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, at the grocery store or on vacation — 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 — both heating and cooling — 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 of the best smart thermostat from the pack. Here's a list of smart thermostats we've tested recently:
Note that the products discussed here are independently chosen by our editors. CNET may get a share of the revenue if you buy anything featured on our site.
The Ecobee SmartThermostat is 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 Wi-Fi thermostat is also a great option.
Now playing: Watch this: Ecobee's new thermostat is part Alexa speaker
The Honeywell Lyric T5 costs $150. I know, that isn't exactly affordable. But it's a solid price for a Wi-Fi 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).
The Ecobee SmartThermostat has a built-in Alexa speaker. Ask the speaker for the temperature, 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 Wi-Fi programmable thermostat also offers integration with Google Assistant and Siri, so if you have a Google-Assistant-enabled smart speaker or a HomePod, you can control it with Google Assistant and Siri commands.
The Ecobee mobile 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 mobile app. And that's important because the mobile app is 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).
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: