The best HomeKit smoke and CO detector for you will depend very much on your needs and where you live. The benefits of having any kind of smoke and CO detector in your house should be obvious, and sometimes not having one can even be against the law. A traditional smoke detector can detect smoke or head caused by fires (or potential fires), alerting you to danger before things get out of hand. Having a smoke detector can, at the very least, sometimes save you from burning dinner, other times, it could mean the difference between life and death.
Likewise, a CO alarm is vital in detecting deadly carbon monoxide gas in your home. This otherwise colorless, odorless liquid, can be emitted from appliances such as boilers and heaters, fireplaces, or even an idling car. So if a CO and smoke detector can keep you safe, what can a smart version bring to your home?
By and large smart smoke and CO detectors, especially ones that work with HomeKit, give you much more control over your alerts and the status of your detector, as well as interoperability with your smartphone and other devices. For example, our favorite pick, the First Alert OneLink Safe & Sound, can give you remote notifications directly to your phone 24/7. This means you'll be alerted to potential fires or CO detection in your home if you're out shopping, at work, or even abroad. You can also track the battery life of all your detectors without that annoying beeping warning, and you can easily silence alerts or false alarms without climbing a ladder or jumping on a chair to prod it. Our top pick even has a built-in AirPlay 2 speaker, doubling as a recessed smart speaker for your ceiling.
As you can see, going smart is an easy way to elevate your smoke and CO detectors in your home. The market is quite limited and there aren't too many to choose from (especially between Europe and the U.S.), but the ones we have found are all excellent in their own way.
Quick List
Best for connectivity
Battery operated: Yes
Sensor type: Electrochemical, Photoelectric
Dimensions: 7 x 7 x 2 inches
+ All-in-one device
+ Both smoke and carbon monoxide sensor
- Expensive
- Some users experience wireless issues
The OneLink Safe and Sound combines a smoke and carbon monoxide detector, AirPlay 2 speaker, customizable nightlight, and voice assistant with Alexa, all into one incredibly smart package. This hybrid HomeKit accessory connects to your existing wiring along your home's Wi-Fi, and its interconnect feature extends smart notification coverage to your smoke detectors.
Best for wireless systems
Battery operated: Yes
Sensor type: Electrochemical, Photoelectric
Dimensions: 5.88 x 5.88 x 1.57 inches
+ Battery operated
+ Simple connection
- Occasional false alarms
- Non-replaceable rechargeable batteries
This HomeKit-enabled smart detector from First Alert brings portability to the traditional safety monitoring form factor. First Alert's monitor runs solely on replaceable batteries for up to five years, allowing placement anywhere in your home without worrying about having existing wiring.
Best on a budget
Battery operated: Yes
Sensor Type: Smoke detector
Dimensions: 2 x 4.68 x 4.68 inches
+ Simple to use
+ Easy to mount
- Requires a hub
- Only available in Europe
This smart solution from Bosch offers affordable smoke detection that installs in seconds thanks to a peel-and-stick design. There are a few downsides, though, as it is only available in Europe and requires a Bosch Smart Home Controller for HomeKit and Home app integration.
Best for hardwiring
Battery operated: Yes, battery backup
Sensor Type: Electrochemical, Photoelectric
Dimensions: 5.88 x 5.88 x 1.57 inches
+ Wired connection
+ Works with other systems
- Harder to fit
- Not much less than the wireless version
Like its battery-powered counterpart, the OneLink Hardwired Smoke and Carbon Monoxide Detector brings smarts with a classic design. In case of emergency, this OneLink detector can send notifications directly through the Home app, and a built-in 10-year backup battery provides peace of mind even when the power goes out.
Best design
Battery operated: Yes
Sensor Type: Non-Dispersive Infrared
Dimensions: 4.5 x 4.5 x 1.7 inches
+ 10 year battery life
+ Simple to fit
- Expensive
- Not suitable for garages
Another European-only option is the Netatmo Smart Smoke Alarm which works right out of the box with HomeKit. In addition to Bluetooth Low Energy, Netatmo's detector supports Wi-Fi enabling timely notifications, and an 85-decibel siren ensures that everyone in the home is aware of all of the action.
Best for European residents
Battery operated: Yes
Sensor Type: Smoke detector
Dimensions: 7.1 x 7.1 x 4 inches
+ Replaceable batteries
+ Air quality monitoring
- Expensive
- Needs hub
Bosch's other European-only HomeKit smoke detector takes things up a notch by mixing in additional sensors for air quality, temperature, and humidity. With the Bosch app, you can view air quality trends and more, and of course, with HomeKit, you can create automation with other smart home accessories.
Why OneLink's Safe and Sound is our pick for best HomeKit smoke detector
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Are you looking for the absolute best HomeKit smoke detector for the Home app? Then look no further than the OneLink Safe and Sound. This feature-rich accessory includes an AirPlay 2 speaker, Amazon's Alexa, a customizable LED nightlight, and an interconnectivity function that extends its smart capabilities to all of your existing smoke and CO detectors.
Do you need to add a smoke and CO detector to a room without existing wiring? Then the OneLink Battery-Powered Smoke and CO Detector is your best bet. This unit looks like a typical smoke detector, but it comes with replaceable batteries that last up to five years and can be mounted just about anywhere. If you don't mind doing some hardwiring yourself, then the Hardwire version is also a great option.
Choosing the best smart smoke and CO detector for HomeKit
There are a couple of major considerations you should make when choosing a smart smoke and CO detector. As the NFPA notes, the biggest is probably the choice between ionization (electrochemical) and photoelectric sensors. The former is better for fast-burning, flaming fires, while the latter is more appropriate for smoke and smoldering fires (an unattended cigarette, for example). Generally, the NFPA recommends a detector that can do both, which again brings us back to our top pick, the OneLink Safe and Sound.
The other main consideration is battery versus mains power. A hardwired detector that runs off your home's electricity will offer you peace of mind knowing you'll never run out of battery power. However, it will be more difficult to install and could be vulnerable to failure in the event of a power cut or outage. Conversely, a battery-powered detector will require less electric wizardry, but you'll need to keep on top of the battery to make sure it's always operational. Thankfully, the "smart" nature of it will make keeping track of battery levels easier.
