What is the best smart smoke and carbon monoxide detector?

Best overall in 2026: First Alert SC5

If you’re buying a new smart smoke + carbon monoxide detector today, my top pick is the First Alert SC5 Smart Smoke & CO Alarm.

• First Alert SC5 Battery Smart Smoke and Carbon Monoxide Alarm - $129.99 (First Alert)

It’s the closest current replacement for the much-loved Google Nest Protect. It offers:

• Smoke + CO detection in one unit
• Phone alerts when you’re home or away
• Voice alerts that identify the type and location of the danger
• Wireless interconnection, so compatible alarms can all sound together
• Google Home compatibility
• UL 217 10th Edition compliance
• A 10-year limited warranty

My shortlist

• Kidde AA Battery-Powered Smart Smoke and CO Detector - $69.97 (The Home Depot)

The Kidde Smart is particularly compelling if you use Ring/Alexa. It provides real-time Ring notifications, wireless interconnection, voice alerts, and doesn't require a subscription for the basic alerts.

• X-Sense SC07-MR Interconnected Smart Smoke and CO Alarm - $129.99 (X-SENSE US)

One important caveat about Nest Protect

I wouldn't buy a Nest Protect at a premium today, despite how good it was. Google discontinued it in 2025 and First Alert's SC5 is its current successor. Google itself now provides instructions for using the SC5 as a replacement for Nest Protect.

If you tell me whether your existing detectors are battery-powered or hardwired, and whether you use Apple Home, Google Home, Alexa/Ring, or none, I can tell you exactly which model I'd buy for your house.

When choosing the best smart smoke and carbon monoxide (CO) detector, the right option depends on your existing smart home ecosystem, whether you prefer hardwired or battery-powered units, and your budget.

The top-rated choices on the market balance reliable life-saving sensors with seamless smartphone alerts:

- **Best For:** Overall smart home integration, polished design, and ease of use.
- **Why it stands out:** It features a split-spectrum sensor (detecting both fast- and slow-burning fires), a friendly human voice that tells you where the danger is, a helpful pathlight for nighttime navigation, and the ability to hush false alarms directly from your phone. Available in both battery and wired versions.[[1]](https://www.google.com/search?q=product&prds=pvt:hg,productid:14308441143687746603,catalogid:4631025932571303143,gpcid:16501895580475539389,mid:576462501990036935&ibp=oshop)

- **Best For:** A traditional alternative to Nest with modern app features and strong reliability.
- **Why it stands out:** Kidde’s smart lineup offers robust wire-free interconnectivity (if one alarm sounds, they all sound) and instant mobile notifications through their dedicated app. They are often more straightforward to integrate into standard hardwired home setups or flexible battery configurations.[](https://www.nytimes.com/wirecutter/reviews/best-smart-smoke-alarm/) [[1]](https://www.nytimes.com/wirecutter/reviews/best-smart-smoke-alarm/)[[2]](https://www.google.com/search?q=product&prds=pvt:hg,productid:13659786249019816498,catalogid:8909759822405808989,gpcid:14555490280769562235,mid:576462544680583844&ibp=oshop)

- **Best For:** Homes already running a Ring Alarm security setup.
- **Why it stands out:** Designed in partnership with Ring, this model integrates natively into the Ring app. With an optional monitoring subscription, it can directly request emergency dispatch if smoke or CO is detected while you're away.[](https://www.nytimes.com/wirecutter/reviews/best-smart-smoke-alarm/) [[1]](https://www.nytimes.com/wirecutter/reviews/best-smart-smoke-alarm/)[[2]](https://www.google.com/search?q=product&prds=pvt:hg,productid:13659786249019816498,catalogid:8909759822405808989,gpcid:14555490280769562235,mid:576462544680583844&ibp=oshop)

To help narrow down the best fit for your home, tell me:

• Do you need hardwired (120V) or battery-powered units?
• What smart home ecosystem do you primarily use (Apple Home, Google Home, Ring, or Alexa)?

Best overall: Kidde Smart Smoke + CO with Ring

For most homes in 2026, I’d buy the battery-powered Kidde Smart Smoke & CO Detector with Ring.

• Kidde AA Battery-Powered Smart Smoke and CO Detector - $69.97 (The Home Depot)

Why I like it:

• Smoke + carbon monoxide detection in one alarm.
• Wi-Fi and Ring app alerts when you're away from home.
• No Ring hub required and no subscription needed for basic alerts.
• Battery powered, so it's easy to install if you're replacing existing alarms.
• Wireless interconnection means compatible alarms can alert together.
• Voice alerts tell you what the problem is.

