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A good smart thermostat is a necessary addition to any smart home. It makes controlling your temperature easier, lets you check up on your home through your phone, adds integration with voice commands, and could save you money by lowering energy bills. The best smart thermostats are the ones that offer easy installation and integration with your existing devices, and a software suite that's functional and useful. We researched and reviewed thermostats from Nest, Honeywell, Ecobee, and others to pick the best ones.
Works with many devices and Alexa voice commands
Saves of heating and cooling bills
Won't work with older apartments and homes
Compatible with Amazon’s Alexa voice-control service (Alexa sold separately), the Nest is the industry’s best-known name and, with its stainless-steel frame, it's one of the best designed smart products available today. Once you finalize the fairly simple installation process (30 minutes or less), the Nest immediately begins learning how you move around your house, adjusting temperatures automatically based on time of day through a series of sensors, your smartphone or hundreds of other smart home devices, including smart remote controls and connected cameras such as the Dropcam Pro.
It's also equipped with Wi-Fi, so controlling the Nest from your smartphone, tablet or laptop is a breeze and with the app you can easily track energy history. Extras such as home/away help exercise the cost savings by monitoring when nobody is home and automatically adjusting temperatures accordingly to save energy. Once you re-enter the home, Nest’s Farsight tech will light up the 2.08-inch (480 x 480) display presenting you with the time, temperature and outside weather. With anticipated cost savings between 10 to 12 percent on heating bills and 15 percent on cooling bills, Nest expects its devices to pay for themselves within the first two years of purchase with an estimate of $131 to $145 savings per year.
"The Nest offers the most intelligent and extensive control over your smart home. There are few devices that can learn your habits, routine, and activities better than it." — Ajay Kumar, Tech Editor
Works with Apple HomeKit and Amazon Alexa
Lacks motion sensors and advanced automation
While the cost savings are no joke, value buyers should look to Honeywell’s Lyric T5 for a smaller up-front cost with the same saving opportunities that other connected thermostats provide. Thanks to Honeywell’s exclusive uwp wallplate, installation is a breeze with C-wire configuration. The outdated-looking display belies its value-pricing, but you can easily pair the device with a range of connected devices, including Apple’s HomeKit and Amazon Alexa. The T5 features seven-day programming, which adjusts the temperature on-demand anywhere there’s a Wi-Fi or cellular connection and it also reminds you to change the air filter.
Once you switch on Apple HomeKit, you can control it with both Siri and geofencing, the latter of which utilizes mapping software to institute a radius around the house. Once in place, the geofencing allows the Lyric T5 to know whether you are home or away, which helps the thermostat adjust temperatures accordingly for additional cost and energy savings. Amazon Alexa fans will equally love the voice control letting you adjust the temperature without lifting a finger.
Sleek and attractive glass finish
Automatic temperature adjustment
Supports Bluetooth and Spotify
Works with other smart home systems
Ecobee has long been a leader in smart thermostats, and its latest proves its aim to surpass the standards it itself set. Sleek and attractive with a glass finish, the thermostat does more than just control how hot or cool your home is. Its Smart Sensor automatically adjusts the temperature depending on how many people are in one room at a time, and it even wields a quad-core processor. It also has built-in Bluetooth and Spotify compatibility, so it can play your favorite music.
The device gives you complete control, no matter where you are. While out, you can modify it or make changes using any Android or iOS device, and at home, you can use built-in Alexa to adjust the temperature, play music, and connect it to other smart home systems including those from Apple, Google, and Samsung.
"The Ecobee offers bells and whistles you won't find in any other smart thermostat on the market." — Alan Bradley, Tech Editor
Easy to install
Save energy cost
No color touchscreen
Missing some more advanced options
The Emerson Sensi features a dull, white frame that looks and feels very similar to your existing thermostat. Fortunately, it’s easy to install with the included C-wire (although you can also use two AA batteries to power if needed). Ultimately, the Sensi boils down to you telling it what you want out of temperature control and not the other way around ala systems like Nest or Ecobee that attempt to learn from your movement and behavior.
Gone are the color LCD screen, proximity sensor and location tracking inside your home. The focus here is solely on setting, changing and scheduling the temperature from anywhere in the world courtesy of the Android and iOS smartphone applications. A custom seven-day scheduling option helps reduce unnecessary energy expenses, as well as saving on HVAC energy costs. The lone splurge with the Sensi is the integrated Amazon Alexa support for voice control, but it feels more of an add-on than an absolute necessity.
Has many programmable options
On the older side
Can't learn routine
With good looks and a touchscreen display that’s easy to use, the Honeywell Wi-Fi smart thermostat is a good choice for voice control fans. Featuring support for Amazon’s Alexa service (Echo, Echo Dot sold separately), the model has a feature set that rivals more expensive options. Perks like a customizable touchscreen that can change colors to match your décor are good, but the free smartphone application for both Android and iOS helps you control temperature anywhere you have an Internet connection.
Choosing the programmable mode is the best way to save on annual heating and cooling costs. The one area where age impacts the Honeywell is the ability to learn your routine and adjust your temperature accordingly, but that’s hardly a deal breaker when the flip side is a best-in-class on-screen interface. With a setup process that asks questions about who is home during the day and preferred temperature when sleeping, the set-it-and-forget-it Honeywell is punching above its weight.
