Smart thermostats are more than just a way to set the temperature in your home: they’re a streamlined tool to upgrade your home’s energy efficiency. A smart thermostat makes it easy to control your home’s climate via smartphone or voice control, all while helping reduce energy costs. Some can even learn your preferences, automatically adjust based on occupancy, and provide detailed energy usage reports.
However, if you’ve never bought a smart thermostat before or you don’t know how smart thermostats work, it can be difficult to sort through all the options. That’s why our team did the research for you, ranking the best smart thermostats on the market in 2025 to help you find the perfect one for your home. Read on to see our tips for choosing a smart thermostat, as well as which model may be best for your heating and cooling needs.
Top 4 Smart Thermostats at a Glance
- Google Google Nest Learning Thermostat (4th Gen): Best Overall
- Ecobee Premium Smart Thermostat + Air Quality Monitor: Best Voice Control
- Honeywell Home T9 WIFI Smart Thermostat: Best Multi-Room Solution
- Emerson Sensi Touch Smart Thermostat: Best Basic Option
Compare Top Smart Thermostats
| Product | Voice Control | Learning Capability | Room Sensors |
|---|---|---|---|
Google Google Nest Learning Thermostat (4th Gen)Check Price | Yes | Yes | Yes |
Ecobee Premium Smart Thermostat + Air Quality MonitorCheck Price | Built-in | Yes | Yes |
Honeywell Home T9 WIFI Smart ThermostatCheck Price | Yes | Yes | Sold separately |
Emerson Sensi Touch Smart ThermostatCheck Price | Yes | No | Sold separately |
Best Overall
Google Google Nest Learning Thermostat (4th Gen)
Simply put, the latest Google Nest Learning Thermostat is the pinnacle of smart climate control technology. This sleek device combines sophisticated learning capabilities to automatically program a schedule that’s custom-fit for you. It also comes with practical perks like the system health monitor to keep an eye out for HVAC issues. It may be pricey, but buyers can save in the long run with the Nest’s adaptive eco mode that helps cut down on energy costs.
Pros and Cons of Google Google Nest Learning Thermostat (4th Gen)
- Sophisticated auto-scheduling learns your preferences
- Premium design with high-resolution display
- Comprehensive smart home integration
- No C-wire needed for most HVAC systems
- Higher price point than competitors
- You may need to install a C wire if the thermostat has power issues or its battery drains
Key Features
- Adaptive learning technology automatically programs itself
- Nest Temperature Sensor compatibility for enhanced room control
- Adaptive Eco mode for maximum energy savings
- Works with both Alexa and Google Home
- The System Health Monitor can help discover issues with your HVAC system
- Compatible with most HVAC systems
- Includes a Nest Temperature Sensor (2nd gen)
What People Are Saying About The Google Google Nest Learning Thermostat (4th Gen)
Users consistently praise the Nest’s learning capabilities and the fact that it comes with a remote room sensor. Others mention how convenient it is that it doesn’t require a C-wire for most uses. Many buyers compliment the futuristic and sleek appearance, as well as its quick setup, thanks to its automatic system recognition.
However, some customers report problems with the Nest’s learning process, claiming that its internal tech was malfunctioning. Others are unsatisfied with the Google Home app’s functionality on certain devices. Still, most customers are extremely satisfied and reported energy savings after buying the Nest Smart Thermostat.
Best Voice Control
Ecobee Premium Smart Thermostat + Air Quality Monitor
The Ecobee Premium Smart Thermostat stands out from the crowd because it’s the only thermostat on our list with Siri and Alexa built-in for voice control abilities right out of the box. Much like other smart thermostats on the market, it learns your preferences so it can automatically lower the temperature when you’re sleeping or pre-heat/cool the home before you arrive. However, the Ecobee Premium bundle also includes a smart sensor and air quality monitor, offering extra benefits to your home efficiency.
Pros and Cons of Ecobee Premium Smart Thermostat + Air Quality Monitor
- Built-in voice control and included smart speaker
- Includes room sensor with premium package
- Includes a power extender kit for homes without a C-wire
- Some customers complain about inaccurate temperature readings
- The app isn’t as user-friendly as some competitors
Key Features
- Built-in voice control with multiple assistant options
- Included SmartSensor
- Comprehensive smart home compatibility
- Indoor air quality monitoring
- Support for additional room sensors
What People Are Saying About The Ecobee Premium Smart Thermostat + Air Quality Monitor
Users frequently highlight the convenience of built-in voice controls and the effectiveness of the room occupancy sensors. Many also compliment the easy setup process and the condition alerts for issues like high humidity and poor air quality.
However, other buyers are frustrated with the Ecobee app, saying that it’s filled with adds for Ecobee products and isn’t intuitive for users. Still, most customers are happy with their purchase, especially because of the built-in voice control and ease of use.
Best Multi-Room Solution
Honeywell Home T9 WIFI Smart Thermostat
The Honeywell Home T9 is great for managing temperatures across multiple rooms because of its multi-room display on the touchscreen and app.
