10 Best Smoke Detector Carbon Monoxide Detectors Combo 2025 in the United States

The Kidde Smoke & Carbon Monoxide Detector 2-pack is a practical choice if you're looking for an easy-to-use device that covers both smoke and carbon monoxide detection. It combines photoelectric and electrochemical sensors, which helps it detect smoke from fires and dangerous carbon monoxide gas effectively. One big plus is its 10-year battery life — you won't need to worry about changing batteries or annoying low-battery chirps for a decade, which also saves money over time. Installation is simple since it’s battery powered and wireless; just mount it on the ceiling and click it into place. It has clear LED lights to show its status, so you can easily see if everything's normal, if there's a problem, or if an alarm is sounding.

The 85-decibel alarm is loud enough to alert you even if you’re in another room. It also features a test and hush button, handy for checking the alarm works or silencing false alarms, which are less common thanks to its improved sensing technology that reduces alerts from normal cooking smoke. However, it doesn't support interconnectivity, so multiple alarms won't communicate with each other, which might be a drawback if you want whole-home coverage with linked alerts. Its operating conditions are quite standard, suitable for typical home environments.

This detector is ideal for homeowners who want a reliable, low-maintenance, combo smoke and CO alarm without complicated wiring or smart home features. It has a solid warranty and customer feedback supports its dependable performance, though after 10 years, the entire unit needs replacing, not just the battery.

The First Alert SMCO100 is a battery-operated combo alarm that protects against both smoke and carbon monoxide, making it a practical choice for home safety. It uses photoelectric sensors, which are especially good at detecting smoldering fires and reducing false alarms from cooking. This means fewer annoying nuisance alarms compared to traditional models.

Since it runs on 2 included AA batteries, installation is simple and you don’t have to worry about wiring, though you will need to replace batteries periodically. The alarm includes a test/silence button for easy checks and temporarily silencing false alerts. It also has an end-of-life warning that notifies you when it’s time to replace the unit, helping to ensure ongoing protection. The 3-pack offers good value for covering multiple rooms or floors. However, since these smoke/CO detectors are not interconnected, alarms won’t sound simultaneously throughout the house if one detects danger, which could be a drawback for larger homes.

This First Alert model provides a reliable, user-friendly option for those seeking straightforward, battery-powered smoke and carbon monoxide detection without extra complexity.

The Kidde Hardwired Smoke & Carbon Monoxide Detector is a solid choice for anyone looking to protect their home from both fire and carbon monoxide hazards with a single device. It uses photoelectric and electrochemical sensors, which are known for accurate and reliable detection of smoke and CO. Being hardwired means it’s powered directly through your home’s electrical system, so you don’t have to worry about frequently changing batteries. Plus, it comes with a 10-year lithium-ion battery backup that works even if the power goes out, offering extra peace of mind.

One of the standout features is its voice alerts that clearly announce “Fire!” or “Warning! Carbon Monoxide!” which can help you react faster in an emergency. The alarms are interconnected, meaning if one detects danger, all alarms in your home will sound to alert everyone. This is very useful in larger homes. It also includes LED indicators to show the device’s status at a glance—green for normal, amber for issues, and red for alarm conditions.

Maintenance is straightforward with a self-testing feature, but it’s recommended to test the alarm manually once a week to ensure everything is working. The device also reduces false alarms, especially those caused by cooking, which can be a common annoyance. Installation requires hardwiring into your home’s electrical system, which might be challenging if you’re not comfortable with wiring or don’t already have compatible wiring in place. Although the device is designed to last 10 years, once that period passes, you will need to replace the unit entirely. Additionally, the upper temperature limit of 100°F means it’s best suited for regular indoor environments, not extreme conditions. This Kidde detector is an excellent option for homeowners who want a dependable, low-maintenance, and feature-rich combo alarm that meets modern safety standards and offers clear alerts. It’s best suited for those willing to handle or hire professional installation to benefit from its hardwired power and interconnectivity.