Best carbon monoxide alarms for UK homes (2026)
Our pick for most homes is the FireAngel FA3322, a clear digital 10-year alarm with no battery changes; the Aico Ei208 is the fit-and-forget choice beside a gas boiler, hob or wood burner. A carbon monoxide alarm is one of the few bits of safety kit that genuinely saves lives — CO is invisible, odourless, and produced by any fuel-burning appliance from a boiler to a camping stove used indoors. If your home has gas, oil, solid fuel or an open flame anywhere, you need one. Here's how to pick a good one and where to put it.
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By Tom Calder · Updated 5 November 2026 · 9 products, all price-tracked
Our picks
Photo: AmazonFireAngel FA3322 10-Year Digital Carbon Monoxide Alarm
Bedrooms and living rooms wanting a clear, readable CO alarm with no battery faff
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.
Photo: AmazonAico Ei208 Carbon Monoxide Alarm
Households with a gas boiler, hob, open fire or wood burner who want fit-and-forget protection.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.
Photo: AmazonAico Ei3018
A home rewiring or new build where CO alarms are fitted on the mains circuit.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.All 9 compared
Photo: AmazonOur top pickBedrooms and living rooms wanting a clear, readable CO alarm with no battery faff
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Our verdict
The FA3322 is an independently well-rated CO alarm with a sealed 10-year battery, so it's fit and forget. It's a sound, low-maintenance choice for most UK homes.
Worth knowing: Costs more than a basic non-digital CO alarm
Who shouldn't buy it: Skip it if you just want the cheapest compliant alarm — a basic FireAngel model without the digital display meets the same BS EN 50291 standard for less.
Read the full review →Photo: AmazonRunner-upHouseholds with a gas boiler, hob, open fire or wood burner who want fit-and-forget protection.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Our verdict
A professional-grade CO alarm from a trusted UK manufacturer, with a sealed 10-year lithium battery so there are no cells to change and nothing to forget. It costs more than a supermarket alarm, but the electrochemical sensor and BS EN 50291 Kitemark make it a sensible long-term buy for any home that burns fuel.
Worth knowing: No digital display, so you cannot see a live CO ppm reading at a glance
Who shouldn't buy it: You want a live digital ppm readout, or you need alarms that interlink across the house so one sounding triggers the rest, in which case choose a display model or the RadioLINK Ei208WRF instead.
Photo: AmazonAlso goodA home rewiring or new build where CO alarms are fitted on the mains circuit.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Our verdict
A hard-wired CO alarm from Aico's 3000 series with a rechargeable lithium back-up, a 10-year operational life and a 10-year guarantee. Up to 12 alarms can interconnect by wire, or wirelessly with the optional Ei3000MRF module. It is the choice for a fixed, permanent installation, not for a quick plug-and-place fix.
Worth knowing: Aico's manual says mains alarms must be installed by a qualified electrician
Who shouldn't buy it: You rent, or want something you can fit yourself in minutes, in which case a battery alarm such as the Aico Ei208 or FireAngel FA3322 fits better.
A battery CO alarm with a live ppm readout, for a bedroom or a caravan.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Our verdict
The digital sibling of the FA6813: the same 10-year electrochemical sensor, but with an LCD that shows the current CO level in parts per million and a memory of past alarms. The AA cells are replaceable, which keeps running costs low but means a periodic check. A sensible step up from an LED-only alarm.
Worth knowing: Replaceable AA cells rather than a sealed battery
Who shouldn't buy it: You want alarms that link together across the house, or a sealed battery you never touch, in which case the Aico Ei208WRF fits better. Householders in Scotland should check current Scottish alarm rules first.
An affordable, standards-approved CO alarm for a room with a gas boiler, fire or stove.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Our verdict
A dependable, no-frills carbon monoxide alarm from a well-known brand, Kitemarked to BS EN 50291 with a 10-year sensor. It does the essential job well, though there is no digital readout and you will need to keep the AA batteries fresh.
Worth knowing: LED indicators only, so you cannot read the actual CO ppm level
Who shouldn't buy it: You want a digital display showing live CO levels or a fully sealed battery you never have to touch, in which case the digital 5DCO or a sealed-battery model suits better.
Read the full review →
Households who want a clear digital CO readout without paying premium-brand money.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Our verdict
A dependable, EN 50291-compliant CO alarm that shows the actual CO level on its screen rather than just sounding off, at a genuinely low price. The 10-year sensor life and replaceable AA batteries make it easy to live with, though it works alone rather than linking to other alarms.
Worth knowing: Standalone only, it won't interconnect with alarms elsewhere in the house (the separate CO03D-W does)
Who shouldn't buy it: You want a fully sealed, fit-and-forget 10-year unit with no battery changes, or a whole-home system where every alarm sounds together, in which case choose a sealed-battery or interconnected model instead.
A low-cost, portable CO alarm for a bedroom, caravan or holiday let.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Our verdict
A plain battery-powered alarm from a specialist UK brand, with a 10-year electrochemical sensor and AA cells you replace yourself. It also carries the caravan and boat standard, so it travels well. It has no digital readout, so it sits beside FireAngel's FA6812 on this page as the cheaper, simpler choice.
Worth knowing: LED indicators only, so no live ppm reading
Who shouldn't buy it: You want a live ppm display (the FA6812 or X-Sense CO03D fit better) or a sealed battery you never touch (the FA3322 or Aico Ei208). Householders in Scotland should check current Scottish alarm rules first.
