The best carbon monoxide detectors

Keep you and your family safe with one of the best carbon monoxide detectors.

Best carbon monoxide detector

by Eleanor Weaver |
Updated on

We've all heard the annoying sound of a smoke alarm when a Sunday fry-up doesn't go to plan, frantically opening windows to make the beeping go away. Much like a smoke alarm, a carbon monoxide detector operates by alerting us of the presence of lethal gas, which is crucial to ensure the safety of any household.

When it comes to choosing the right detector, there's no room for error. For that reason, we've rounded up the best carbon monoxide detectors in terms of quality, longevity, and price.

Best carbon monoxide detector at a glance:

Top pick: Google Nest Protect - view on Amazon UK
Best for volume: Honeywell XC70 Carbon Monoxide Detector Alarm - view on Amazon UK
Best for energy-saving: X-Sense Carbon Monoxide Alarm - view on Amazon UK

But what causes carbon monoxide in the home? Appliances such as boilers, gas fires, central heating systems, and open fires can all lead to carbon monoxide exposure, where gas does not burn fully. If a household appliance, like a cooker or boiler, has not been installed or maintained adequately, this could lead to the presence of carbon monoxide. Camp stoves, charcoal grills, and burning fuels in an enclosed space can also lead to the build-up of carbon monoxide in your home.

Luckily, there are plenty of things you can do to prevent the release of carbon monoxide (CO), the main one being installing a carbon monoxide detector.

Remember, if your CO detector ever sounds, leave your house immediately and call 999.

The best carbon monoxide detectors

Top pick

Google Nest Protect 2nd Generation Smoke + Carbon Monoxide Alarm
Price: £94.35 (was £150)

A truly 'smart detector', this device uses a friendly human voice to give you an early warning of danger and tells you exactly where the danger is. It can connect to your phone, alerting you of a problem even when you're not home, and if carbon monoxide reaches dangerous levels, the alarm is sounded, along with pulsing red lights.

The Nest Protect performs tests on itself over 400 times a day so you don't have to, and even lights up every time you walk beneath it for some assistance en route to your midnight snack.

Customer review: "Wow, I have to say I am very impressed! Works like magic, very modern design and will glow when it's dark and passing by it. I am very happy with the purchase. You can control it from your mobile, it will show you a timeline of all the events, just fantastic. Hope it will work like that all the time. A little bit expensive but I still think it's worth the price. All-round brilliant and delivered very speedily!"


  • Tells you what's wrong and where the problem is
  • Phone alerts include for low-battery, smoke, carbon monoxide, sensor failure
  • Detects smoke and carbon monoxide


  • Requires wired installation


Fireangel's multi-function carbon monoxide detector will provide audible and visual warnings of the early presence of CO in your home. The LCD display continuously measures levels of carbon monoxide, alongside humidity and temperature. The 10-year lifespan means you don't need to worry about changing it every so often, and the quiet self-test will give you peace of mind about the effectiveness of the product. It's also portable, meaning you can take it with you to your holiday home.

Customer review: "Does its job & sounds the alarm - went off at 2 am one morning during July 17 in the kitchen where we subsequently found someone (me) hadn't turned off one of the gas rings completely - called out S&SE Networks & they sent out an on-call engineer who noted that there's no immediate danger from leaving one ring on & only a light reading of carbon monoxide, not deadly. The product works, the alarm is loud. Recommended."


  • Automatic self-diagnostic check
  • Multi-function digital screen and room thermometer
  • Large test and silence button


  • Doesn't display all the functions at once - need to cycle through with the button

Best for portability

With a seven-year lifespan, the Mercury alarm is a fantastic and reliable carbon monoxide detector. It's battery-operated, meaning it will still work during power cuts and provides clear, confident CO readings on the LCD display. The LED lights will beam green for power, amber for fault, and red for alarm, keeping you alert and informed at all times.

Customer review: "Very easy to install, can be free-standing or wall-mounted, comes with x2 AA batteries plugs and screws. Audible alarm is loud and would not be missed, we have ours in the loft of our bungalow as the boiler is up there and is easily heard when testing. The unit is very robust and well made and also looks good. Good clear indicators and the LCD displays are on at all times and are easy to read."


