The 8 Best Smart Thermostats of 2021

Control your thermostat on-the-go

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Heating and cooling your home accounts for a significant part of your energy bill. In fact, according to data from U.S. Environmental Protection Agency, heating makes up 29 percent of the annual energy bill, and cooling accounts for 13 percent. The EPA also notes that adjusting your thermostat accordingly when you’re sleeping or away from home could save you $180 a year. 

A smart thermostat is one way to control your usage and lower your utility bill. A smart thermostat is also easy to use and tends to look much more stylish on your wall than most regular thermostats.

Whether you’re looking for functionality, style, or both, these are the best smart thermostats.

Our Top Picks
The SmartSensor allows you to place it in the room you are in, and it will balance the temperature to keep you comfortable.
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Energy Star certified, this thermostat is designed to decrease your energy consumption and can be controlled remotely.
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Best for Smaller Homes:
Ecobee3 Lite Smart Thermostat at Amazon
It can be controlled by using an app and is compatible with several smart home systems and the Smart Sensor.
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This can keep the temperature comfortable in multiple rooms and automatically adjusts the temperature when the house is empty.
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Available in a variety of colors, this thermostat is easy to install and has a high-resolution display.
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Best for Apple HomeKit:
Honeywell Home T5 at Amazon
This Energy Star rated thermostat is compatible with Alexa, Google Assistant, and the Apple HomeKit using Siri.
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The large, clear display is easy to read, and the simple, well-defined fingertip controls make it easy to use.
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Best with Baseboard Heaters:
Mysa Smart Thermostat at Amazon
Quick to install, this thermostat can be used with 120 to 240V baseboards and allows you to monitor your heat remotely.
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Best Overall: Ecobee Smart Thermostat with Voice Control

ecobee SmartThermostat with Voice Control
What We Like
  • Compatible with SmartSensor

  • Energy Star certified

  • Built-in Alexa

  • Compatible with Smart home systems

What We Don't Like
  • Expensive

Dimensions:  4.29 x 4.29 x 1 inches | Weight: 1.77 ounces | Self-Installation:  Yes | Works Offline: Yes

If you want the top-of-the-line smart thermostat, the Ecobee Smart Thermostat with Voice Control has everything—and does everything. It includes a SmartSensor that you can place in the room that you’re in, and it will balance the temperature to keep that room comfortable. You can also adjust the temperature remotely using the Ecobee App. The thermostat is also ENERGY STAR certified, and the beautiful glass display looks good on any wall. Alexa is built-in, making it easy to connect to a smart speaker to listen to music, make phone calls, or activate other Alexa devices by simply speaking. The thermostat also works with Google Assistant, Apple HomeKit, and other smart home systems. 

Best Budget: Google Nest Thermostat

Google Nest Thermostat
What We Like
  • Energy Star certified

  • Can be controlled remotely

  • Monitors HVAC System

  • Programmable thermostat

What We Don't Like
  • No lock setting

Dimensions:  3.31 x 3.31 x 1.07 inches | Weight: 5 ounces | Self-Installation:  Yes | Works Offline: Yes

If you’re looking for an economical option that still works well, consider the Google Nest Thermostat. It’s also ENERGY STAR certified, so it is designed to decrease your energy consumption. The thermostat has a programmable thermostat, so you can choose specific times for it to come on or go off. However, it can be controlled remotely via your smartphone, tablet, or laptop. In addition, it senses when the home is empty and will adjust the home’s temperature accordingly. The Google Nest Thermostat also monitors the HVAC system and notifies you when there is a problem with the system.

Best for Smaller Homes: Ecobee3 Lite Smart Thermostat

ecobee Lite SmartThermostat
What We Like
  • Energy Star certified

  • Budget-friendly

  • Compatible with SmartSensor

  • Compatible with Smart home systems

What We Don't Like
  • No voice control or built-in streaming

  • Does not include a SmartSensor

Dimensions: 4.05 x 1 x 4.05 inches | Weight:  1 pound | Self-Installation: Yes | Works Offline: Yes

If you live in an apartment or a smaller house, you may not need all of the features on the Ecobee SmartThermostat with Voice Control. The Ecobee3 Lite is a more economical option that’s still ENERGY STAR certified to help you save on annual energy costs. It doesn’t have voice control, hands-free calling, Alexa Built-in or Spotify and Bluetooth streaming, and it does not include a SmartSensor. However, the thermostat is compatible with Smart Sensor, and it can be controlled with the Ecobee App. In addition, the thermostat is compatible with Alexa, Google Assistant, Apple HomeKit, and several other smart home systems.

Best for Multiple Zones: Honeywell Home T9 Smart Thermostat with Sensor

Honeywell Home T9 WIFI Smart Thermostat, Smart Room Sensor Ready.jpg
What We Like
  • Smart room sensor

  • Location-based geofencing

  • Compatible with voice assistants

What We Don't Like
  • Light is very bright; not dimmable

Dimensions:  3.7 x 4.92 x 0.94 inches | Weight:  1.31 pounds | Self-Installation: Yes | Works Offline: Yes

The Honeywell Home T9 Smart Thermostat with Sensor is good for controlling the temperature in multiple rooms. Each smart room sensor ensures that the temperature is right in that room—and that’s important because when you’re in the bedroom, you don’t want the temperature to be based on your empty living room. If there are multiple people in your home, you can get multiple smart room sensors to ensure that everyone’s room has a comfortable temperature. The thermostat also uses location-based geofencing to determine when the house is empty and then adjust the temperature accordingly. The thermostat works with the Honeywell App, as well as Alexa, Google Assistant, Cortana, and other voice assistants.

