10 Best Smoke Detector Carbon Monoxide Detectors Combo 2026 in the United States

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 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 Kidde Hardwired Smoke & Carbon Monoxide Detector is a solid choice if you're looking to protect your home with one device that covers both smoke and carbon monoxide hazards. It uses photoelectric and electrochemical sensors, which are reliable at detecting smoke and CO respectively. Being hardwired means it connects directly to your home’s electrical system but also includes a 10-year lithium battery backup, so it keeps working even during power outages without the hassle of frequent battery changes. The alarms are loud (85 decibels) and include clear voice alerts that say “Fire” or “Warning, Carbon Monoxide,” which can be easier to understand in an emergency compared to just a beep. The detectors also have LED lights to add visual cues.

Installation suits those comfortable with wiring or who can hire a professional, as hardwired units require more setup than battery-only models. These alarms have a lifespan of 10 years, matching most modern safety standards, meaning you won’t need to replace them often. The 3-pack offers good value for covering multiple rooms.

One minor downside is that the unit’s upper temperature rating is 100°F, so placing it in very hot areas might not be ideal. Also, while the hardwired power source provides reliability, some users might prefer a simpler battery-only option if they want easy DIY installation. This Kidde combo detector is well-suited for homeowners looking for dependable dual hazard detection with voice alerts and long-lasting power, especially if professional installation is an option.