By clicking a retailer link you consent to third-party cookies that track your onward journey. This enables W? to receive an affiliate commission if you make a purchase, which supports our mission to be the UK's consumer champion.
Best smoke alarms: Which? Best Buys and expert buying advice
In this article
- The best smoke alarms from our tests
- The smoke alarms we tested
- The best heat alarms from our tests
- The heat alarms we tested
- Which? Don’t Buy smoke alarms and heat alarms
- How we test smoke alarms and heat alarms
- Smoke alarms for people who are deaf or who have hearing loss
- What's the best type of smoke alarm for my home?
Only smoke alarms that detect smoke and raise the alarm promptly and loudly enough in all of our smoke detection tests can become Best Buys.
We test them with smoke from fires fuelled by cotton, plastics, solvents and wood. Each smoke alarm is tested twice and needs to sound in good time in all eight tests to pass. Heat alarms need to detect rising heat promptly and loudly sound the alert.
While we've found many alarms that will always detect smoke, our thorough lab testing has also revealed nine alarms that didn't sound. Some failed every smoke detection test.
And the most expensive smoke alarms aren't always the best – some more affordable alarms did a better job in our tests than others that cost twice as much.
How our tests find you the best
We've tested 13 smoke alarms
We assess smoke alarms and heat alarms from different brands and at various price points to ensure you find an alarm that is safe and will do the job it needs to.
Detecting smoke
House fires are fuelled by anything flammable. We test smoke alarms with cotton, wood, plastic and solvent fires to make sure they sound in time, every time.
Rising temperatures
Heat alarms sense rising temperatures where smoke alarms aren't suitable, such as in the kitchen. We see if each can detect a range of temperature rises from different starting temperatures.
We also test...
The volume of each alarm is measured, from when they first detect danger and again after sounding for a few minutes - they all need to hit 85dB. Plus we look at how well interlinked alarms work.
The best smoke alarms from our tests
The biggest brands and the 13 most popular smoke alarms are listed in alphabetical order below.
Only logged-in Which? members can view the smoke alarm test results.
Join Which? to get instant access to our test results and Best Buy recommendations.
| Smoke alarm | Price | Score | Type/Power source | Wood fire | Plastics | Sound |
|---|---|---|---|---|---|---|
Sign up to reveal Get instant access to this and all our scores and recommendations Unlock tableDigital first month £5, then £8.99 per month, cancel at any time. Already a member? | Interlinked/Mains | |||||
| Standalone/Disposable batteries | ||||||
| Interlinked/Mains | ||||||
| Interlinked/Mains | ||||||
| Interlinked/Sealed 10-year battery | ||||||
| Standalone/Disposable batteries | ||||||
| Interlinked/Sealed 10-year battery | ||||||
| Interlinked/Sealed 10-year battery | ||||||
| Interlinked/Sealed 10-year battery | ||||||
| Interlinked/Sealed 10-year battery | ||||||
| Interlinked/Sealed 10-year battery | ||||||
| Interlinked/Sealed 10-year battery | ||||||
| Interlinked/Sealed 10-year battery |
Sign up to reveal
Get instant access to this and all our scores and recommendations
Unlock tableDigital first month £5, then £8.99 per month, cancel at any time.
Already a member?
Log in
Date tested: February 2026, June 2024, June 2022 and June 2021. Page last checked: February 2026. We're not able to show every retailer and cheaper prices may be available.
The smoke alarms we tested
The smoke alarms we tested are listed in alphabetical order below.
Only logged-in Which? members can view the best smoke alarms from our tests.
Join Which? to get instant access to our test results and Best Buy recommendations.
