UK commercial intruder alarm price ranges in 2026, the EN 50131 grades that drive the cost, and what monitoring and maintenance add on top of the install.
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Quick answer
For a UK commercial intruder alarm in 2026, expect:
- Small commercial (Grade 2, single zone, basic install): £1,500 to £3,000.
- Medium commercial (Grade 2 or 3, multiple zones, dual-path signalling): £3,500 to £8,000.
- Larger or higher security (Grade 3 or 4, full coverage, monitored): £8,000 to £25,000+.
Connected monitoring through an Alarm Receiving Centre adds £300 to £900 per year. Annual maintenance is normally 8 to 15 percent of the install value.
EN 50131 grades, in plain English
UK commercial intruder alarms are graded 1 to 4 under the EN 50131 standard. The grade describes the kind of intruder the system is designed to detect and resist.
Grade 1. Low risk. Domestic-grade equipment. Rare in commercial use.
Grade 2. Low to moderate risk. The most common commercial standard. Designed for intruders with basic tools and knowledge. Suitable for most offices, retail units and small commercial premises.
Grade 3. Higher risk. Designed for intruders with knowledge and a wider range of tools. Required by insurers for higher-value stock, certain industries, or specific building configurations.
Grade 4. High security. Designed for intruders with detailed knowledge and access to advanced equipment. Used in jewellers, banks, museums and specialised high-value commercial premises.
What drives the price
Grade. Higher grades use more sensitive detection, more robust signalling, more thorough commissioning and more thoroughly trained installers. The jump from Grade 2 to Grade 3 typically adds 30 to 60 percent to the install cost.
Number of zones. Each zone is a logical area of the building with its own detection. A single-zone alarm covers one space; a multi-zone alarm covers parts of the building independently so partial-set arming is possible. Most commercial properties end up with three to twelve zones.
Detection device count. PIR detectors, dual-tech detectors, vibration sensors, glass-break sensors, magnetic contacts on doors and windows, beam sensors. The number and type drive both the equipment cost and the installation labour.
Signalling path. Single-path (PSTN, IP, or radio alone) is cheaper but easier to defeat. Dual-path (typically IP plus radio or 4G) is the modern standard and is required by most commercial insurer schedules.
Accreditation. SSAIB accredited installation costs more than non-accredited because the installer carries audited certification, follows documented commissioning processes, and is on insurer and police URN approved lists.
Monitoring cost ranges
Monitoring connects the alarm to an Alarm Receiving Centre (ARC) staffed 24/7. When the alarm activates, the ARC operator verifies the activation and routes the response to the customer's keyholder, the police, or both.
Keyholding only (ARC notifies a keyholder of activations): £200 to £400 per year per system.
Police response with confirmed alarm (URN required): £400 to £900 per year per system, depending on the response category and the ARC.
Live remote video monitoring (operator views CCTV on activation): £600 to £1,500 per year per site.
Maintenance cost
An annual maintenance visit by an SSAIB accredited installer is required by most insurers for the alarm to remain valid. The maintenance contract covers the visit, certificate renewal, faults under warranty, and a defined response time for system-down faults.
Typical commercial maintenance is 8 to 15 percent of the installed value per year. A £5,000 installation typically attracts a £400 to £750 annual maintenance contract.
What you should ask for in a quote
Equipment list. Make and model of the panel, signalling unit and every detector. A single line for "intruder alarm" tells you nothing.
Grade and standard. The EN 50131 grade and any specific insurer schedule the system is designed against.
Signalling. The path (single or dual), the carrier, and the contracted ARC.
Maintenance terms. Service interval, response time, what is covered under contract, what is chargeable.
Accreditation. SSAIB, ISO 9001, manufacturer training. Whether the installer is on the insurer's approved list.
Frequently asked questions
What is a Grade 2 intruder alarm?
Grade 2 under EN 50131 is the most common commercial intruder alarm grade in the UK. It is designed for premises with low to moderate risk, where intruders are expected to have basic knowledge and tools. Most insurers accept Grade 2 for standard commercial properties.
When do I need a Grade 3 alarm?
Grade 3 is required where insurers identify higher risk, typically for premises holding higher-value stock, having a known industry-specific risk (electronics, alcohol, automotive, pharmaceuticals), or where the building's location and layout make Grade 2 inappropriate. Your insurance schedule sets the requirement.
Is monitoring included in the alarm cost?
No. Connection to an Alarm Receiving Centre (ARC) for monitored response is priced separately, typically £300 to £900 per year depending on the alarm grade and the response level. The headline alarm install price covers the equipment and installation only.
Do I need a maintenance contract for an intruder alarm?
Most insurers require an annual maintenance visit by an SSAIB accredited installer for the alarm to remain valid as a security measure. Skipping maintenance is the most common reason an alarm stops being insurer-acceptable.
How is an intruder alarm priced compared to CCTV and access control?
For a typical UK commercial building, the intruder alarm is normally the smallest line on a security quote, with CCTV and access control each costing more for the same site. For a full breakdown of all the systems, see our text-primary hover:underlinecommercial security cost guide.
Get a Hawthorne intruder alarm quote
The ranges above are typical UK market values. For a Hawthorne indicative range based on grade, zones and signalling, use the pricing calculator. For a full quote with a site survey, talk to our team.
About the author
Dr Andrew Threadgold is Co-Owner of Hawthorne. The cost ranges in this article reflect typical UK commercial intruder alarm market values in 2026, compiled from Hawthorne's own quoting experience and industry-published benchmarks.
Last updated: May 2026