For renters and apartments
The Best Smart Smoke & CO Detectors for Renters (2027)
The best renter-friendly smart alarms for 2027: battery models that add phone alerts without wiring or landlord projects.
The short answer
Renters should start with the X-Sense XS0B-MR for smoke alerts in 2027 and add the Kidde Smart CO Alarm where fuel appliances live.
Our top picks at a glance
- X-Sense XS0B-MR121 Smart Smoke Detector with Base StationA Wi-Fi smoke alarm kit with voice location alerts and an SBS50 base station.Cheapest phone alerts
- Google Nest Protect (2nd Gen)The premium split-spectrum alarm that speaks, self-tests, and lights your path.Best battery premium
- Kidde Smart CO AlarmPlug-in smart CO detection with battery backup and app alerts for furnace rooms.Best plug-in CO add-on
- First Alert SCO500B Wireless Interconnected Smoke & CO AlarmA battery combo alarm that wirelessly interconnects up to 16 units, with voice and location alerts.Battery combo with wireless interconnect
- First Alert Z-Wave Smoke & CO Alarm ZCOMBOThe hub-home combo alarm: Z-Wave alerts through Ring Alarm or SmartThings, no Wi-Fi needed.Best for hub homes
- X-Sense SC07-W Wireless InterconnectedInterconnected combo alarms that all sound together, with a 10-year sealed battery.Best interconnected battery set
- X-Sense SC07The standalone SC07 combo: LCD CO display and 10-year battery, base for interconnected sets.Best LCD combo value
What owners report
Synthesized from recurring themes in long-term owner feedback.
Most praised
- Battery and plug-in picks here install with no wiring, so a rental gets smart coverage in an afternoon
- Interconnected sets move with the tenant at lease end instead of staying behind in the ceiling
Common complaints
- Renters cannot always get permission for hardwired swaps, limiting them to battery models
- A base station or hub adds one more small box that landlords eye suspiciously
The picks, ranked
Every product in this lineup was picked for this use case, ranked with our strongest choices first. If a product from the wider category does not genuinely fit this scenario, it is not listed here.
| # | Product | Award | Sensors | Power | Connectivity | Alerts | Model |
|---|---|---|---|---|---|---|---|
| 1 | X-Sense XS0B-MR121 Smart Smoke Detector with Base Station | Cheapest phone alerts | Photoelectric smoke only | Battery powered alarms; base station plug-in | Wi-Fi via SBS50 base station, wireless interconnect | Voice location alerts, app notifications | XS0B-MR (kit XS0B-MR121) |
| 2 | Google Nest Protect (2nd Gen) | Best battery premium | Split-spectrum smoke, CO, humidity, temperature, occupancy | Battery (6 AA lithium) or hardwired 120V model | Wi-Fi, Thread interconnect between Protects | - | - |
| 3 | Kidde Smart CO Alarm | Best plug-in CO add-on | Electrochemical carbon monoxide | 120V plug-in with battery backup | Wi-Fi 2.4GHz | - | - |
| 4 | First Alert SCO500B Wireless Interconnected Smoke & CO Alarm | Battery combo with wireless interconnect | Photoelectric smoke, electrochemical CO | Battery, 2 AA (included) | - | - | SCO500B |
| 5 | First Alert Z-Wave Smoke & CO Alarm ZCOMBO | Best for hub homes | Photoelectric smoke, electrochemical CO | 2 AA batteries | Z-Wave (hub required) | - | - |
| 6 | X-Sense SC07-W Wireless Interconnected | Best interconnected battery set | Photoelectric smoke, electrochemical CO | 10-year sealed lithium battery | RF wireless interconnect (868/915MHz by region) | - | - |
| 7 | X-Sense SC07 | Best LCD combo value | Photoelectric smoke, electrochemical CO with LCD | 10-year sealed lithium battery | RF interconnect capable; no direct Wi-Fi | - | - |
Cheapest phone alerts
X-Sense XS0B-MR121 Smart Smoke Detector with Base Station
A Wi-Fi smoke alarm kit with voice location alerts and an SBS50 base station.
A compact Wi-Fi smoke alarm kit with a base station that moves with you between rentals. Pair a CO alarm for full coverage.