Consumer Reports currently rates Kidde's Smart P4010DCSCO-W among its top combination smoke/CO detectors, with a 93/100 score.

My other picks

• First Alert SC5 Battery Smart Smoke and CO Alarm - $129.99 (First Alert)

• X-SENSE XP0A-iR Smart Smoke and CO Detector - $36.99 (X-SENSE US)

• Kidde Hardwired Smart Smoke and CO Detector - $74.97 (The Home Depot)

• Best for Google Home: First Alert SC5. It's the successor to the discontinued Google Nest Protect and integrates with Google Home. The battery version is particularly convenient.

• Best value: X-Sense XP0A-iR — inexpensive, smart, battery-powered, and includes voice alerts and phone notifications.

• Best hardwired: Kidde Hardwired Smart Smoke & CO — especially if your house already has interconnected Kidde hardwired alarms.

One important caveat

The Google Nest Protect used to be my automatic recommendation, and you'll still see it recommended online. Google discontinued it in 2025, though remaining units are still being sold. Lights & Kits I wouldn't pay an inflated price for an old Nest Protect today when there are current alternatives.

Also, smart features shouldn't be the deciding factor over detection quality and proper placement. Consumer Reports emphasizes that reliable smoke/CO detection is the fundamental consideration, while WIRED notes that some smart alarms have limitations in the types of fire they detect.

Bottom line: If you want one recommendation without overthinking it, I'd get the Kidde Smart Smoke + CO battery model. If you tell me whether your existing detectors are hardwired or battery, and whether you use Alexa, Google Home, Apple Home, or Ring, I can narrow it down to the exact model I'd buy for your house.

When looking for the best smart smoke and carbon monoxide (CO) detector, the right choice depends on whether you want deep smart-home ecosystem integration, a standalone app without subscriptions, or specific ecosystem pairings like Ring.

The top-rated options on the market balance reliable life-safety sensing with modern smartphone alerts:

• Kidde Smart Smoke + Carbon Monoxide Alarm Go to product viewer dialog for this item. (Top Pick / Best Overall): Kidde's modern smart lineup is widely praised for reliable sensing that cuts down on false cooking alarms, clear voice alerts telling you the specific danger, and solid mobile app integration. It comes in hardwired or battery-operated versions and reliably sends real-time notifications when you are away from home.
• Kidde Ring Smart Smoke + Carbon Monoxide Detector (Best for Ring Users): If you already use a Ring security ecosystem, this version integrates directly with the Ring App . It supports wire-free interconnectivity (if one alarm goes off, they all do) and offers an optional professional 24/7 monitoring add-on through Ring.
• First Alert Smart Smoke & Carbon Monoxide Alarm Go to product viewer dialog for this item. (Best Runner-Up): A dependable alternative to Kidde, First Alert's smart combo units (like the SC5 series) feature straightforward app notifications, reliable photoelectric smoke and electrochemical CO sensors, and a great track record for ease of installation and daily quiet operation.
• Nest Protect Go to product viewer dialog for this item. (Best Premium Design & Ecosystem): Though it hasn't seen a hardware refresh in a while, the Nest Protect remains a fan favorite for its split-spectrum sensor (detecting both fast-flaming and slow-smoldering fires), a friendly human voice that tells you which room has the issue, and a helpful night-light feature. It integrates smoothly into the Google Home/Nest ecosystem, though it commands a higher price tag.

To help narrow down the best option for your house, tell me:

• Do you need hardwired units or battery-operated ones?
• Do you currently use a smart home ecosystem like Ring, Google Home , or Apple Home?

The [Kidde RGCUDR-RW Smart Smoke and CO Detector Go to product viewer dialog for this item. ](https://www.homedepot.com/p/Kidde-AA-Battery-Powered-Smart-Smoke-and-CO-Detector-Ring-App-Enabled-Wireless-Interconnect-Voice-Alerts-RGCUDR-RW-21033910/340313465?source=shoppingads&locale=en-US&fp=ggl&srsltid=AfmBOooSMWgNh7kmStUyhIdRhqV3A3qCNjAXoRP-pnEK6AAH56hiylcbRrk) is the best overall smart smoke and carbon monoxide detector , priced at about $70 with reliable dual-hazard sensing and mobile alerts.