Best Design: Google Nest Learning Thermostat 3rd gen

 Google Nest Learning Thermostat
What We Like
  • Available in multiple colors

  • Creates a schedule based on patterns

  • Monitors temperature in multiple zones

  • Easy to install

What We Don't Like
  • No lock setting

Dimensions: 6.5 x 6.5 x 3 inches | Weight:  8.6 ounces | Self-Installation: Yes | Works Offline: Yes

What’s not to like about the Nest Learning Thermostat 3rd generation? It is available in a variety of colors, including black, brass, copper, white, and mirror black, so you’re sure to find one that fits your décor style. The thermostat learns your patterns and uses this information to create a schedule, and also uses geofencing to sense when the home is empty and adjusts the temperature accordingly. In addition, it monitors the temperature in multiple zones. The thermostat is compatible with most HVAC systems and easy to install. In addition, the high-resolution display makes it easy to see the temperature from across the room. The Nest Learning Thermostat 3rd Generation Thermostat works with Alexa and Google Assistant.

Best for Apple HomeKit: Honeywell Home T5

Honeywell Home RCHT8610WF2006
What We Like
  • Energy Star certified

  • Compatible with voice assistants and Apple HomeKit

  • Suspends usual settings when on vacation

What We Don't Like
  • No remote sensors

Dimensions: 4 x 4 x 1.25 inches | Weight: 1.76 ounces | Self-Installation:  Yes | Works Offline: Yes

It’s more economically priced than the Honeywell Home T9, but the ENERGY STAR-rated Honeywell Home T5 still has a lot of features. It’s easy to install, works with your smartphone or other mobile devices via the Honeywell Home App, and is also compatible with Alexa, Google Assistant, and Apple HomeKit using Siri. The thermostat also detects when no one is home and adjusts the temperature. Plus, it has 7-day flexible scheduling or location-based temperature control, so when you’re off on vacation, it can suspend your usual settings.

Best with Large Clear Text: Orbit 83521 Clear Comfort Programmable Thermostat

Orbit 83521 Clear Comfort Programmable Thermostat
What We Like
  • Easy to read display

  • Well-defined fingertip controls

  • Easy to install

  • Affordable

What We Don't Like
  • Not as thin as other devices

Dimensions:  1.3 x 5.3 x 3.25 inches | Weight:  9.3 ounces | Self-Installation: Yes | Works Offline: Yes

If your eyesight’s not as good as it used to be, the large display on the Orbit 83521 Clear Comfort Programmable Thermostat is easy to see. The black text is large and well-contrasted against the backlit LCD screen. It’s also easy to use, with simple, well-defined fingertip controls. The thermostat integrates smart system logic designed to ensure that temperatures don’t over-fluctuate. This helps to keep the readings accurate and consistent. The thermostat is easy to install, and it can be programmed for up to 7 days.

Best with Baseboard Heaters: Mysa Smart Thermostat

Mysa Smart Thermostat for Electric Baseboard Heaters
What We Like
  • Install quickly

  • Location-based geofencing

  • Compatible with voice assistants and Apple HomeKit

What We Don't Like
  • Not compatible with 12 to 24V systems

Dimensions:  1.3 x 5.3 x 3.25 inches | Weight:  9.3 ounces | Self-Installation: Yes | Works Offline: Yes

If you don’t have an HVAC system, you can still enjoy the convenience and benefits of a smart thermostat. The Mysa Smart Thermostat for Electric Baseboard Heaters can be used with 120 to 240V baseboards and electric fan-forced heaters. It installs quickly and allows you to monitor your heat remotely on your smartphone or tablet. The thermostat can be scheduled for specific temperatures at certain times, and it also uses geofencing to know when no one is home. The Mysa Smart Thermostat can also be used with Alexa, Google Assistant, and Apple HomeKit.

Final Verdict

The best overall smart thermostat is the Ecobee Smart Thermostat with Voice Control (view at Amazon). It includes a smart sensor (and the option to purchase additional sensors), built-in Alexa, and the Ecobee App makes it easy to control the temperature remotely. Our second choice is the Google Nest Thermostat (view at Amazon), which is economically priced and can also be controlled remotely.

What to Look for in a Smart Thermostat

Compatibility

If you have smart home platforms and home assistants, like Apple HomeKit, Alexa, Google Assistant, you may want a smart thermostat that can integrate seamlessly. This makes controlling the thermostat even easier. Some thermostats also work with other smart devices, including cameras and lights. 

Features

Usually, the more features a smart thermostat has, the more expensive it will be. The ability to control your smart thermostat remotely is one feature that many people are willing to pay for. Fortunately, it’s included at practically every price point. Also, geofencing allows your thermostat to access your phone’s location feature to determine when you’ve left the house—or when you’re approaching. If you live in a large home, something else to consider is remote sensors, which can help you ensure that the most important rooms maintain the desired temperature. 


Ease of Installation

The smart thermostats on this list are easy to install (that was one of the features we weighed). However, some thermostats, like the Mysa Smart Thermostat for Baseboards, will require one neutral or second live wire for installation. Always be sure to turn off the power of the thermostat before undertaking any installation project. Also, if you don’t feel comfortable working with electrical equipment, don’t hesitate to contact an electrician to install the smart thermostat for you.  

Why Trust The Spruce?

Terri Williams is a professional writer who has tested hundreds of products. She has product review bylines at Tom’s Guide, and both home improvement advice and product review bylines at Realtor.com, Bob Vila, Apartment Therapy, and Heavy.com.

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