Checker FAQs
Does the tool tell me my line has been switched off?
No. It gives an initial indication based on your alarm signalling type and monitoring arrangement. The switch-off applies across the whole UK. SPS Technical can confirm your actual line and monitoring path.
I’m not sure what signalling I have — what should I do?
Select “I’m not sure”. The tool will ask for more information, and SPS Technical can identify your signalling path during a review.
Does the switch-off affect fire alarms too?
It can, where a fire alarm uses a PSTN line for monitoring or auto-dial signalling. Monitored fire alarms should be reviewed.
What should I ask my current alarm installer?
Ask how the alarm signals today, whether any part (including a backup path) still uses a copper phone line, whether the equipment works on the all-IP network, what happens if broadband or power fails, and when the signal path was last tested end to end. The checker lists all the questions and puts them in your PDF report.
When is the PSTN switch-off?
Openreach plans to finish switching off the analogue telephone network across the UK by the end of January 2027. Lines are moving over area by area before then, so alarms that rely on a phone line should be upgraded now rather than at the deadline.
What is the fix if my signalling is affected?
Options include upgrading to IP, cellular or dual-path signalling. SPS Technical can advise on the most suitable path for your system and site.
Want a Professional to Verify Your Findings?
Complete the tool above, then request a professional review from SPS Technical. We can confirm the findings on site and explain any remedial options.