Top Smart Smoke & CO Detectors

Key Features to Consider

• Kidde RGCUDR-RW : Offers wire-free interconnection and clear voice alerts that announce specific dangers like fire or carbon monoxide.
• X-Sense XP0J-iA : A budget-friendly hardwired choice with a loud siren and room-specific voice warnings.
• First Alert Onelink Safe & Sound : Combines top-tier detection with a built-in high-end Alexa speaker and AirPlay 2 support.

If you tell me your preferred smart home system (like Apple HomeKit, Google Home, or Ring) and whether you need hardwired or battery-powered units, I can narrow down the best option for your home.

If you want the best smart smoke + carbon monoxide (CO) detector for a Canadian home in 2026, my pick is the Kidde Smart Smoke & CO Alarm, particularly if you use Ring/Alexa or want a good balance of safety, smart features, and price.

Kidde Smart Smoke and Carbon Monoxide Detector

$114.00

My top choices

Why I'd choose Kidde: Current 2026 comparisons increasingly favor it as the practical choice. Consumer Reports also has multiple Kidde combination alarms among its better-performing tested models.

One important caveat

The Google Nest Protect is still arguably the most polished smart detector ever made, with particularly good voice warnings, room identification, self-testing, and smoke/steam discrimination. However, Google discontinued it in 2025, so buying one now means dealing with older stock and potentially inflated prices.

Google Nest Protect 2nd Gen Smart Smoke/Carbon Monoxide Battery Alarm

$125.00

The First Alert SC5 is the more interesting Google-oriented replacement, but current Canadian pricing is considerably higher, and its user ratings in the shopping results I found are noticeably weaker than the Kidde's.

Kidde Smart Smoke and Carbon Monoxide Detector

$114.00

First Alert SC5 Smart Smoke and Carbon Monoxide Alarm

$169.99

Google Nest Protect 2nd Gen

$125.00

First Alert Onelink Smart Smoke and Carbon Monoxide Alarm

$110.00

My recommendation: If you're buying several for your house, I'd go Kidde Smart Smoke & CO rather than paying the premium for SC5/Nest Protect.

One thing I'd verify before ordering in Canada is the Canadian ULC certification and the exact model number, because smoke/CO alarms are life-safety equipment and U.S. versions aren't necessarily appropriate for Canadian installation requirements.

If you tell me whether you use Apple Home, Google Home, Alexa/Ring, or none, I can narrow it down to the single best model for your setup and find the best Canadian price.

The Kidde Smart Smoke & Carbon Monoxide Detector Go to product viewer dialog for this item. is widely considered the best all-around smart combination alarm for most homes. With tech giants changing their focus—such as Google officially discontinuing its popular Nest Protect product line —traditional fire safety leaders like Kidde and First Alert offer the most reliable, up-to-date hardware with advanced phone connectivity.

The best options vary depending on your smart home ecosystem and how your home is wired:

Top Smart Smoke & CO Detectors

• Recognized by reviewers at Wirecutter as the top current pick.

• Uses a highly accurate photoelectric sensor paired with an electrochemical CO sensor to dramatically reduce nuisance alarms from cooking.

• Features voice alerts that call out the specific hazard and room location rather than just sounding a generic beep.

• Connects directly to Wi-Fi to push phone alerts and can wirelessly interconnect with older, non-smart Kidde alarms to update your entire house.

• Available in two tailored variations: a standard smart version for Alexa/Google Home, and an official Ring App-Enabled model (RGCUDR-RW) perfect for Ring security setups.

• The premier choice if you are transitioning away from discontinued Nest hardware or want seamless Apple HomeKit, Alexa, and Google Assistant utility.

• Provides a direct partnership framework with Google Home setups and integrates with existing smart infrastructure smoothly.

• Delivers "Precision Detection" technology to screen out kitchen steam while prioritizing real, smoldering fires.

• Offers robust voice alarms detailing exact emergency locations and comes in both hardwired or battery-operated designs.

• Rated by tech review testers as the best value configuration for full-home coverage.

• Operates on a dedicated wireless RF mesh system using a central SBS50 base station, meaning if one alarm triggers, every unit in the house sounds off simultaneously.

• Saves you money on complex electrical work via an easy screw-in battery setup that still pushes instant remote app notifications.

• Lets you safely test or silence the loud 85-decibel sounder directly through your phone app instead of climbing on chairs.

Quick Comparison

If you'd like to narrow this down, let me know:

• Do you need hardwired or battery-powered units?
• Which smart home app (Apple Home, Google Home, Alexa, or Ring) do you use the most?
• How many detectors do you need to replace?

