The 4 Best Smart Thermostats of 2025

The Ecobee Smart Thermostat Premium kept my 1,500-square-foot, three-level house more consistently comfortable than any other thermostat we tested, likely because the Ecobee Premium is able to use indoor humidity data when automatically adjusting the temperature set point (more on that below). It comes with a terrific remote sensor that detects temperature, to help balance comfort throughout your home, as well as presence, so you can have your HVAC ensure that the room you’re occupying is at your preferred temperature. The thermostat also has a mic and a built-in smart speaker, which enables voice control. The Ecobee Premium uses AI to figure out when to heat and cool, and it has stylish glass and metal hardware. Ecobee also has a best-in-class privacy policy, and notably, the company still provides tech support for even its earliest models.

Installation was reasonably straightforward but not perfect. A phone app walked me through the process step-by-step. Our setup was simplified because it already had a “C” wire, or common wire, which is a constant power source required by most modern thermostats. The Ecobee Premium includes a C-wire adapter for those systems that don’t have a C wire already. If you are uncomfortable fiddling with tools and wires, it might be smart to hire a qualified installer—you can find one on the Ecobee website.

Ecobee learns your schedule and your home. As with the Google Nest Learning Thermostat, the idea with the Ecobee Premium is that you set your preferred temperature manually, then Ecobee’s Schedule Assistant learns your behavior over time. If it sees that you could save more energy, it will suggest a better Schedule for you, but those changes don’t happen automatically—you have to make them yourself. Ecobee’s webpage gives you insights and real-time updates about your energy usage and thermostat set points (which Nest doesn’t offer).

Similarly, Ecobee also learns over time how long it takes to heat or cool your house, a process it calls Smart Recovery. It then uses that info to adjust when it kicks on so that your house is at your preferred temperature right at your preferred time.

The Eco+ setting may be the most valuable feature. Yet, an Ecobee representative says it’s the most underused, too. When you enable Eco+ mode, the thermostat considers a room’s humidity when automatically adjusting the temperature setting to secure greater efficiency and savings (note that the Nest also uses indoor humidity to calculate the best temperature setting). Here’s a little trick of human physiology: The higher the humidity in a room, the warmer the air feels. The Ecobee calculates how the temperature feels (similar to how weather websites tell you what the outdoor temperature “feels like”). Then, it takes advantage of that phenomenon whenever possible by heating just a little less in winter and cooling a little less in summer. The result is that the Ecobee is able to eke out maximum energy savings without any sacrifice in comfort.

The room sensors are excellent. One remote temperature and presence SmartSensor is included with the Premium. You’re meant to place it in another part of your house to help even out heating and cooling across your home. Additional sensors can be bought separately, depending on your needs.

These 1.75-inch, squarish sensors can not only help even out temps throughout a house but also detect when there is a person present and, if you like, prioritize the comfort settings in that room. So if you are in a room that runs hotter than the rest of the house, Ecobee will let the temperature drop throughout that heating zone until the warmer room you’re in is at your desired temperature. (The same process works with cooling, as well.) The unobtrusive sensors come with little magnetic stands for setting them on a shelf, table, or bookcase, but there are a variety of mounting options.

Ecobee Premium is like an Amazon Echo Dot on your wall. The Premium is the only current smart thermostat with a built-in smart speaker, and the audio quality and microphone responsiveness are on a par with those of the third-generation Amazon Echo Dot. All of the standard Echo speaker features are here, including Alexa Calling, Messaging, and Drop In, so you can use your thermostat as you would an old-school intercom system. Notably, while you can listen to Spotify directly through it, you can’t use it as a part of an Alexa multiroom music setup.

You can also enable the speaker to work with Siri to accept voice commands directly and to act as an AirPlay speaker, including as part of a multiroom audio system. We haven’t tested that feature yet, but we will update this review when we do (Ecobee explains the setup process here).

If you aren’t interested in having a smart assistant like Alexa (or Siri) in your home, you can completely disable it in the settings of the Ecobee app.

The Ecobee Premium is all metal and glass. This adds a level of polish that is important to some device owners (even if it makes no difference in performance). The display shows the temperature, the weather outside, the time, and indoor air-quality scores. When indoor air quality drops, the Ecobee sends an alert telling you to open a window or turn on an air purifier. Ecobee was purchased in 2021 by Generac, an auxiliary generator company, and the thermostat can now display the operating status of the company’s generators, although it can’t control them.

Don’t need built-in Alexa or an included remote sensor? You might consider the more basic Ecobee Smart Thermostat Enhanced, which doesn’t include the speaker and mic, remote sensor, or air-quality monitor. It also has more modest plastic housing. Beyond those differences, it runs an HVAC system just as well as the Premium model.

Flaws but not dealbreakers

• The Ecobee Premium’s installation is like that of most thermostats, though we did experience connection issues at first. There are also some obscure technical questions during setup that may require research (“How is your reversing valve energized?”).
• We experienced voice-command issues both with Siri and when using the built-in Alexa. (This may be a problem specific to me—no voice recognition of any kind has ever worked well for me.)
• If Alexa is enabled, by default you will receive spoken notifications and reminders about Amazon purchases, and many may find this intrusive. One time, Alexa gave a spoken reminder through the thermostat’s speaker to rate a recent purchase. I turned that setting off in the privacy section of the Alexa App.
• Customer support is lacking. A Wirecutter editor was troubleshooting an Ecobee that wouldn’t connect to the internet, and they waited 30 minutes on hold before giving up and leaving a number for a callback, which came hours later. The technician was unable to solve the issue and said they would investigate and call back, but they never did. A week later, a summary email arrived, closing the case with no solution. (The thermostat fixed itself in the end.)

How the Ecobee Premium has held up

The author of this guide, Roy Furchgott, has rotated the Ecobee Premium in with other test thermostats since we first made it a pick. And after an initial hiccup, he remains very pleased. “The Ecobee initially changed temperatures too drastically in an attempt to save energy, which backfired, causing my heat-pump-based system to run almost nonstop. After manually fine-tuning it to correct this issue, and nearly a year and a half of testing since then, it has chugged along without incident. On top of being trouble-free, its looks have drawn admiring comments from visitors.”

Privacy snapshot

• Ecobee collects information pertinent to the functioning of the thermostat. During installation, it asks for your name, email, home address, home age, the number of floors in your home, and the number of occupants.
• Geofencing technology requires tracking your phone location. You can opt out in the Ecobee app’s settings.
• Ecobee does not share customer data with third parties.
• You can read the full privacy policy here.