Best Smoke & Carbon Monoxide Alarms of 2026

"I’ve used this Kidde CO detector for 10 years and just replaced my original with the same model. It plugged straight into the outlet, has a backup battery, and the digital readout is clear and easy to understand. When my old gas boiler started leaking CO, this detector alerted me right away and probably kept my family safe. It’s not the cheapest, but the value and peace of mind are worth it. I even like that it can be wall-mounted and comes with the necessary hardware."

"I bought this because I live alone and wanted something simple to install and dependable for my safety. I followed the directions, tested it, and it met all my expectations. I would definitely recommend this to anyone who needs reliable protection in their home."

"The plug-in design with battery backup makes it so convenient, especially if the power goes out. The digital display shows CO levels clearly, and the alarm is very loud and responsive. Setup was a breeze, and the compact design means it doesn’t get in the way. I feel confident my family is protected with this detector."

"I've purchased this product twice, and I'm really happy with it. The installation is super simple, and I don't have to worry about batteries for ten years."

"I've relied on this brand for years because it's easy to install and always works as expected. Setup couldn't be simpler, and I have peace of mind."

"Unfortunately, I had a bad experience with two units. After only a few months, both started to go off randomly, even when nothing was wrong. Despite following all instructions, I had to dispose of them when they wouldn't stop alarming. This was really disappointing and stressful, especially for my pets."

"Replacing my old Kidde detector was simple—it snapped right in, and I didn't need to deal with hardwiring. The nonstop beeping from my expired alarms finally stopped. No complaints at all."

"Installation was a breeze, and I love that the battery is sealed and should last for ten years. The price was much better than in-store, and I appreciate not having to replace batteries all the time."

"I was disappointed because, despite high recommendations, these alarms started having false chirps within a year. I tried everything—cleaning, resetting, but nothing helped. Customer service is sending a replacement, so I hope my experience improves, but right now, I'm not planning to buy this brand again."

"I found it super easy to install and it works perfectly! I bought it to replace an old detector and really trust this reliable brand."

"The three pack was exactly what I needed. I could use the same mounting holes as my old detectors, and it's much better now that the batteries are replaceable and there's fault detection built in."

"I was happy with my purchase, even though I chose the used option to save money. It arrived in great condition, with all instructions and battery included, and fit just fine in my RV."

"After more than three decades as a master electrician, I can say these detectors are simple to rewire and install, even with the updated connectors. The loud alarm and reliable interconnect feature give me peace of mind knowing my family is protected. I always check with my own tools, and these units passed both smoke and CO tests. The inclusion of a Duracell battery and dust cover is a thoughtful touch. For the price, I'm extremely satisfied and feel secure."

"I'm very satisfied with the First Alert Combination Smoke & Carbon Monoxide Alarm. The installation was straightforward and the hardwired setup with battery backup reassures me that it works during outages. I appreciate the dual detection for smoke and CO—it’s a smart investment for home safety. The interconnectivity is a real advantage for larger homes. I highly recommend this dependable, easy-to-install product."

"We recently upgraded to this First Alert combination alarm and are extremely happy with its performance. The biggest benefit is the dual protection in a single device, which makes maintenance easier and keeps our home safer. It integrated seamlessly with our existing hardwired system, and we found installation to be quick and hassle-free. The brand reputation and quality construction make this a worthwhile choice for anyone looking to improve their home safety."

"I found these smoke detectors extremely easy to install—they fit my existing mounting rings and with the optional adaptors, I had them up and running in no time. Each unit passed all tests, has the built-in 10-year battery for peace of mind, and so far, they've been quiet and dependable with no false alerts. I appreciate not having to worry about battery changes for a decade!"

"After replacing my old wired detector with this Kidde model, I was relieved it matched my previous bracket, making installation quick and hassle-free. The 10-year battery is a huge plus—no more annual battery swaps. I’d recommend this for its reliable operation and straightforward setup."