If you want the best smart smoke + carbon monoxide detector in 2026, I’d pick the First Alert SC5 Smart Smoke & CO Alarm for a new installation.

🥇 Best overall: First Alert SC5

First Alert SC5 Battery Smart Smoke and Carbon Monoxide Alarm

$129.99

Why I like it:

• Smoke + CO detection in one unit
• Wi-Fi/app alerts when you're away from home
• Voice alerts identify the type of danger
• 10-year battery on the battery model
• Designed as the successor to Google Nest Protect and compatible with the Google Home ecosystem
• Available in both battery and hardwired versions.

The hardwired SC5 is currently about $130, while the battery version is about $130 direct from First Alert.

🥈 Best value: Kidde Smart Smoke + CO

Kidde Hardwired Smart Smoke and Carbon Monoxide Detector

$74.97

This is the one I'd choose if price matters or you're already using Kidde/Ring/Alexa. It provides app notifications, voice alerts and interconnection, and is currently around $75 for the hardwired model. Consumer Reports also ranks Kidde's smart combination detector highly.

What about Google Nest Protect?

Google Nest Protect Battery Smoke and Carbon Monoxide Detector

$149.00

It's still an excellent detector—but I wouldn't buy one new in 2026. Google discontinued Nest Protect production in 2025, so you're essentially buying remaining inventory. Existing units continue to work, but I'd rather invest in the current First Alert SC5 ecosystem for a new installation.

My ranking

One important caveat: smart connectivity shouldn't be the deciding factor for life safety. Sensor performance, proper placement, interconnection, and having the right type of smoke sensing are more important than phone notifications.

If you tell me (1) whether your existing alarms are hardwired or battery, (2) whether you use Apple Home, Google Home, Alexa/Ring, or none, and (3) how many detectors you need, I can tell you exactly which model I'd buy and how I'd set up the whole house.

The Kidde Smart Smoke & Carbon Monoxide Alarm Go to product viewer dialog for this item. is widely rated by experts as the best overall smart smoke and CO detector on the market. It features exceptionally fast photoelectric detection and robust app control without locking you into a single ecosystem.

Because Google officially discontinued the iconic Nest Protect line, the smart home landscape has shifted toward strong brand partnerships with companies like Ring and Google Home.

Top Smart Smoke & CO Detectors

Important Buying Considerations

• State & Local Laws : Check your local housing codes; many areas strictly require hardwired detectors for main living spaces and specific multi-family properties.
• Interconnectivity : Ensure your new units can interconnect. When one smart alarm detects smoke in the basement, it triggers all units in the house to sound simultaneously.
• Silence via App : Most smart models let you hush false cooking alarms from your phone. However, some models like the First Alert SC5 Go to product viewer dialog for this item. enforce a Bluetooth proximity rule requiring you to stand within 15 feet of the unit to turn it off safely.

To help narrow down the choices, tell me:

• Do you need hardwired or battery-powered units?
• Which smart home app (such as Alexa, Google Home, Ring, or Apple Home) do you use the most?
• How many detectors are you planning to replace?

If you want the best smart smoke + carbon monoxide detector in 2026, I’d pick the First Alert SC5 Smart Smoke & CO Alarm—especially if you use Google Home/Nest.

First Alert SC5 Hardwire Smart Smoke and Carbon Monoxide Alarm

$129.99

My picks

First Alert SC5 Smart Smoke & CO

$129.99

Kidde Smart Smoke & CO

$74.97

X-Sense SC07-WX Smart Smoke & CO

$79.99

Google Nest Protect

$149.00

One important caveat: I wouldn't automatically buy the SC5 despite its strong feature set. Current owner feedback is mixed, including reports of false alarms, while the Kidde has also received some complaints about reliability. www.reddit.com The SC5 is nevertheless the closest current equivalent to Nest Protect and meets UL 217/UL 2034 standards.

What I'd buy

• Starting from scratch: Kidde Smart if value and straightforward functionality matter most.
• Already invested in Google/Nest: First Alert SC5.
• Already invested in Ring: Kidde's Ring-compatible Smart Smoke + CO is particularly compelling; it provides real-time Ring notifications without requiring a subscription.
• Don't care about phone/app features: I'd actually save money and buy a high-quality 10-year sealed-battery interconnected detector instead. Smart connectivity is useful, but reliable detection and whole-home interconnection matter more.

If you tell me (1) hardwired or battery, (2) Google Home/Alexa/Ring/Apple, and (3) how many detectors you need, I can narrow it down to the best exact model and cheapest current option.