Smart thermostats do more than automate a fixed heating and cooling schedule. These app-enabled devices make it possible to adjust your thermostat whether you’re on the couch, on vacation or at the grocery store — anywhere your phone is connected to a cellular or a Wi-Fi network. Many of them also work with Alexa, Google Assistant and Siri now too, giving you yet another way to adjust your thermostat without having to stand directly in front of it.
Some smart thermostats also use sensors to determine if you’re home or away and automatically change the temperature for you. Others rely on a geofencing radius — once you get a certain distance from your home, they switch to away mode and then back to home mode when you return.
To accompany these modern features, a lot of connected thermostats boast innovative designs. From a rounded shape to a responsive touchscreen, today’s thermostats look different than they used to.
Let’s explore the available options model-by-model. We’ll highlight what makes each model stand out from the rest and ultimately pick an overall winner from the pack.
Best smart thermostats
Let’s get into the specifics. Here’s a list of smart thermostats we’ve tested recently:
- Ecobee3 Lite
- Emerson Sensi
- Emerson Sensi Touch
- Honeywell Lyric
- Honeywell Lyric T5
- Johnson Controls GLAS
- Lux Geo
- Lux Kono
- Nest Learning Thermostat
- Nest Thermostat E
Best value: Honeywell Lyric T5
The Honeywell Lyric T5 costs $150. I know, that isn’t exactly affordable. But it’s a solid price for a smart thermostat. Many models, including the Nest Learning Thermostat and the Ecobee4 cost $249. This makes the T5 a great ‘budget’ option that works with Alexa, Google Assistant and Siri (via Apple HomeKit).
Best voice control: Ecobee4
The Ecobee4 thermostat has a built-in Alexa speaker. Ask the speaker for the current weather forecast, to tell you a joke — and to adjust the temperature of your smart thermostat, all without needing a separate Alexa speaker. This device also works with Google Assistant and Siri, so if you have a Google-Assistant-enabled smart speaker or a HomePod, you can also control it with Google Assistant and Siri commands.
Best design: Nest Learning Thermostat
I hold that the $249 Nest Learning Thermostat is still the best looking smart thermostat out there. Its rounded design harkens back to old-school thermostats, but it has a modern look that fits in with nearly any home decor. The $169 Nest Thermostat E looks nice too, but it has more plastic components that aren’t as appealing as the Learning Thermostat’s stainless steel.
Best app: Ecobee
The Ecobee app is straightforward and easy to navigate. That sounds simple enough, but so many apps make it tough to find the specific setting or feature you’re looking for. Not so with Ecobee’s app. And that’s important because it’s one of the main ways to interact with your thermostat when you aren’t standing directly in front of it (aside from using a voice command).
Best overall: Ecobee4
Ecobee’s Ecobee4 is still my favorite smart thermostat available today. Yes it’s expensive at $249, but it has the performance and features to back it up — especially if you want to talk to Alexa without having to buy an Amazon Echo If you don’t want or need an Alexa speaker, the $169 Ecobee3 Lite is also a great option.
Testing a thermostat
Let’s talk about testing. Smart thermostats start with the installation. Installations can vary widely from thermostat to thermostat and HVAC system to HVAC system, but there are some basic steps required for each thermostat installation. As always, consult a professional installer if you have any questions about the process. Here are the general steps:
- Turn off power to your thermostat at the circuit breaker
- Remove the old thermostat
- Install the thermostat’s baseplate with the included screws
- Attach the wires to the wire terminals
- Snap on the faceplate
- Turn on power at the circuit breaker
Was the thermostat especially difficult to install? If so, why? Certain models require a C-wire, for example, which can complicate the installation if you don’t have one. Not sure what a C-wire is? Start here.
From there, I move on to the app. Every smart thermostat has one. I download the app and create an account if I don’t already have one. Then I configure the thermostat following the steps in the app. This usually means connecting to the local Wi-Fi network, giving your thermostat a name like ‘Hallway’ or ‘Bedroom’ and then you can start using your thermostat.
How well does the app work? Is it easy to navigate to the settings you need? Is it simple to create a schedule or enable geofencing? This factors into the thermostat’s usability score, along with how simple the thermostat hardware itself is to control manually.
I also test any smart home integrations, especially voice-enabled ones you can access through Alexa, Google Assistant or Siri. Most connected thermostats work with at least one voice assistant and some, like the Ecobee3 Lite and Ecobee4, work with all three. Do the voice commands flow naturally, like they would in an actual conversation? Did the thermostat actually adjust the temperature according to your commands?
All of these things determine a smart thermostat’s overall score and how likely I am to recommend it.