"Unfortunately, I've had issues with false alarms and error messages after only a few months of use. The detector would beep and announce errors, sometimes going off daily. While Kidde's support was responsive and offered a replacement, I'm disappointed given my prior positive experience with this brand. I hope the replacement resolves the issue."

"I appreciated the straightforward installation, and the fact that the mounting plate fit perfectly for a clean look. It was easy to connect to my smart home system, and I like that I’m not stuck with a proprietary cloud service. Testing was simple and gave me confidence in its reliability."

"I had worried the new Kiddie detectors wouldn’t fit the old base plates, but they did—swapping out both took just 10 minutes. The only extra work was changing the plug, which was simple if you know basic DIY. AA batteries are a plus over pricier 9-volts. My only gripe is with Amazon’s flimsy packaging—these should be boxed, not bagged."

"Needed replacements quickly after false alarms late at night. Ordered these and they arrived next morning and installed with ease. Now all my alarms are the same model, and I didn’t need any extra tools or wiring. No more nuisance chirping or confusion."

"Installing these alarms was quick and straightforward—I swapped out my old detector in less than 15 minutes. The 10-year internal battery is a huge plus, and the peace of mind is totally worth the slightly higher price. I definitely recommend this product to others."

"I picked up several of these Kidde smoke and CO detectors for my home, and having all alarms interconnect really adds a new level of security. The LED indicator makes it easy to distinguish between smoke and carbon monoxide alerts. Setup was fast, just a simple wiring harness swap and mounting. Even though they're a bit bulkier than my old ones, the reliability and 10-year backup battery make them a great value."

"I was excited to upgrade to these Kidde hardwired detectors with a sealed battery backup that lasts a decade—no more annoying low-battery chirps at night! The only hiccup was the new connector design, which meant I had to change out the wiring instead of just using the old plug. Despite that, the build quality is excellent and the peace of mind is unbeatable. I'll keep upgrading the rest of my home with these."

"After updating my old detectors, I found installation to be straightforward and the units have been quiet, dependable, and well-built. The smart alert feature is reassuring, especially when I'm away. No false alarms or connectivity problems so far—these detectors are a solid, trustworthy choice for those looking to modernize without unnecessary complexity."

"I replaced my expiring NEST detector with this model and was pleased with the simple installation and integration with the Ring app. My main issue is that it beeps during firmware updates, which I don't find necessary. However, after the initial setup, it has remained silent and reliable, so I decided to replace all my NESTs with these. I would like the app to display the detector's expiration date in the future."

"As someone who relies on Ring, I appreciate that this is the first smoke/CO detector directly integrated with the Ring ecosystem. Although I wish there was a cordless option, wiring into my existing system was easy and the detector connected to Ring without hassle. It's reassuring to use a well-regarded, established brand for such an important device."

"I really appreciate how simple it was to set up this compact 2-in-1 smoke and carbon monoxide detector. The installation took just a few minutes, and the LCD screen is straightforward to read, letting me check the status instantly. Since it’s battery-powered and lightweight, I can use it both at home and while traveling without any hassle. The sound is loud enough to catch my attention, and the 10-year sensor lifespan gives me long-term peace of mind. It’s a solid and trustworthy device that blends into my space without being obtrusive."

"For my guest room, I needed something reliable yet uncomplicated, and this detector fits perfectly. Mounting it was straightforward once I added AA batteries, and the unit feels secure on the ceiling. What I value most is how it remains silent and calm during normal use—no unnecessary beeps or lights. The display only activates for important alerts, and I can easily distinguish between smoke and carbon monoxide warnings. The alarm is plenty loud for emergencies, yet it doesn’t overreact to everyday activities. It’s a dependable safety upgrade that’s simple to use."

"I chose this detector because of its modern design and ability to combine smoke and CO detection in one device. It was quick to install and, unlike older alarms, it doesn’t get triggered by steam from showers. The alarm is very loud and covers the whole house. I also like that the batteries are replaceable, so I don’t need to throw out the unit when they run out. It’s affordably priced and feels secure, giving me confidence that my home is well protected."