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A smart thermostat can be controlled remotely through a mobile app and can be connected to smart home devices like Google Assistant and Amazon Alexa. With a smart thermostat, you can create a schedule around when you want your home to be a certain temperature and regulate temperatures when you’re away from home.
To learn more about various features and our top recommendations, read our review on the best smart thermostats.
Top 5 Smart Thermostats
- Best Voice Control: ecobee SmartThermostat with Voice Control
- Best for Smart Homes: Emerson Sensi ST75 Touch Wi-Fi Smart Thermostat
- Simplest Design: Google Nest Learning Thermostat
- Budget Pick: Emerson Sensi ST55 Wi-Fi Smart Thermostat
- Easiest Installation: Honeywell Home T9 WIFI Smart Thermostat
Compare Top Smart Thermostats
| Product | Touchscreen | Warranty | Price |
|---|---|---|---|
| ecobee SmartThermostat with Voice Control | Yes | 3-year | $219.99 |
| Emerson Sensi ST75 Touch Wi-Fi Smart Thermostat | Yes | 3-year | $169.99 |
| Google Nest Learning Thermostat | Yes | 2-year | $249.99 |
| Emerson Sensi ST55 Wi-Fi Smart Thermostat | No | 3-year | $129.99 |
| Honeywell Home T9 WIFI Smart Thermostat | Yes | 1-year | $209.99 |
| Product | Touchscreen | Warranty | Price |
Best Voice Control: ecobee SmartThermostat with Voice Control
This smart thermostat from ecobee has a high price tag because of all of the smart features that come with it. You can control this thermostat in three ways—on the thermostat, through the mobile app, or with Alexa’s voice control.
Another unique element of this device is the addition of a sensor. This sensor will recognize if there are people at home or if the temperature is off and will adjust the temperature accordingly. Not to mention, this thermostat is compatible with Google Assistant, Apple Home Kit, Amazon Alexa, Samsung SmartThings, and IFTTT.
Key Features
- Includes a built-in Amazon Alexa and mobile app
- Has a SmartSensor that regulates the temperature of a room
- Comes with eco+, a free software upgrade to maximize energy efficiency
- Installation takes 45 minutes or less
- Comes with a three-year warranty
What Customers Are Saying
Some customers mentioned an easy installation, with some people hiring a professional installer and some customers installing the product on their own. Several reviewers were repeat ecobee customers who were upgrading their old ecobee with the newest generation. These repeat customers liked the addition of the sensor because it saved them from having to manually change the thermostat themselves.
However, there were some customer complaints about the thermostat not sticking to the desired temperature.
Best Smart Home Compatibility: Emerson Sensi ST75 Touch Wi-Fi Smart Thermostat
If you’re looking for a thermostat that can be easily integrated into your smart home, this may be the product for you. You can connect it to a variety of smart home platforms, including Amazon Alexa, Google Assistant, Apple HomeKit, and Samsung SmartThings, to make managing your devices easier.
On top of enjoying this product’s smart home integration, you’ll receive a bonus of electricity savings. With this thermostat, you can save up to 23% annually on your electricity bills.
Key Features
- Provides daily and historical energy usage reports
- Requires a C wire
- Compatible with Amazon Alexa, Google Assistant, Apple HomeKit, and Samsung SmartThings
- Installation includes built-in level, illuminated easy-click terminals, and step-by-step mobile app instructions
- Comes with a three-year warranty
What Customers Are Saying
What stood out about Emerson was the company’s customer service—while most customers said that installation was simple and could be completed by following the instructions in the owner’s manual and on the mobile app, customers who had trouble were able to contact a representative who would walk them through the rest of the process. Regarding complaints, some customers complained about the poor design of the app.
Simplest Design: Google Nest Learning Thermostat
Google Nest is a #1 Best Seller on Amazon, and its simple interface is one of the reasons why it’s such a popular product. The thermostat itself is a small circle that can be turned left or right to change the temperature in your home. For more complex functions, like Home/Away Assist, you can use the Nest mobile app. While other smart thermostats come in one or two colors, this one comes in more than five—you can choose from black, brass, copper, polished steel, stainless steel, or white.
Key Features
- Learns your schedule and preferred temperatures
- Has a mobile app
- Compatible with Amazon Alexa and Google Assistant
- The Home/Away Assist function automatically adjusts to an Eco Temperature when you leave your home to save energy
- Includes a two-year warranty
What Customers Are Saying
In terms of what customers liked about this smart thermostat, the simple design was a prime benefit. Customers also liked how the Nest thermostat came with all of the necessary materials for installation, including a screwdriver and optional backing plate. Common complaints from customers mentioned that the thermostat would disconnect from smart devices randomly and that it wouldn’t hold a charge. When these sorts of issues arose, customers struggled to get in touch with a customer service representative for assistance.