Strengths
- Wi-Fi phone alerts through the included SBS50 base station
- Voice alerts name the location across 17 preset locations
- Wireless interconnect: when one alarms, the set sounds together
- Test and silence from the X-Sense app
Limitations
- Smoke only; no CO sensor
- Phone alerts route through the base station, not direct Wi-Fi
- Base station needs its own outlet and 2.4GHz Wi-Fi
| Sensors | Photoelectric smoke only |
|---|---|
| Power | Battery powered alarms; base station plug-in |
| Connectivity | Wi-Fi via SBS50 base station, wireless interconnect |
| Alerts | Voice location alerts, app notifications |
| Model | XS0B-MR (kit XS0B-MR121) |
Best for: Apartments and homes needing phone smoke alerts cheaply; smoke only, pair with a CO alarm.
Skip if: You need CO sensing in the same unit; the XS0B-MR is smoke only.
Best battery premium
Google Nest Protect (2nd Gen)
The premium split-spectrum alarm that speaks, self-tests, and lights your path.
The battery Protect needs no wiring and delivers the full voice, pathlight, and self-test experience, then unscrews at move-out.
Strengths
- Split-spectrum photoelectric sensor reduces cooking false alarms
- Voice alerts name the room and threat before the siren
- Silence from the app when you are nearby
- Nightly Promise self-check and a pathlight that glows on motion
Limitations
- Premium price multiplies across a whole home
- 10-year sealed life means full unit replacement at expiry
- Google Home migration left some legacy Nest app users frustrated
| Sensors | Split-spectrum smoke, CO, humidity, temperature, occupancy |
|---|---|
| Power | Battery (6 AA lithium) or hardwired 120V model |
| Connectivity | Wi-Fi, Thread interconnect between Protects |
| Lifespan | 10 years, CO sensor rated 10 years |
| Certification | UL 217 and UL 2034 listed |
Best for: Homes wanting the best app alerts, voice alarms, and nuisance-alarm intelligence.
Skip if: Budget matters; Protect costs several times a basic smart alarm per room.
Best plug-in CO add-on
Kidde Smart CO Alarm
Plug-in smart CO detection with battery backup and app alerts for furnace rooms.
Plug-in CO protection for the furnace-adjacent outlet landlords rarely cover well, with app alerts and zero installation.
Strengths
- Dedicated electrochemical CO sensing with digital display lineage
- Plug-in power with battery backup rides out outages
- Wi-Fi app alerts for CO events away from home
- Peak-level memory helps diagnose intermittent furnace issues
Limitations
- CO only; pair with smoke alarms for full coverage
- Occupies an outlet near the floor or appliance
- Smart features depend on Kidde app availability in your region
| Sensors | Electrochemical carbon monoxide |
|---|---|
| Power | 120V plug-in with battery backup |
| Connectivity | Wi-Fi 2.4GHz |
| Lifespan | 10-year alarm life |
| Certification | UL 2034 listed |
Best for: Homes adding connected CO coverage near fuel-burning appliances.
Skip if: You need smoke sensing too; this is a CO-only device by design.
Battery combo with wireless interconnect
First Alert SCO500B Wireless Interconnected Smoke & CO Alarm
A battery combo alarm that wirelessly interconnects up to 16 units, with voice and location alerts.
The SCO500B is battery powered and mounts with no wiring, so a renter can still have a true combo alarm, and units interconnect wirelessly if the rental has more than one floor.
Strengths
- Wireless interconnect: when one alarm sounds, all sound, across up to 16 compatible units
- Voice alarm announces the threat type and its programmed location
- Photoelectric smoke sensor reduces cooking nuisance alarms, with an electrochemical CO sensor
- Battery powered with a side-load battery drawer, so no electrician and easy swaps
Limitations
- No app or phone alerts; the interconnect network is local only
- Runs on replaceable AA batteries rather than a sealed 10-year pack
- 7-year limited warranty is shorter than 10-year class rivals
| Sensors | Photoelectric smoke, electrochemical CO |
|---|---|
| Power | Battery, 2 AA (included) |
| Interconnect | Wireless RF, up to 16 compatible units |
| Alarm | 85 dB with voice and location |
| Dimensions | 5.13 x 5.13 x 2.8 in |
| Model | SCO500B |
Sources: First Alert product data, CamelCamelCamel, Amazon listing data
Best for: Renters and multi-story homes wanting whole-home sounding without hardwiring.