A small, budget-friendly CO alarm from a well-known brand for a room with a boiler or fire.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Our verdict
A compact, light alarm from Kidde with a 10-year electrochemical sensor and an end-of-life warning. Kidde's own datasheet lists EN 50291-1:2018 with the certificate still pending, so unlike the Kidde 5CO on this page it is not shown as Kitemarked. It suits a straightforward, low-cost replacement where a Kitemark is not a priority.
Worth knowing: Kidde's datasheet shows the EN 50291-1 certificate as pending
Who shouldn't buy it: You want a Kitemarked alarm (choose the Kidde 5CO or an Aico), a live ppm display, or an alarm for a caravan, motorhome or boat, which Kidde says this model is not designed for. Householders in Scotland should check current Scottish alarm rules first.
Sold out right now (1)
The shop says these are sold out today. We check stock every hour, and each one moves back up the list when it returns.
A multi-room home that wants wireless interlinked, fit-and-forget CO alarms.
Our verdict
The wireless version of the Aico Ei208 already on this page: the same sealed lithium battery and 10-year electrochemical sensor, plus a RadioLINK+ module so alarms signal each other without wiring. It costs more than the standalone Ei208, but it is the easiest way to get interlinked CO alarms on this page.
Worth knowing: Dearer than a standalone alarm
Who shouldn't buy it: You only need one standalone alarm, in which case the Aico Ei208 costs less; or you want a live ppm readout.
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Before you buy
The one spec that matters is the standard
A CO alarm must be marked EN 50291 (the British/European standard) and ideally carry a Kitemark or equivalent. That's what tells you it's been independently tested to detect CO at the right levels and sound in time. A cheap unbadged detector is worse than useless because it breeds false confidence. Note that Kidde lists the 2030-DCR's EN 50291-1 certificate as pending, so it is not shown as Kitemarked.
After that, it's about sensor life and power.
CO sensors don't last forever — most alarms have a sealed 7-year or 10-year life and then must be replaced (the alarm bleeps at end of life). Sealed-battery models (such as the FireAngel FA3322 and Aico Ei208) need no battery changes for their whole life; replaceable-battery models are cheaper upfront. Mains models such as the Aico Ei3018 must be installed by a qualified electrician, and interlinked alarms (the Ei208WRF and Ei3018) let one alarm set off the others. A digital display is a nice-to-have that shows CO levels and helps you spot a low-level chronic leak, not just an emergency.
Placement is part of buying
Fit an alarm in every room with a fuel-burning appliance, roughly at head height and about 1–3 metres horizontally from the appliance — not right next to it, and not in a sealed cupboard. Test it monthly and note the replacement date. If it ever sounds, get everyone out into fresh air and call the gas emergency line (0800 111 999; 0800 002 001 in Northern Ireland) or 999.
We verify every product's specifications against at least two independent sources, re-check its UK price and stock on a schedule where we can track it automatically, and cross-check safety-relevant claims against official guidance. Every review is labelled Researched or Used and reviewed by us: where we've bought a product, or been sent it free, and used it ourselves, its review says which; where we haven't, our verdict is a considered spec-and-evidence comparison, not a hands-on test. When two products are close, commission can decide which one we pick. A clearly better product always wins. Read our full methodology →
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Common questions
What's the best carbon monoxide alarm in the UK?
For bedrooms and living rooms, the FireAngel FA3322, a 10-year digital alarm that is easy to read and needs no battery changes. Beside a gas boiler, hob, open fire or wood burner, the Aico Ei208 is the fit-and-forget choice. On a budget, the Kidde 5CO is an affordable, standards-approved alarm. Whichever you choose, check it meets the British/European standard for CO alarms (see below).
Do I really need a carbon monoxide alarm?
Yes, if your home has any fuel-burning appliance — a gas or oil boiler, gas hob, open fire, wood burner or similar. CO is invisible and odourless, and an alarm is the only way to detect it. It's cheap, life-saving and, in many rented homes, a legal requirement.
What standard should a CO alarm meet?
Look for EN 50291 marked on the alarm, ideally with a Kitemark or equivalent third-party certification. That confirms it's been independently tested to detect carbon monoxide at the correct levels. Avoid any detector that doesn't clearly state the standard.
Is a carbon monoxide alarm the same as a smoke alarm?
No — they detect different things and you need both. A smoke alarm detects fire; a CO alarm detects carbon monoxide gas. Some combined smoke-and-CO units do both, but a standard smoke alarm will not warn you about CO.
How long do CO alarms last?
The sensor has a limited life — typically a sealed 7 or 10 years — after which the alarm signals end of life and must be replaced. Sealed-battery models last their whole life with no battery changes; replaceable-battery ones are cheaper but need new batteries.
Where should I put a carbon monoxide alarm?
In each room with a fuel-burning appliance, at about head height and roughly 1–3 metres horizontally from the appliance — not directly above or beside it, and not shut in a cupboard. Test it monthly.
What do I do if my CO alarm goes off?
Get everyone out into fresh air immediately, don't stay to investigate, and call the free national gas emergency line on 0800 111 999, or 0800 002 001 in Northern Ireland (or 999 if anyone is unwell). Only return when you're told it's safe.
