Smart thermostats deliver the most measurable savings of any smart home device — typically $100-150/year in heating/cooling reduction for the average home. The two dominant brands in 2026 are Ecobee (with the SmartThermostat Premium at $249) and Google Nest (with the Nest Thermostat 3rd Gen at $129). Both work with most HVAC systems. Both have proven track records. They differ meaningfully in features, ecosystem, and price.
After 2 months running both in different rooms of the same house (Ecobee in main living area, Nest in master bedroom), here's the comparison. Ecobee SmartThermostat Premium, Nest Thermostat 3rd Gen, and the head-to-head page.
The big feature gap
Ecobee SmartThermostat Premium includes a built-in remote room sensor (SmartSensor) in the box. The sensor monitors temperature in another room and the system can use that data for "Follow Me" scheduling — adjusting heating/cooling based on which room is occupied. Additional sensors are $99 for a 2-pack.
Nest Thermostat 3rd Gen has temperature sensors built into the thermostat unit only. Remote sensors are available but sold separately ($39 each). For multi-room temperature averaging, you need to buy extras.
Most multi-floor or multi-zone homes benefit significantly from remote sensors. Ecobee includes one; Nest doesn't.
Learning vs scheduling
Nest Thermostat 3rd Gen uses Google's "auto-learning" — it observes your manual adjustments for the first week or two and builds a schedule automatically. For users who don't want to set schedules, this is genuinely useful. After 2 weeks the Nest knew our occupancy pattern (away weekdays 8a-6p, home evenings/weekends) and adjusted accordingly.
Ecobee uses traditional manual scheduling plus "eco+" features — geofencing (away when phone leaves home), occupancy sensing via SmartSensor, and adaptive schedule suggestions. More configurable but requires setup.
For users who want set-and-forget: Nest wins. For users who want granular control and configurability: Ecobee wins.
Voice assistants
Nest works with: Google Assistant (deep integration), Amazon Alexa. NO Siri.
Ecobee works with: Amazon Alexa (built-in mic and speaker on the SmartThermostat Premium — it functions as a full Alexa device), Apple HomeKit (full Siri voice control), Google Assistant (basic).
For Apple ecosystem users, Ecobee is the only choice between these two. For Google ecosystem users, Nest is the better-integrated choice.
Energy savings reporting
Both: monthly home energy reports via app. Both: identify high-usage periods, suggest savings tweaks.
Ecobee's reports are more detailed — broken down by HVAC stage usage (heat/AC/fan), outdoor temperature correlation, and per-room temperature data from sensors. Nest's reports are simpler and more visual.
For users who want to optimize savings: Ecobee's data is more actionable. For users who just want general feedback: Nest is sufficient.
App quality
Ecobee app: feature-rich, occasionally cluttered. Lots of options to drill into. Reliable iOS and Android.
Google Home app (controls Nest): cleaner UI, simpler. Less granular control. Reliable iOS and Android.
For users who like minimalism: Nest via Google Home. For users who want comprehensive control: Ecobee.
Display and physical design
Ecobee SmartThermostat Premium: 3.5" touchscreen with full-color display, glass front. Looks premium on the wall.
Nest Thermostat 3rd Gen: 2-inch round LED display with rotating outer ring (the original Nest aesthetic). Also looks premium but smaller and simpler.
Both are wall-mountable. Both attractive. Personal preference.
HVAC compatibility
Both: work with most 24V HVAC systems (forced air heat, AC, heat pumps, hydronic). Both: include C-wire requirements for power; both provide power adapters if your wiring lacks a C-wire ($25 add-on for Nest, included for Ecobee).
If your home has a particularly old or unusual HVAC system (some heat pumps with high-voltage humidifiers, multi-stage zoned setups), check compatibility for both before buying — neither is universal.
Setup difficulty
Nest installation: simpler. Single wire-strip-and-clamp design. Most DIY users finish in 20-30 minutes.
Ecobee installation: slightly more complex due to more wire options and the power adapter. Most DIY users finish in 30-45 minutes.
For first-time installers, Nest is the easier project.
Price reality
Ecobee SmartThermostat Premium: $249 retail. Frequently $199-219 on promotions. Includes 1 SmartSensor.
Nest Thermostat 3rd Gen: $129 retail. Frequently $99-119 on promotions. No included sensors (extras $39 each).
For a fair feature-equivalent comparison: Ecobee $249 vs Nest $129 + 2 sensors ($78) = $207. Within $40 of each other.
Verdict by buyer type
Get the [Ecobee SmartThermostat Premium](/product/smart-thermostats/ecobee-smartthermostat-premium) if: you have a multi-floor or multi-zone home that benefits from remote sensors, you want Apple HomeKit / Siri support, you want detailed energy reports, you appreciate the included Alexa-speaker functionality (you can use it for music, queries, intercom), or you want maximum configurability.
Get the [Nest Thermostat](/product/smart-thermostats/nest-nest-thermostat) 3rd Gen if: you have a single-floor home or single-zone HVAC, you want set-and-forget auto-learning, you have Google ecosystem (Pixel phone, Nest cameras, Google Assistant), you prefer simpler app and minimal configuration, or you want to save $50-100 versus Ecobee.
Both deliver the energy savings that justify smart thermostats. The choice comes down to ecosystem and how granular you want the controls.