  • LCD display with continual readout
  • Tested in an approved lab
  • Easy to set up


  • Not the easiest to read

Best for energy-saving

Not only is this device modern-looking and sleek, but it's also highly accurate and efficient. Designed in a way to give you the earliest possible warning of carbon monoxide presence, the X-Sense alarm will put your mind at rest. The unit is battery-operated, so there's no need to worry about playing around with wires or access to wall outlets, and measurements are taken every 10 seconds, clearly displayed on the large LCD display.

Customer review: "I have fitted this alarm in my living room and it was so easy to install, it's very smart and appears to be doing a great job. I am very happy with this product and would recommend it."


  • Low energy consumption
  • Large LCD display
  • Easy to set up


  • Not made to be freestanding

Best for versatile positioning

We love that this energy-saving carbon monoxide detector is battery-powered and provides a precise and stable reading via an electrochemical CO sensor. The large digital LCD display will let you know the exact readings, and an alert will be sent as soon as the battery needs changing. It's not quite as loud as the Honeywell alarm, but the alarm quickly sounds 85dB and flashes a red LED when a dangerous level of CO is detected.

Customer review: "This replaced an old unit which had time-expired. Straightforward to fit, tho I had to drill a new mounting hole as this base was a different size to the old unit. Now installed & seems to work fine. I like that it also displays the room temperature - not particularly useful, but helps give confidence that it’s working properly!"


  • Compact size
  • Option to be wall-mounted, ceiling-mounted or freestanding
  • Large LCD display


  • Instructions aren't the best

Best twin pack

Lifesaver Carbon Monoxide Alarm Twin PackCredit: Argos

Ensure the safety of your home by equipping it with a crucial defence against the 'silent killer,' carbon monoxide, with our reliable CO alarm. This twin pack is small and easy to use. It can be installed on a wall or ceiling for convenience.

Customer review: "I brought this as a replacement for my last Carbon monoxide alarm of the same model. The alarm I am replacing lasted seven years, so I am hopeful this will last as long."

Best easy to use carbon monoxide alarm

EITO - Carbon Monoxide DetectorCredit: Amazon

When the concentration of carbon monoxide reaches the alarm value, the red LED flashes and triggers a buzzer alarm.

Customer review: "Easy instructions to set up. Seems good quality. A compact unit, giving a digital indication of any CO present at a great price."

Best carbon monoxide detector FAQs

Where should I install my CO detector?

Place your carbon monoxide detector high on the wall in any room that contains a fuel-burning appliance. You should also place a detector on every floor of your house in the hallways, close enough to bedrooms so that you can be alerted should the detector sound in the middle of the night.

How to prevent carbon monoxide poisoning

Prevention is key when it comes to carbon monoxide, and these are a few things that will help hinder the chance of exposure.

• Install battery-powered carbon monoxide detectors and place them in hallways close to bedrooms or spaces where people sleep. Make sure to change the batteries once or twice a year, and replace your CO detector every five years.

• Have appliances regularly serviced by qualified professionals.

• Make sure your chimney is swept thoroughly once a year.

• You should never burn charcoal inside your home.

• Never use a gas appliance that isn't properly vented.

• You should never use a generator in your home or within six metres of a window or vent.

What causes carbon monoxide in the home?

Carbon monoxide can result from fuel-burning appliances such as boilers, gas fires, heating systems, cookers, open fires, and water heaters.

©Getty Images

How can you tell if there is carbon monoxide in your house?

Carbon monoxide is both odourless and colourless, meaning you can't see or smell it. This is part of what makes CO so dangerous and hard to detect.

The best, most effective way to tell if there is carbon monoxide in your home is by installing a CO detector. Having said that, there are some tell-tale signs which might let you know that something is wrong.

Things like heavy condensation in a room where there's an appliance or brown-yellow stains or soot around a fuel appliance are both signs of dangerous carbon monoxide levels.

If you have any concerns about CO exposure, leave your home and call the emergency gas number at 0800 111 999.

How does carbon monoxide affect the body?

According to the NHS, symptoms of mild carbon monoxide poisoning are as follows:

• Tension-type headache
• Dizziness
• Feeling and being sick
• Tiredness and confusion
• Flu-like symptoms
• Shortness of breath
• Stomach pain

Eleanor Weaver is the Deputy Homes & Garden Product Editor for Yours, specialising in home décor, furnishings and appliances. Having worked commercially on Yours magazine and for the past six years, she's previously hosted Yours Live events and loves looking for home inspiration online.


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