Established in Hull in 1992 — Fire & Security Systems Across Yorkshire, Lincolnshire & the Humber

01482 226570|Contact
Alarm signalling upgrade from analogue phone lines
PSTN switch-off

PSTN Switch-Off: Is Your Intruder Alarm Still Monitoring?

Analogue telephone lines are being switched off across the UK. Alarms that still signal over them can lose their monitoring connection, and with it their police response.

Openreach's analogue PSTN telephone network is being switched off across the UK — and any intruder alarm using a phone line to signal an Alarm Receiving Centre is at risk of losing its monitoring path. Over 51% of UK exchanges have already stopped new PSTN connections. When the line goes, the alarm still sounds locally, but no signal reaches the ARC, no keyholder is contacted and no police response is dispatched. Many businesses don't realise their monitoring has been affected until after an incident. SPS Technical audits existing signalling paths and migrates systems to IP or 4G dual-path signalling across Yorkshire, Lincolnshire and the Humber.

The problem

Openreach's switch-off of the analogue PSTN telephone network is already underway, with over 51% of UK exchanges now stopped for new PSTN connections. When the line goes, any intruder alarm using it to signal an Alarm Receiving Centre loses its monitoring path. The alarm still sounds locally — but no signal reaches the ARC, no keyholder is contacted, and no police response is dispatched. Many businesses don't know their signalling path has been affected until after an incident.

What Happens When Your PSTN Signalling Path Fails

The PSTN switch-off is not a sudden event — it happens exchange by exchange, and many businesses only discover their monitoring has been affected when something goes wrong. The sequence of consequences is predictable and serious.

The PSTN switch-off

Is your alarm still monitoring?

Openreach's analogue telephone network switch-off is already underway. Any intruder alarm using a phone line to signal an Alarm Receiving Centre follows this path.

01
PSTN line disconnected by Openreach
02
Alarm signal path fails silently
03
ARC receives no signal on activation
04
No keyholder contacted
05
No police response dispatched
51%+
UK exchanges already on stop-sell
2027
Full PSTN switch-off deadline
IP/4G
Dual-path replacement standard
SPS Technical audits existing signalling paths and migrates systems to IP or 4G dual-path signalling — maintaining police response and ARC compliance throughout the migration.

Risk indicators

How to Tell If Your System Is at Risk

If your intruder alarm uses a BT or analogue telephone line to contact your monitoring centre, or if your alarm panel has a built-in dialler rather than an IP or 4G communicator, your signalling path is at risk. SPS Technical can audit your existing setup and confirm whether a migration is needed.

Your intruder alarm uses a BT or analogue phone line to contact the monitoring centre
Your alarm panel has a built-in dialler rather than an IP or 4G communicator
Your maintenance contract hasn't been reviewed for signalling compliance recently
You've recently had phone line issues and your monitoring centre didn't alert you
Your premises are in one of the 51%+ of exchanges already on the stop-sell list

The solution

How the Migration Works

In most cases, migration to IP or 4G dual-path signalling does not require replacing the entire alarm system. A new communicator is fitted to the existing panel, tested and registered with the ARC. The process is straightforward and causes minimal disruption to your monitoring coverage during the transition.

1

Signalling audit

We identify your current transmission path and check exchange status

2

Communicator selection

IP, 4G or dual-path communicator specified to EN50136

3

Installation

New communicator fitted to existing panel in most cases — no full system replacement needed

4

ARC reconnection

Monitoring restored and dual-path signalling confirmed

5

Compliance verification

EN50136 certificate issued, police URN status confirmed

1

Signalling audit

We identify your current transmission path and check exchange status

2

Communicator selection

IP, 4G or dual-path communicator specified to EN50136

3

Installation

New communicator fitted to existing panel in most cases — no full system replacement needed

4

ARC reconnection

Monitoring restored and dual-path signalling confirmed

5

Compliance verification

EN50136 certificate issued, police URN status confirmed

No full system replacement in most cases
ARC monitoring maintained throughout
EN50136 compliant on completion
Police URN status preserved
Free Tool

PSTN Switch-Off Risk Checker

Enter your postcode and current signalling type to get an initial indication of your alarm signalling risk from the PSTN switch-off. No account needed — results in under 2 minutes.

Takes 2 minutes — no account needed. Results are indicative only.

Standards that apply

The standards behind alarm signalling

The British Standards and laws we work to, in plain English. Each one links to a summary page with the current edition and the official source.

Got a question about alarm signalling?

Ask the Standards Library. Answers come only from our library and quote their sources.

Full resource library →

Try one of these:

Answers come only from our standards library and quote their sources. They are general guidance, not advice for a specific building, and are produced automatically, so check the source before relying on them. Please don't include names or personal details in your question.

Editions checked 12 October 2026 by the SPS Technical team.

FAQs

PSTN switch-off questions

If your alarm signals over an analogue phone line, yes. Analogue lines are being switched off, so the signalling needs moving to a digital or dual-path IP service. Our free PSTN Checker tells you where you stand.

A Unique Reference Number issued by the police to an alarm that meets their requirements. It lets the monitoring centre request police attendance when the alarm is confirmed. We apply for and manage URNs for our customers.

Request a signalling audit

We'll check your current signalling path and advise on the migration options available.

Accreditations

Why trust SPS Technical

Independently certified, working to British Standards. Check every accreditation on the official register.

SSAIB

Registration HUMB018

Intruder alarms to PD 6662, CCTV to SSAIB Code of Practice SS2003, access control to SS2002, and fire alarm systems

Verify at ssaib.org

BAFE SP203-1

Certificate 104302 · Organisation ID 303286

Fire alarm design, installation, commissioning and maintenance to BS 5839-1

Verify at bafe.org.uk

ISO 9001 and ISO 14001

1208-QMS-001 · 1208-EMS-001

Quality and environmental management, certified by Alcumus ISOQAR. ISO 9001 held since 1997

Safety and procurement

CHAS-0004703 · Constructionline 92018 · SafeContractor PE5040

SSIP health and safety approval, procurement registration and Paxton Gold Installer status

Police-response intruder alarms

For intruder alarms, SPS Technical is an approved installer of police-response systems with the following forces, so your intruder alarm can be issued a police Unique Reference Number (URN) under the NPCC Police Requirements for Security Systems.

  • Humberside Police
  • Lincolnshire Police
  • North Yorkshire Police
  • South Yorkshire Police
  • West Yorkshire Police
  • Nottinghamshire Police
  • Derbyshire Constabulary
  • Greater Manchester Police

Police approval applies to intruder alarms only.

Since 1992

Established in Hull

1,750+

Systems maintained

2,850+

Scheduled service visits a year

4

Regional offices: Hull, Grimsby, Lincoln, Sheffield

Trusted across universities, NHS and healthcare, local authorities, schools and academy trusts, logistics and industrial sites, transport, and stadiums and venues.

Reviewed by the SPS Technical team · Last updated October 2026

Full accreditation details