Aico Ei146e Optical Smoke Alarm
Most recently tested February 2026
Standalone or interlinked Interlinked
Power source Mains with a back-up 9V battery included
Need to know Optical sensor, suitable for homes in Scotland, five-year warranty, can be linked with up to 12 other alarms, 10-year alarm life
Aico Ei3030 Multi-Sensor Fire and Carbon Monoxide Alarm
Available from Electricpoint (£66) and Screwfix (£94)
Most recently tested February 2026
Standalone or interlinked Interlinked
Power source Mains with a back-up 9V battery included
Need to know Multi-sensor, can detect smoke, heat and carbon monoxide (CO), suitable for homes in Scotland, 10-year warranty and alarm life, can be linked to other related Aico alarms including vibrating and strobing alarms
Aico Ei3016 Optical Smoke Alarm
Most recently tested June 2021
Standalone or interlinked Interlinked
Power source Sealed 10-year battery
Need to know 10-year battery, this alarm can be linked with other smoke and heat alarms, suitable for homes in Scotland
Aico Ei650RF RadioLINK+ Battery Optical Alarm
Most recently tested June 2022
Standalone or interlinked Interlinked
Power source Sealed 10-year battery
Need to know 10-year battery, this alarm can be linked with other smoke and heat alarms, suitable for homes in Scotland
Aico Ei3024 Multi-Sensor Fire Alarm (Smoke)
Most recently tested June 2022
Standalone or interlinked Interlinked
Power source Sealed 10-year battery
Need to know Can be interlinked through wireless or hardwiring, comes with optical smoke and heat detecting sensors, 10-year back-up sealed battery, suitable for homes in Scotland
Aico Ei660iRF RadioLINK+ Multi-Sensor Fire Alarm
Available from Acaselectrical.co.uk £58.49, Edwardes.co.uk £83.10, Masterlec.co.uk £58.49
Most recently tested June 2024
Standalone or interlinked Interlinked
Power source Sealed 10-year battery
Need to know 10-year battery, interlinked and can work in a circuit with other Aico smoke and heat alarms, suitable for homes in Scotland
Protect your home and loved ones. Discover our reviews of the best carbon monoxide (CO) alarms we've tested
FireAngel FA6611-R Smoke Alarm with Escape Light
Most recently tested February 2026
Standalone or interlinked Standalone
Power source Two disposable AA batteries
Need to know Optical sensor, five-year warranty, 10-year alarm life, standalone and not suitable for Scottish homes, includes two disposable AA batteries, comes with a bright escape light
FireAngel FP1640W2-R Pro Connected Smart Smoke Alarm
Most recently tested June 2021
Standalone or interlinked Interlinked
Power source Sealed 10-year battery
Need to know Can be linked with related FireAngel smoke and heat alarms, 10-year battery, suitable for homes in Scotland
Firehawk FHB10W Optical Wireless Smoke Alarm
Most recently tested June 2022
Standalone or interlinked Interlinked
Power source Sealed 10-year battery
Need to know 10-year battery, can be linked to other Firehawk smoke and heat alarms, suitable for homes in Scotland
Kidde 2030-DSR Optical Smoke Alarm
Most recently tested February 2026
Standalone or interlinked Standalone
Power source One disposable 9V battery (included)
Need to know Optical sensor, standalone and not suitable for Scottish homes, includes battery, three-year warranty, 10-year alarm life
Netatmo NSD01 Smart Smoke Alarm
Most recently tested June 2024
Interlinked or standalone Standalone
Power source Sealed 10-year battery
Need to know 10-year battery, smart (wi-fi connected), alerts will sound on your phone when the alarm sounds, can't be linked to other alarms and not suitable for homes in Scotland
The best heat alarms from our tests
The biggest brands and the most popular heat alarms are listed below.
Only logged-in Which? members can view the latest heat alarm test results.
Join Which? to get instant access to our test results and Best Buy recommendations.
| Heat alarm | Price | Recommendation | Type | Power source | Suitable for homes in Scotland |
|---|---|---|---|---|---|
Sign up to reveal Get instant access to this and all our scores and recommendations Unlock tableDigital first month £5, then £8.99 per month, cancel at any time. Already a member? | Interlinked | Mains | Yes | ||
| Interlinked | Mains | Yes | |||
| Interlinked | Sealed 10-year battery | Yes | |||
| Interlinked | Sealed 10-year battery | Yes | |||
| Interlinked | Mains | Yes | |||
| Interlinked | Mains | Yes |
Sign up to reveal
Get instant access to this and all our scores and recommendations
Unlock tableDigital first month £5, then £8.99 per month, cancel at any time.
Already a member?
Log in
Dates tested: June 2022 and June 2021. Page last checked: February 2026. We are not able to show every retailer and cheaper prices may be available.
The heat alarms we tested
The heat alarms we tested are listed in alphabetical order below.
Only logged-in Which? members can view the best heat alarms from our tests.
Join Which? to get instant access to our test results and Best Buy recommendations.
