Best Carbon Monoxide Detectors

The Kidde Smart Smoke + Carbon Monoxide Alarm is our top pick for 2026, praised for its reliable fire and CO detection, easy installation, and ability to send instant smartphone alerts. Reviewers noted it effectively reduces false alarms that might lead to battery removal, and it can interconnect with older Kidde models. While it lacks some advanced features of the discontinued Nest Protect, it offers a cost-effective smart home safety solution. It's ideal for those seeking a balance of functionality and affordability, though users with existing Nest systems may find better integration elsewhere.

Siterwell's standalone smoke and CO detector offers reliable 10-year battery life and wireless interconnected functionality for up to 18 devices. The Do Not Disturb mode provides relief from nighttime false alarms, while its compact, portable design makes it suitable for various locations including Airbnbs and RVs. Consumer Reports noted its ease of installation and accurate electrochemical sensor, though the device is limited to plug-in power with backup battery only. This makes it ideal for renters or those seeking affordable interconnected protection without hardwiring.

The SITERWELL Hardwired Interconnected Smoke & CO Detector offers affordable, reliable protection with a 10-year built-in lithium battery and the ability to connect up to 18 units throughout a home. According to reviewers, it provides clear voice warnings in both English and French, and installation is straightforward with included hardware. The device features a Do Not Disturb mode to silence false alarms during cooking, and includes visual indicators for operational status and fault conditions. While it's designed for hardwired installation, it can also be used wirelessly. This makes it a solid choice for homeowners seeking interconnected protection without the complexity of full hardwired systems, though it may not suit those wanting smart home app integration.