Supports mobile app
Control of custom zones and scheduling
Lowers energy costs
Lesser known brand
This Dimplex smart thermostat allows for control over every aspect of your heating. The mobile app lets you stay connected from anywhere, whether you’re adjusting your home temperature from the office or turning on the heat at a vacation property before you arrive. With its multi-zone capabilities, you can adjust conditions in four different zones within your house, customizing the temperature within certain rooms so all needs are cared for. A scheduling function ensures that your space is properly heated when you’re around — but energy (and costs) aren’t wasted when you’re not. Use the thermostat to program four different daily events, including wake, away, home, and sleep. The device includes an LCD touchscreen for easy temperature monitoring, and is pre-programmed to save on energy costs. The wireless technology, which claims to facilitate simple installation, allows it to connect and synchronize with Dimplex LPC, PCH, and RCH heaters around the house, offering you a single command point to control all of your heating and cooling systems.
Clean and simple design
Great multi-room support
Supports voice control
App could be better
The Honeywell Home T9 is a clean-looking Wi-Fi thermostat that puts everything you need in a simple package. It has everything you expect from a thermostat with sensors you can place in each room to adjust temperature and humidity, multi-room support, and an app that lets you do scheduling and geofencing with home and away modes.
Like other smart thermometers, the Honeywell Home T9 will learn the heating and cooling patterns in your house, and push alerts to you about temperature and filter changes. It supports both Amazon Alexa and Google Assistant, and has dual-band Wi-Fi connectivity.
Very simple setup
Doesn't require additional hub or even Wi-Fi
Missing some higher-end features
The Lux/Geo Smart Thermostat is a basic smart thermostat that has good compatibility with most symptoms and a very basic interface. It's not the best sleek design with its monochrome screen and control wheel, but it's simple to use and doesn't require any additional hub. You can even set it up without Wi-Fi.
In terms of functionality, the Lux/Geo covers most of the basics. It can do scheduling, has multiple power options for installation including battery and microUSB in addition to c-wire. It works with Amazon Alexa devices, provides system use reports, push alerts for temprature, and has an app to control Home/Away and support multiple zones and locations. Best of all, at under $100 it's one of the most affordable smart thermostats you can get.
Large, useful display
Lots of granular controls
Works with gas and power HVAC
Supports phones and tablets
The Bosch BCC100 Connected Control thermostat is a mouthful, but it backs up the big name with an equally big display. It has a large 5-inch full color display that gives you a visualization of everything you need to know about your home temperature. The touchscreen shows date, time, temperature control, humidity, fan operations, and modes. You can also access all this information from a smartphone or tablet.
Beyond the informational aspect, the BCC100 has all the features you'd expect from a smart thermostat. You can schedule temperature ranges, fan delays, and cycling for the entire week, it has Home/Away functionality, and there's a child lock to make sure your kids don't confuse the controls with a game. It'll work with HVAC systems that use gas and power, and is compatible with Alexa and Google Assistant devices.
If you have a home and existing smart devices, the Google Nest is the best smart thermostat to get. Aside from its brand reputation, it has a simple install process and is able to quickly learn your routine and movements on the house through its sensors. This lets it adjust temperatures on the go and connect with hundreds of other smart devices. For a more affordable option, the Honeywell Lyric T5 has much of the same features including the easy install, the HomeKit and Alexa integration, and programming and geofencing to save on energy.
While our expert reviewers and testers haven't yet reviewed any smart thermostats, when they do, they'll look at ease of installation, design, and software features. We install the smart thermostat in our home or apartments, evaluating how easy it is to connect and how compatible it is with our existing HVAC system. In addition, we look at key features like scheduling, automatic temperature adjustment, integration with HomeKit, Alexa, and other voice assistants. Finally, we look at the user experience as a whole, judging the value offered by the smart thermostat, and balancing it against the price and competition to make an ultimate judgement. All the smart thermostats we review will be purchased by Lifewire.
David Beren is a tech writer with more than 10 years of experience in the industry. He's covered telecom companies extensively and worked as a content marketing manager for major consumer brands.
Ajay Kumar is Tech Editor at Lifewire and has been working in the tech industry for over seven years. Previously published on PCMag, he's reviewed thousands of consumer electronics including laptops, tablets, phones, smart home devices, and voice assistants. He uses a variety of Amazon Alexa devices and an iSmartHome.
Alan Bradley is a Tech Editor at Lifewire. He's been working in the industry for over a decade. As former Senior Writer at Future, he's reviewed thousands of products, ranging from PC and smart home devices, to gaming hardware and accessories. He's also used just about every voice assistant there is.
Smartphone compatibility - Before buying your new smart thermostat, make sure that it supports your smartphone platform of choice, whether that is Android, Apple iOS, or something more obscure. You want to know that . you can actually control your new smart thermostat before getting one.
Virtual assistants - For those of you who have already stepped into the world of virtual assistants with the likes of Amazon Alexa and Google Home, confirm that the thermostat you select is also compatible. After all, instructing Alexa to change the temperature so that you don’t have to get out of bed is a rewarding experience.
Programmability - The thermostat may be smart, but you are still in charge. Check out each thermostat to see the programming options they provide. While some smart thermostats do most of the guesswork for you, others give you fine granular control over when the heating and cooling systems operate.