Ecobee Smart Thermostat Premium review: The best just got better
7 min readExpert’s Rating
Pros
- Beautiful industrial design
- Broad compatibility with other smart home ecosystems
- Outstanding user interface, both in the excellent app and on the device itself
- Radar-based motion detection, plus support for remote temperature/motion sensors
- Supremely easy to install and configure
Cons
- Siri support requires the presence of an Apple HomePod or HomePod mini
- Air quality sensor won’t trigger your HVAC system’s fan to circulate air
- Pricey
Our Verdict
The Ecobee Smart Thermostat Premium is beyond best in class, it’s everything a modern smart home device should be: spectacularly useful on its own, and capable of working with every other important smart home platform on the market today.
Price When Reviewed
$249.99
Best Prices Today: Ecobee Smart Thermostat Premium
Ecobee makes our long-time top pick in smart thermostats, and the all-new Ecobee Smart Thermostat Premium—the sixth generation!—delivers subtle but notable improvements along with a couple of brand-new features. This latest model manages to be even prettier than the last, with a zinc body and a glass touchscreen display that’s 50 percent larger than the previous model. Ecobee has also added new features, including an air quality sensor and onboard radar that can detect motion even around corners.
Like our previous top pick in this category, Ecobee’s new top-tier thermostat supports Apple’s HomeKit ecosystem and it has both Alexa and Siri voice assistants built in. You’ll need to choose one over the other–you can’t use both at the same time–and using the latter requires an Apple HomePod or HomePod mini in the house.
This review is part of TechHive’s coverage of the best smart thermostats, where you’ll find reviews of the competition’s offerings, plus a buyer’s guide to the features you should consider when shopping for this type of product.
As before, you’ll get one of Ecobee’s SmartSensors—for monitoring room occupancy and ambient temperature in a second location inside your home—in the box. Considering that the Ecobee Smart Thermostat With Voice Control that came to market in 2019 already has all those features, current owners will have trouble justifying an upgrade to this new model just to get an air quality sensor, better motion detection, and a larger display with a tweaked user interface.

Ecobee incorporates its smart thermostat’s wiring harness into its mounting bracket. I followed Ecobee’s advice and used plumber’s putty to plug the hole through which the wires from my HVAC system emerge in order to block any drafts that might throw off its temperature sensor.
Michael Brown/Foundry
If you’re in the market for a high-end smart thermostat, on the other hand, the Ecobee Smart Thermostat Premium should be at the very top of your list. Ecobee also announced the slightly less-sophisticated Smart Thermostat Enhanced today. It’s similarly equipped with radar and a glass touchscreen display, but it doesn’t have a built-in voice assistant and it doesn’t come with a SmartSensor, although you can add one.
We’ll review this less-expensive Ecobee model later. It costs $60 less than the top-tier model—$189.99 compared to $249.99—so buying that model and immediately adding a $50 SmartSensor doesn’t make a lot of economic sense: You’d be losing a big feature and saving just $10.
Ecobee Smart Thermostat Premium compatibility
The Ecobee Smart Thermostat Premium is compatible with virtually all HVAC systems, but the manufacturer encourages potential buyers to double-check their system with its online compatibility checker. The thermostat requires a C wire for power, but Ecobee includes a power extender kit should you remove your existing model and not find a C wire in the wall behind it. The thermostat works with single- and dual-stage furnaces, heat pumps, air conditioners, humidifiers, de-humidifiers, ventilators, and more.

The thermostat’s display confirms the wiring choices you made earlier.
Michael Brown/Foundry
I purchased a new Lennox furnace last winter and had to replace my existing smart thermostat because it didn’t support dual-stage furnaces. The installer sold me a $200 Honeywell T9, which is an excellent smart thermostat that also supports remote sensors—but it looks as though it could have been designed in the 1990s. The Ecobee is a major aesthetic improvement.
You might think the inclusion of an air quality sensor would enable the Ecobee Smart Thermostat Premium to automatically trigger your HVAC system’s fan to turn on to circulate the air in your home, pulling it through a filter to at least remove some particulate matter. It doesn’t. In fact, it doesn’t report PM levels, either. The thermostat itself shows just an icon and a one-word description of your indoor air quality—“clean,” for example.
Tap on the icon and you’ll get a rainbow-colored scale ranging from blue (clean) to red (poor). Ecobee’s app uses the same type of scale to also report crude levels of VOC (volatile organic compounds) and carbon dioxide (“low,” for example) in your home’s air, but that’s about it. It’s certainly no replacement for a dedicated air-quality sensor like the Awair Element or the Airthings Wave Plus.
Installing the Ecobee Smart Thermostat Premium