Budget Pick: Emerson Sensi ST55 Wi-Fi Smart Thermostat for Smart Homes
Emerson’s ST55 thermostat looks like your standard thermostat, with buttons on its side and bottom to control the temperature in your home. However, this product is considered a smart thermostat because of features like compatibility with other devices and control through a mobile app. Compared to the other smart thermostats in this review, the Emerson Sensi ST55 is the most affordable and comes with a three-year warranty.
Key Features
- Works with heating and air conditioning equipment in most homes (a C wire is required for heat-only, cool-only, and heat pump systems)
- Has a mobile app that allows you to remotely control the temperature from anywhere
- Installation takes 30 minutes or less
- Provides daily usage reports
- Comes with a three-year warranty
What Customers Are Saying
Customers can set up geofencing, scheduling, remote access, and other smart features that allow for complete control of their home’s temperature when they’re at home or away. This thermostat doesn’t require a C wire in most newer homes, which makes installation fast and easy. However, some customers complained that the thermostat would disconnect from the router and have trouble reconnecting.
Easiest Installation: Honeywell Home T9 WIFI Smart Thermostat
While most smart thermostats require connection to a C wire, the Honeywell Home T9 smart thermostat is easy to install and comes with an adapter that can be used in place of a C wire. Once the thermostat is installed, you have access to a variety of features, like temperature scheduling and alerts. For a wider range of features, you can purchase the model with a sensor to monitor the temperature of your home.
Key Features
- Learns your home’s heating and cooling patterns
- Regulates temperature in multiple rooms
- Delivers an efficient signal up to a 200-foot range
- Compatible with Google Assistant, Amazon Alexa, Samsung SmartThings, and Microsoft Cortana
- Comes with a one-year warranty
What Customers Are Saying
Customers found the setup process for the Honeywell Home t9 smart thermostat to be easy. Once the thermostat was connected and an account was created through the Honeywell app, the screens walked customers through the rest of the setup process. Most customers said that the on-screen instructions were sufficient and that they didn’t need to consult the owner’s manual.
Although Honeywell says you can connect the thermostat to a 5 GHz band, several customers reported that wasn’t the case and that it only worked when connected to a 2.4 GHz band.
Buying Guide to the Best Smart Thermostats
From HVAC compatibility to the installation process, here are a few important factors to consider before buying a smart thermostat for your home.
HVAC Compatibility
Not all smart thermostats will work with your heating and cooling system because of differing wiring requirements. Before you purchase a smart thermostat, visit the manufacturer’s website to check if it’s compatible with your type of HVAC system.
Electronics Compatibility
Part of the lure of a smart thermostat is that it works with the other electronics around your home, including your phone, laptop, Amazon Alexa, and Google Home Assistant. Before choosing a smart thermostat, decide what devices you want to control the thermostat from and determine if the product you’re considering connects with those devices.
Installation
Most smart thermostat manufacturers claim that their devices are easy to install if you read the owner’s manual and watch the instructional videos. However, smart thermostat installation may get tricky in the absence of a common wire, or C wire. A C wire allows for a continuous flow of 24 VAC power to your thermostat. Most smart thermostats require a connection to this wire, but older homes with older HVAC systems often lack it.
Some smart thermostat models, like Google Nest, can get by without a C wire by stealing power from other wires, but this can cause high-tech circuit boards to fail. If your HVAC system doesn’t have a C wire, you can either opt for a smart thermostat that doesn’t need this type of wire or consider hiring an electrician to install a C wire to make installation easier.
User Interface
Some smart thermostats will have touchscreen interfaces, while others will have more manual setups. We recommend reading customer reviews before purchasing one of these devices to determine what customers have said about how easy the interface is to use.
Frequently Asked Questions About Smart Thermostats
What makes a thermostat smart?
Though each smart thermostat will have different features, here’s a list of some of the common features included with one of these devices:
- Email alerts
- Integration with smart home devices
- Remote temperature control and scheduling
- Sensors to determine when someone is home
- Touchscreen
- Voice command
What are the benefits of a smart thermostat?
One of the biggest benefits of a smart thermostat is that you can save money on your electricity bill in the long term. A smart thermostat is more efficient than traditional HVAC systems because of features like the automatic ability to turn the temperature up or down when no one is home.
Another benefit of a smart thermostat is that you can remotely control the temperature when you’re away. With a standard thermostat, you can only manage the temperature in your home by manually adjusting the thermostat’s buttons.
How much do smart thermostats cost?
The average cost of a smart thermostat is between $100–$250. While this may seem like a lot, smart thermostats can typically pay for themselves in a few years by saving you money on monthly heating and cooling costs.
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