Aico Ei3014 Heat Alarm
Most recently tested June 2021
Standalone or interlinked Interlinked
Power source Mains powered
Need to know Interlinkable and suitable for homes in Scotland, mains powered with a sealed back-up battery, 10-year guarantee
Aico Ei3024 Multi-Sensor Fire Alarm (Heat)
Most recently tested June 2022
Standalone or interlinked Interlinked
Power source Mains powered
Need to know Comes with a 10-year back-up battery, links to other Aico alarms, 10-year guarantee, suitable for homes in Scotland
Firehawk FHH10W Wireless Heat Alarm
Most recently tested June 2022
Standalone or interlinked Interlinked
Power source Sealed battery
Need to know 10-year battery, seven-year alarm warranty, large test button, suitable for homes in Scotland
FireAngel FP1740W2-R Pro Connected Kitchen Heat Alarm
Most recently tested June 2021
Standalone or interlinked Interlinked
Power source Sealed battery
Need to know 10-year battery, seven-year warranty, interlinkable with up to 15 other alarms, suitable for homes in Scotland
Kidde Firex KF30 Interconnectable Heat Alarm
Most recently tested June 2021
Standalone or interlinked Interlinked
Power source Mains powered
Need to know Comes with a 9V back-up battery, can be connected to more than 20 Kidde alarms, suitable for homes in Scotland, six-year warranty
Hispec HSA/BH/RF10-PRO Heat Alarm
Most recently tested June 2022
Standalone or interlinked Interlinked
Power source Sealed battery
Need to know Can be connected to up to 20 other Hispec alarms, suitable for homes in Scotland, 10-year battery
Which? Don’t Buy smoke alarms and heat alarms
Buying the right smoke alarm could be one of your best decisions – it won't cost the earth to do this, but it could save your life. The Don't Buy alarms featured in the two photos here are to be avoided as none were able to detect smoke reliably in our tests, and in many cases they failed to sound in any of our eight smoke detection tests.
Eight of the nine Don't Buy smoke alarms were bought through online marketplaces and are unbranded, or came branded with the name of the online seller we bought them from. So if you have an alarm that looks like any of those featured, replace it with an alarm from a recognised brand available on the high street or through a well-known retailer's websites.
When buying smoke alarms, heat alarms and carbon monoxide alarms, our research shows that it's best to avoid cheap, unbranded products from online marketplaces, as all those we tested went on to fail some or all of our detection tests.
Find out more about how Which? is not influenced by product manufacturers or retailers and how your support helps us to stay editorially independent
How we test smoke alarms and heat alarms
We test smoke and heat alarms to British test standards in lab conditions to find the alarms that will sound every time you need them to.
Smoke alarm tests are carried out in accordance with the smoke alarm devices standard BS EN 14604. Heat alarm tests are carried out in accordance with the BS EN 5446-2:2003 standard, fire detection and fire alarm devices for dwellings.
Smoke alarm tests
- Smoke detection tests We test with four different test fires, fuelled by cotton, wood, solvents and plastics. We test every model of smoke alarm in each fire scenario twice.
- Detecting smoke every time Smoke alarms need to detect smoke and sound the alarm promptly before our test chamber becomes too smoky.
- Sound test We run a sound test to measure the noise emitted by the alarm when it sounds. All alarms need to hit 85 dB (A) or higher.
- Interlinking test We check that when the smoke alarm sounds the interlinked heat alarms will also sound. And we do the reverse in our heat alarm tests.
Heat alarm tests
- Slow temperature rise test We measure the responsiveness of each alarm to slow temperature rises. In our tests, we raise the temperature by 1°C per minute until the maximum temperature is reached.
- Typical temperature test We measure whether alarms operate and respond correctly over a range of temperature rises between 1°C and 30°C per minute.
- High temperature test We check whether the alarm is able to function correctly at high temperatures when the temperature begins to rise rapidly.
- Reproducibility test We repeat our tests to check whether the alarms continue to respond to rises in room temperature correctly every time.
- Sound test We measure how loud the alarms are initially when they sound and then again after they have been sounding for a few minutes. The target is 85 dB(A).
We regularly revisit the smoke alarms and heat alarms on sale to see if there are any more popular models that need testing – and when we find them, we do. We don't accept freebies from product manufacturers or retailers.
Smoke alarms for people who are deaf or who have hearing loss
If you are deaf or have hearing loss, you'll need an alarm that alerts you to the danger in ways other than sound. Attachments are available for smoke alarms that use vibrating pads and strobing lights to trigger when the alarm detects smoke.
To see how products like this work, we tested the Aico-Ei170RF Radio-Interlinked Strobe and Vibration Pad and connected it to the Aico Ei3030 Multi-Sensor Fire and Carbon Monoxide Alarm (£94) during our smoke detection tests. To link the two alarms together, you'll need to buy the Aico SmartLINK Module Ei3000MRF.
The purpose of the strobe light and vibration pad is to alert deaf people that there’s smoke in the air – the light strobes and the pad, which is intended to live under a pillow as you sleep, vibrates when the alarm is triggered.
In our tests, once we'd linked the three products together the smoke alarm detected the danger, sounded the alarm and the strobe and vibration pad sprung into action.
Find out more about how Which? is not influenced by product manufacturers or retailers and how your support helps us to stay editorially independent
What's the best type of smoke alarm for my home?
- Optical smoke alarms Optical (or photoelectric) alarms are light sensors containing an infrared LED, which pulses a beam of light into the sensor chamber every few seconds to check for smoke particles. As smoke enters, the light is scattered onto the photodiode light receptor, triggering an alarm. Historically, these were good at detecting the larger smoke particles from slower smouldering fires, but as technology has advanced, an optical alarm is now a good choice for most rooms in the home other than the kitchen, where you'll need a heat alarm.
