Data from Amazon and official First Alert and Shelly sites.
2026 verdict
Shelly Plus Smoke Alarm edges out First Alert SC5 Battery Smart Smoke & CO Alarm in 2026, led by price, rating, and connectivity. Its clearest strengths are price, rating, and connectivity, and it still looks stronger on integrations and built-in light. First Alert SC5 Battery Smart Smoke & CO Alarm still makes sense if warranty, sensors, and alerts is your priority, but most buyers should still lean toward Shelly Plus Smoke Alarm. As a general recommendation, Shelly Plus Smoke Alarm comes out on top.
| Feature | First Alert SC5 Battery Smart Smoke & CO Alarm | Shelly Plus Smoke Alarm | Winner |
|---|---|---|---|
| Price | $129.98 | €39.95 | Shelly Plus Smoke Alarm |
| Rating | 3.5 | 4.3 | Shelly Plus Smoke Alarm |
| Warranty | 10 years | 3 years | First Alert SC5 Battery Smart Smoke & CO Alarm |
| Connectivity | 2.4 GHz WiFi | 2.4 GHz WiFi, Bluetooth | Shelly Plus Smoke Alarm |
| Integrations | Google Home | Google Home, Alexa, Samsung SmartThings, Home Assistant | Shelly Plus Smoke Alarm |
| Sensors | Smoke, CO | Smoke | First Alert SC5 Battery Smart Smoke & CO Alarm |
| Alerts | Fire Alerts, CO Alerts, Low Battery Alerts | Fire Alerts, Low Battery Alerts | First Alert SC5 Battery Smart Smoke & CO Alarm |
| Built-in Light | NO | YES | Shelly Plus Smoke Alarm |
| Steam Check | YES | NO | First Alert SC5 Battery Smart Smoke & CO Alarm |
| Screen | NO | NO | Tie |
| Built-in Siren | YES | YES | Tie |
| Tests Itself | NO | NO | Tie |
- + Warranty: 10 years
- + Sensors: Smoke, CO
- + Alerts: Fire Alerts, CO Alerts, Low Battery Alerts
- - Price: $129.98 vs €39.95
- - Rating: 3.5 vs 4.3
Winner
25% OFF
€39.95
€53.43
- + Price: €39.95
- + Rating: 4.3
- + Connectivity: 2.4 GHz WiFi, Bluetooth
- - Warranty: 3 years vs 10 years
- - Sensors: Smoke vs Smoke, CO
Frequently Asked Questions (FAQ)
Which is better overall: First Alert SC5 Battery Smart Smoke & CO Alarm or Shelly Plus Smoke Alarm?
Shelly Plus Smoke Alarm has the stronger overall profile in this comparison, especially for price, rating, and connectivity.
What is the biggest difference between First Alert SC5 Battery Smart Smoke & CO Alarm and Shelly Plus Smoke Alarm?
Price is one of the clearest differences: First Alert SC5 Battery Smart Smoke & CO Alarm lists $129.98, while Shelly Plus Smoke Alarm lists €39.95.
Which one looks better on price?
First Alert SC5 Battery Smart Smoke & CO Alarm is listed at $129.98, while Shelly Plus Smoke Alarm is listed at €39.95. Shelly Plus Smoke Alarm (better spec).
Who should buy First Alert SC5 Battery Smart Smoke & CO Alarm?
Choose First Alert SC5 Battery Smart Smoke & CO Alarm if your priority is warranty and sensors and that matters more than price.
Who should buy Shelly Plus Smoke Alarm?
Choose Shelly Plus Smoke Alarm if your priority is price and rating and that matters more than warranty.
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