Burglar alarm costs: monitored vs bells-only, and what you actually get

Choosing a burglar alarm means choosing between two genuinely different products, not just two price points, and understanding what each option actually gives you matters more than the headline cost. A bells-only alarm sounds a loud siren when triggered but doesn't notify anyone beyond whoever's in earshot — no monitoring centre, no automatic police involvement. A professionally monitored alarm, by contrast, sends an alert to a staffed Alarm Receiving Centre (ARC) when triggered, and depending on the tier chosen, that alert can lead to a phone call to check in, a keyholder being contacted, or in some cases a request for police attendance.

On price, a professionally installed bells-only alarm typically costs around £500-£800 to fit, with no ongoing monitoring fee since there's nothing being monitored. A professionally monitored alarm typically costs around £750-£1,300 to install, plus roughly £15-£40 a month in monitoring fees depending on the provider and the level of service. A smart alarm with integrated CCTV, increasingly common as the two systems converge, commonly runs £1,200-£2,500 or more once cameras, sensors and monitoring are all bundled together. Monitoring itself comes in tiers: self-monitoring, where alerts simply go to your own phone with little or no monthly fee, sits at the bottom; professional ARC monitoring, commonly cited around £15-£25 a month, sits in the middle; and a police-response tier, commonly cited somewhere around £8-£40 a month depending on provider and exactly what's included, sits at the top.

The police-response tier is where a Unique Reference Number, or URN, comes in, and it's worth understanding exactly what it does and doesn't guarantee. A URN is issued under the National Police Chiefs' Council's (NPCC, the body that succeeded the older ACPO) security systems policy, and it's the mechanism that allows a police force to treat a confirmed alarm activation as worth a physical response rather than simply a false alarm to log. Critically, a URN can only be issued where the alarm is professionally monitored through an ARC and was installed by a company certified by NSI or SSAIB — the two main UK third-party certification bodies for the security industry — so a bells-only alarm, a self-monitored DIY kit, or a system installed by an uncertified company simply isn't eligible for one, regardless of how good the equipment is. Even with a URN in place, police response is never guaranteed on any individual call-out, and a URN can be withdrawn if a system generates repeated false alarms, which is one of the reasons a badly calibrated or poorly maintained system can end up costing more in the long run than it saves.

Insurance is the other major reason monitoring tier matters beyond personal preference. Many standard home insurance policies don't require any particular alarm specification at all, but commercial policies and higher-risk home policies — a high-value property, a rural property, or one with a previous claims history — commonly require the alarm to be installed, and sometimes monitored, by an NSI- or SSAIB-approved company as a specific policy condition. Where that condition applies, choosing an uncertified installer purely on price can end up invalidating cover entirely if a claim is ever made, which makes checking accreditation before booking work considerably more important than it might first appear for a fairly ordinary-looking purchase.

Deciding between bells-only and monitored ultimately comes down to what you're trying to achieve. A bells-only alarm is a genuinely effective deterrent for many ordinary homes — the noise alone disrupts most opportunist break-ins and alerts neighbours — at a noticeably lower upfront cost and with no ongoing fee. Monitored systems suit situations where an unattended response matters more: a second home, a commercial premises with valuable stock, a property that's often empty during the day, or simply a household that wants the reassurance of a monitoring centre and the possibility of a police response rather than relying on someone happening to hear the siren and act on it. For anyone leaning towards a monitored system with genuine police-response eligibility, checking that a prospective installer is NSI or SSAIB certified before getting a quote is the single most useful filter, since it rules out installers who couldn't deliver a URN-eligible system even if asked to.

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