- Ionisation smoke alarms This type of smoke alarm ionises the air between two electrodes, creating a small current inside the chamber. Smoke particles change the balance of the current; when this happens, a signal is sent and the alarm sounds. They were believed to be good for dusty areas like lofts, but they're now being phased out. So if you have an ionisation alarm, you should replace it with an optical alarm when it reaches the end of its life.
- Smart smoke and heat alarms Smart alarms send an alert via an app on your smartphone when danger is detected in your home. Smart alarms themselves don't need wi-fi signal to sound, so if the wi-fi is down, the alarm will still detect danger and sound. However, it does need to be connected to wi-fi in order to send an alert to your phone.
- Interlinked smoke and heat alarms Interlinked smoke alarms can be linked to other related smoke or heat alarms from the same manufacturer so that, when one senses danger, they all sound. In Scotland, since February 2022, interlinked smoke and heat alarms have needed to be fitted in all homes.
- Heat alarms Heat or thermal alarms detect hot air instead of smoke. The alarm is triggered when the temperature within the sensor chamber reaches over 58°C – generally when a fire is well established. You can put them in kitchens and garages because they’re not prone to false alarms from cooking or exhaust fumes.
Where should I place my smoke alarms?
To get the best response from your alarm, it should go in the centre of the ceiling, away from obstructions or dead spaces, such as where the walls and ceiling join. You should be able to hear it clearly across the whole space it's intended to cover, so bear this in mind as you look around your home and consider the risks.
If anyone in your family might struggle to hear it – if, say, they have a hearing impairment, or they're a particularly heavy sleeper – then you may want to set up your alarms to account for that.
How do I maintain a smoke alarm?
Smoke alarms need very little maintenance, but follow these simple steps to keep yours in good working order.
- Installation date and expected alarm lifetime Write on the smoke alarm itself the day it was installed, and the date that it should be replaced.
- Manufacturer instructions Follow the manufacturer's guidance on the installation, location and maintenance of the alarm.
- Regular testing Use the test button to test the smoke alarm weekly.
- Change the battery If your alarm comes with disposable batteries, change them each year.
- Clean your smoke alarm Gently vacuum inside the case (using the soft brush attachment) to remove dust from the smoke alarm sensors. If the case doesn't open, vacuum through the holes.
How to install a battery in a smoke alarm
This is an easy job. Alarms that use disposable batteries typically need a 9V battery or AA batteries.
It's a good idea to install batteries before attaching a new alarm to your ceiling. When you need to change them, the cover of the alarm will flip down to allow you to access the battery compartment.
Always test your smoke or heat alarm straight after replacing the batteries to make sure that it's still working.
How often should you change a smoke alarm battery?
This is likely to be an annual job if you have a smoke or heat alarm powered by disposable batteries, so make a point of doing this every year.
If a year hasn't passed and your alarm is chirping, this is another sign that the batteries need replacing, as measuring their lifespan is not an exact science.
Can you use rechargeable batteries in smoke alarms?
It's best to use disposable batteries in smoke and heat alarms. Rechargeable ones lose their charge more quickly, so they'll need to be replaced more frequently.
This can be inconvenient, while also posing a safety risk, if the alarm is without batteries while the rechargeable ones are being charged.
For a product this critical, and for the sake of safety and convenience, it's best to use a disposable battery that will last for a long time.
Why is my smoke alarm beeping?
If your smoke or heat alarm is chirping intermittently and uses replaceable batteries, this is a sign that the batteries need to be replaced.
When an alarm of any design – mains, sealed battery, replaceable battery – chirps, it can also mean it's at the end of its working life, which is usually 10 years. So if your alarm is chirping and is around 10 years old, it's time to get a new one.
A continuous sound coming from your smoke or heat alarm might indicate that it has become damaged or developed a fault. In any case, if an alarm emits a continuous sound that isn't the very loud alarm triggering, replace it as soon as you can.
What kind of smoke alarms and heat alarms are required in Scotland?
All homes in Scotland need to have interlinked smoke and heat alarms installed. Homes that have a fuel-burning appliance, such as a boiler, open fire or log burner, will also need to have a carbon monoxide (CO) alarm installed in the room the appliance is in, although the CO alarm doesn’t need to be interlinked.
A smoke alarm will need to be installed in the room you use most and you need to install an interlinked heat alarm in the kitchen. The new regulations also require interlinked smoke alarms to be fitted in all hallways and landings in homes in Scotland. These should be mains powered or come with a sealed battery rather than with replaceable batteries.