Ecobee provides a power extender kit in case your HVAC system wiring doesn’t include a C wire to power the thermostat.
Michael Brown/Foundry
Ecobee’s app steps you through every stage of the installation process, so the thermostat is an absolute breeze to install. Simply mount the wiring block to your wall, using the built-in bubble level to ensure it’s straight, pull the wires you’ve identified and labeled in a previous step through the center of the block, and shove them into the appropriate spring-loaded terminals. To be fair, Nest pioneered this style of easy installation—not to mention the concept that a thermostat can be an attractive appliance on your wall—years ago, but that doesn’t detract from Ecobee’s accomplishment here.
Once you have the thermostat installed, you deploy the included SmartSensor in another room where you spend a lot of time or in a room you know to be routinely too warm or too cold. The SmartSensor is equipped with a temperature sensor as well as a motion sensor, the latter of which will inform the thermostat whether the room is occupied and in need of temperature control. The thermostat will monitor the temperature both at the thermostat and in the room with the SmartSensor, and it will control your HVAC system to achieve a happy medium where the temperature at both locations is as close as possible to your desired target temperature. If you have troublespots in a lot of rooms within your home, you can deploy up to 32 SmartSensors, which cost about $50 each or $100 for a two-pack.
Programming the Ecobee Smart Thermostat Premium
Once you’ve installed the Ecobee Smart Thermostat Premium and SmartSensor(s), you can create a schedule with three target temperatures—the times you expect to be home, away, and asleep—for each day of the week. The thermostat will trigger your HVAC system to heat or cool (assuming you have central air) your home to maintain those temperatures. The thermostat will also take relative humidity levels into consideration to deliver a comfortable indoor climate regardless of the temperature. This works better if you have a central air conditioner, but just circulating the air using your HVAC system’s fan can help, too.

Ecobee’s excellent app makes installing the Ecobee Smart Thermostat Premium an absolute breeze. But its software didn’t anticipate my installing the thermostat in an 1890 bungalow.
Michael Brown/Foundry
The thermostat supports geofencing, and Ecobee’s app can be configured to automatically switch the thermostat to your “away” target temperature when you move outside the geographic circle you’ve established and back to your “home” target temperature when you return.
You can override the current target temperature at any time by tapping on the thermostat itself, by using the Ecobee app, by using a smart speaker, or—if you’ve set it up—by speaking directly to the thermostat. Although the Ecobee Smart Thermostat Premium itself can be configured only as an Alexa or Siri smart speaker, it is compatible with Alexa, Google Assistant, and Siri commands spoken to separate smart speakers. With an Amazon Echo, for example, you can say “Alexa, I’m cold” to increase the target temperature by triggering your furnace, or “Alexa, I’m hot” to lower the target temperature by turning on your central air conditioning. The thermostat is also compatible with Samsung SmartThings, IFTTT, and the rest of Apple’s HomeKit ecosystem.

Pins on the back side of the Ecobee Smart Thermostat Premium plug into the corresponding wiring connections on the mounting bracket. The speaker at the top allows either Alexa or Siri to talk back to you. You can play tunes on Spotify, too, but you probably won’t want to.
Michael Brown/Foundry
The Ecobee Smart Thermostat Premium is the top of its class
Speaking of smart home systems, any of Ecobee’s higher-end thermostats (Premium, Enhanced, or the Ecobee 3 lite) or the Ecobee SmartCamera we reviewed in July, 2020 can function as the hub for the Ecobee Smart Security system (we reviewed the system in August, 2020, when it didn’t include a professional monitoring option that can dispatch an emergency response to your home).
Ecobee’s monitoring service costs just $10 per month, or you can sign up for a $5-per-month plan that doesn’t include professional monitoring. Many of the limitations we discussed in that review are still relevant, but Ecobee’s plan are much better values today. Ecobee also has sophisticated door/window sensors that detect nearby motion, and a pretty-good home-security camera, the Ecobee SmartCamera, that supports Apple’s HomeKit Secure Video.
You don’t need any subscription at all to get the full benefit of the Ecobee Smart Thermostat Premium. It’s the prettiest, most sophisticated smart thermostat on the market today. It can supplement your smart speakers—or replace one of them—or it can be controlled by any of them. It’s compatible with virtually any HVAC system apart from high-voltage heaters, it’s Energy Star certified to conserve energy, and it enables you to take advantage of money-saving incentives—such as time-of-use rates and Community Energy Savings programs—that might be offered by your local utility. We dig it.
Ecobee Smart Thermostat Premium review: The best just got better