Skip if: You want phone app alerts; this network is alarm-to-alarm RF, not cloud-connected.
Best for hub homes
First Alert Z-Wave Smoke & CO Alarm ZCOMBO
The hub-home combo alarm: Z-Wave alerts through Ring Alarm or SmartThings, no Wi-Fi needed.
The ZCOMBO is battery powered and mounts anywhere, the renter-friendly route into Ring Alarm or SmartThings alerts without touching the landlord's wiring.
Strengths
- Integrates alarms into Ring Alarm and SmartThings automations
- Battery powered, mounts anywhere without wiring
- Photoelectric smoke plus electrochemical CO in one unit
- Hub alerts work even though the alarm itself is not Wi-Fi
Limitations
- Requires a compatible Z-Wave hub for any smart feature
- No voice or room-naming alerts
- Not a primary Ring Alarm monitored sensor in all configurations, check your plan
| Sensors | Photoelectric smoke, electrochemical CO |
|---|---|
| Power | 2 AA batteries |
| Connectivity | Z-Wave (hub required) |
| Lifespan | 7 to 10 year sensor life by model date |
| Certification | UL 217 and UL 2034 listed |
Best for: Ring Alarm and SmartThings homes wanting alarms inside the security system.
Skip if: You have no Z-Wave hub; this alarm has no standalone app.
Best interconnected battery set
X-Sense SC07-W Wireless Interconnected
Interconnected combo alarms that all sound together, with a 10-year sealed battery.
Battery powered with a 10-year sealed cell and nothing wired, the SC07-W set covers a whole rental and unscrews clean at move-out.
Strengths
- Wireless interconnect: one alarm triggers all units
- 10-year sealed lithium battery, zero battery chores
- Photoelectric smoke plus electrochemical CO
- Multi-packs price whole-home coverage reasonably
Limitations
- Remote phone alerts require the optional base station ecosystem
- Brand app ecosystem is younger than Nest or Kidde
- No voice location announcements
| Sensors | Photoelectric smoke, electrochemical CO |
|---|---|
| Power | 10-year sealed lithium battery |
| Connectivity | RF wireless interconnect (868/915MHz by region) |
| Lifespan | 10 years |
| Certification | UL 217 and UL 2034, EN standards by region |
Best for: Multi-story homes needing whole-house sounding without hardwiring.
Skip if: You want phone alerts out of the box; interconnect is RF, app needs the SBS50 base on supported setups.
Best LCD combo value
X-Sense SC07
The standalone SC07 combo: LCD CO display and 10-year battery, base for interconnected sets.
The SC07 is the battery standalone combo: 10-year sealed battery, no installation beyond the mount, and a live CO readout in PPM that renters rarely get from landlord-installed units.
Strengths
- LCD shows real-time CO concentration in PPM
- 10-year sealed battery and sensor life
- Can wirelessly link with SC07-W units in mixed sets
- Lower price than the pure interconnect model
Limitations
- Standalone unit has no direct phone app alerts
- No voice announcements
- App ecosystem requires stepping up to base-station models
| Sensors | Photoelectric smoke, electrochemical CO with LCD |
|---|---|
| Power | 10-year sealed lithium battery |
| Connectivity | RF interconnect capable; no direct Wi-Fi |
| Lifespan | 10 years |
| Certification | UL 217 and UL 2034 by regional model |
Best for: Budget combo coverage and the starting unit for an X-Sense interconnected system.
Skip if: You want phone alerts from this unit alone; smart alerts need interconnected base or Wi-Fi siblings.
Questions, answered
Can renters replace landlord alarms?
Rules vary; generally you may add your own alarms but must not disable provided ones. Keep landlord units in place and supplement them.
Do battery smart alarms meet code?
Many jurisdictions accept listed 10-year sealed battery alarms; hardwired requirements apply to new construction. Check local code before relying on any single model.
What about cooking false alarms in small apartments?
Place photoelectric alarms at the recommended distance from cooking appliances and prefer models with hush features and smart sensing, like Protect or the Onelink line.
Can I take interconnected sets to my next home?
Yes, battery RF sets move intact. Re-test interconnect after reinstalling in the new layout.