Do burglar alarms actually deter burglars? What the evidence says
By the team behind the Home Alarm Checker. Updated 26 August 2026.
The home-security industry has an awkward secret: its most heavily marketed product — the monitored burglar alarm with a monthly fee — is the one with the weakest evidence behind it. The cheap, boring stuff works better. That's not a contrarian pose; it's what the UK's own crime data says, and it's worth £2,000+ to you over five years, so let's go through it properly.
First, calibration. Burglary is rarer than the adverts imply: the Crime Survey recorded 327,000 domestic burglaries in the year ending December 2025, down 22% year on year, and households are roughly 4x less likely to be burgled than in 1995 (checked Aug 2026). About 70% of entries are through a door, and around three-fifths happen between 6pm and 6am. The ONS itself credits improved home security for much of the long fall — so security spending isn't pointless. The question is which £300 does the work.
The research the alarm industry never quotes
The best UK evidence is the Crime Survey security-device analysis led by Prof. Andromachi Tseloni (Tseloni, Thompson, Grove, Tilley & Farrell, Security Journal, 2017). It computes protection factors for every device combination in thousands of real burglaries. Individually, external lights and double/deadlocked doors come out strongest. The headline combination is WIDE — Window locks, Internal lights on timers, Double/dead door locks, External sensor lights — which is associated with homes being ~49x more protected than homes with no security at all.
And the alarm? The same body of work finds burglar alarms and dummy alarms alone confer less protection than no security — a null-to-negative association. A companion paper is bluntly titled "Do Burglar Alarms Increase Burglary Risk?" (Tilley et al., 2015): alarms went from protective in early-1990s data to risk-associated by 2008–12.
The honest caveats: these findings are associational, not causal. Alarms are bought disproportionately by higher-risk households, often after a burglary, and the underlying data is 2008–2012. Nobody serious claims an alarm makes you less safe. The defensible reading is narrower and still damning for the marketing: an alarm alone is the wrong first £300. Locks and lights first; alarm later, if at all.
What burglars themselves say
In 2017, Co-op Insurance convened a panel of 12 reformed burglars and asked what actually put them off. Top of the list: CCTV cameras, then loud dogs, strong doors, a TV left on, and locked UPVC windows. Burglar alarms ranked 13th. The panel's explanation is the detail worth remembering: everyone ignores a sounding alarm. Decades of false activations have trained neighbours — and, as we'll see, the police — to tune them out. What burglars consistently want is an empty-looking house, which is exactly what the WIDE combination attacks.
Will anyone actually come?
Two numbers to hold onto. One: only 5.0% of residential burglaries led to a charge or summons in the year ending March 2026, and 72.4% closed with no suspect identified — so prevention is nearly everything. Two: under the NPCC's security-systems policy, an audible-only alarm gets no police response at all. A ringing bell box is treated like any 999 call: attended only with independent evidence of a crime in progress.
Guaranteed response requires a police URN, which requires an NSI/SSAIB-certificated installer plus a confirmed-activation system and certified receiving centre. Of the big consumer names, only ADT clears that bar. Verisure's receiving centre is SSAIB-certificated but Verisure is not a certificated installer — no URN; its "police response" is a verified 999 call. SimpliSafe dispatches Securitas private guards, not police. And even with a URN, three false alarms in a rolling 12 months and response is withdrawn.
The catch: what monitoring really costs over 5 years
Teaser prices hide the real number, so we compute five-year totals (all checked Aug 2026): a eufy no-fee kit from £159; Ring Pack L with the Multi plan about £769; SimpliSafe with pro monitoring roughly £1,664–2,264; ADT about £2,319 (keyholder tier — real police response starts nearer £3,300); Verisure an estimated £2,849–4,349, quote-only and rising. Two escalators deserve naming. Ring's basic plan went £2.50 → £3.49 → £4.99/month between 2022 and March 2024 — about 100% in two years. Verisure's residential terms permit annual rises of RPI plus up to a further 5%, on leased hardware you hand back at contract end.
Don't expect insurance to rescue the maths: Which? found alarm discounts of 2–15% of contents premium — call it £10–25 a year against £360–840 of monitoring fees. Worse, some policies then require the alarm set whenever the house is empty, or a claim condition fails.
Who should — and shouldn't — buy an alarm
Skip the monitoring contract if you're a typical owner-occupier in a typical-risk area: the evidence-first move is the ~£40 tier — check your window locks, two plug-in timers, use the deadlock, add a sensor light, and a £15 dummy bell box as a visible cue (weak alone; it earns its place in the combination). That's not a cop-out — it's the ~49x tier. Buy a real self-monitored system (£150–500) if you want detection and app alerts; you're the responder either way. Monitoring genuinely earns its keep for high-risk or repeatedly targeted homes, properties left empty for long stretches, and high-value policies that mandate an NSI/SSAIB monitored system — that's the honest customer list, and it's short.
Factual summary, not insurance or security advice; prices checked August 2026 and they move often — verify on the maker's site. Most makers our tool links to pay us nothing (the Verisure link may be an affiliate link), and the best option always ranks first even when it pays us less, or nothing.