Google Nest Protect Smoke + CO Alarm

Quick verdict

The Nest Protect is the most polished smart smoke alarm ever made - voice alerts, wireless interconnect, and the pathlight are useful. But Google has discontinued it, and its Home Assistant story is weak: the official Nest integration does not support Protect, so you need an unofficial community integration over Google's cloud. Local-control advocates should look at a Z-Wave or Zigbee/Matter smoke alarm instead, though note that First Alert's ZCOMBO-G is itself no longer sold new: the current model is the SMCO410, which keeps the Z-Wave Plus radio and adds a sealed 10-year battery.

Standout: Wireless interconnect with voice alerts that tell you the type and location of danger across every Nest Protect in your home.

Notes last checked May 31, 2026.

Compatibility snapshot

Why it stands out

• excellent build quality with voice alerts that tell you what the danger is and where
• multiple Nest Protects interconnect wirelessly so all alarms sound when one detects smoke or CO
• pathlight feature illuminates hallways when it detects motion at night

Reasons to hesitate

• Google has discontinued the Nest Protect - increasingly hard to buy new
• the official Google/Nest integration does NOT support Nest Protect; only an unofficial community integration (undocumented API) works
• premium price for a smoke alarm, significantly more expensive than alternatives

Best for

• existing Nest Protect owners who want to surface alerts in Home Assistant via the community integration
• buyers who prioritize industrial design and voice alerts over local control

Avoid if

• local control and privacy are priorities for you
• you want a currently-supported product with deep Home Assistant integration

Privacy and local-control notes

Highly cloud-dependent for smart features. Nest collects usage data and sends it to Google servers. The device functions as a basic smoke alarm offline, but all smart notifications and integrations require cloud connectivity.

Home Assistant support: supported · integration path: ha-nest-protect (unofficial community; the official Nest/SDM integration does NOT support Protect).

Buying reality check

Price notes: Premium pricing. Now discontinued by Google (existing units remain supported); available while stock lasts in battery and wired models.

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