If you connect smart room sensors in every room if your house, Honeywell’s geofencing capabilities can automatically adjust the temperature based on your phone’s location, making it ideal for larger homes or those with significant temperature variations between spaces. It also features learning capabilities like Smart Response and Adaptive Recovery, which work to learn how long it takes to heat or cool your home.
Pros and Cons of Honeywell Home T9 WIFI Smart Thermostat
- Excellent multi-room display and temperature management
- User-friendly touchscreen interface
- Works with all major smart home technologies
- Reasonable price
- Requires batteries for power
- Room sensors sold separately
Key Features
- Smart room sensor compatibility
- Multi-room display
- Intelligent learning capabilities
- Geofencing capability
- Mobile device control
- Filter and temperature alerts
What People Are Saying About The Honeywell Home T9 WIFI Smart Thermostat
Users appreciate the T9’s ability to maintain consistent temperatures across multiple rooms with smart sensors. However, some mention the additional cost of room sensors as a drawback. Customers also praise the geofencing feature for its reliability, but some buyers have conflicting claims of the simplicity of its setup process. Overall, most users are satisfied with their purchase and happy with how simple it is to use.
Best Basic Option
Emerson Sensi Touch Smart Thermostat
This simple smart thermostat offers essential features in a straightforward package, making it an excellent choice for those seeking basic smart functionality without complexity. It also costs less than half of the top brands on the market, so it’s a great value for the money.
However, the affordable price point doesn’t necessarily equal affordable features. This thermostat still comes with practical perks like mobile app integration, voice control compatibility, usage reports, maintenance reminders, and alerts about your HVAC system.
Pros and Cons of Emerson Sensi Touch Smart Thermostat
- Easy installation and setup
- Large color display
- Affordable price point
- Limited advanced features
- Basic mobile app functionality
- Requires C-Wire for installation
Key Features
- Simple installation process
- Battery-powered operation
- Precise temperature control
- Mobile app integration
- Voice control compatibility
What People Are Saying About The Emerson Sensi Touch Smart Thermostat
Users appreciate the straightforward installation and reliable basic functionality. Many buyers view the no-frills design as positive, though some users note the limited advanced features compared to premium models.
Numerous customers praise the easy setup, claiming the thermostat’s mobile app walks you through the installation. Others say that it’s easy to read the temperature on the Sensi display from across the room or on your smartphone. Some buyers are disappointed in the company’s customer service but are still pleased with the product as a whole.
What to Know Before Buying a Smart Thermostat
HVAC Compatibility
Before purchasing a smart thermostat, verify that it’s compatible with your current HVAC system. Most modern systems work well with smart thermostats, but older systems may require additional wiring or adapters. Check the manufacturer’s compatibility tool with your specific HVAC setup.
Smart Home Integration
Consider which smart home ecosystem you use (Google Home, Amazon Alexa, Apple HomeKit) when purchasing a smart thermostat to make sure it’s compatible with your existing setup. Some thermostats work better with certain platforms than others.
Installation Requirements
Many smart thermostats require a C-wire for power. While some include power adapters or alternative solutions, you should check your home’s wiring setup before purchase. We recommend professional installation for homes without existing C-wire connections.
Energy Monitoring and Reporting
For the best insight into your heating and cooling costs, look for thermostats that provide detailed energy usage reports. These reports can help maximize energy savings and show you where you can improve your efficiency.
Additional Features to Consider
If you want a smart thermostat that goes above and beyond the norm, look for the following features when you’re shopping:
- Energy-saving programs
- Room sensors for temperature balancing
- Humidity monitoring and control
- Air quality monitoring
- Weather forecasting
- Maintenance reminders
Smart Thermostat FAQs
How much can I save with a smart thermostat?
According to Google Nest’s research, you can expect to save roughly 10–15% on heating and cooling costs with a Nest smart thermostat. Your actual savings depend on factors like usage patterns, climate, and home insulation.
Do I need professional installation?
While many smart thermostats are designed for DIY installation, we highly recommend professional installation if you’re inexperienced with HVAC wiring. Read our guide on upgrade a thermostat without changing wiring for more information.
Can smart thermostats work without WiFi?
Most smart thermostats will continue to operate as basic thermostats without WiFi, but advanced features and remote control access require internet connectivity.
How long do smart thermostats last?
Quality smart thermostats typically last around 10 years, but they can sometimes last longer with proper maintenance. If your thermostat is malfunctioning or older than 10 years old, we recommend getting a newer model.
Our Methodology
This Old House has empowered homeowners and DIY-ers for more than four decades with top-notch home improvement advice in the form of television programs, print media, and digital content. Our team focuses on creating in-depth product and service review content. To date, we’ve published over 1,600 reviews on products in the home space, including power tools, outdoor equipment, major appliances, kitchen gadgets, electronics, and more that focus on product quality and helpfulness to our readers.
To provide our readers with the best recommendations possible, we rely on several key sources of information to help guide our selection process.
Initial Research: Our research process began by generating a list of garbage disposals with a significant number of verified buyer reviews and an average customer review rating of 4–5 stars. We looked at positive and negative reviews alike, focusing on information from both satisfied and critical buyers.
Expert Insights: To complement our in-house expertise, our team looked at reviews and videos from trusted publications and independent testers, spoke with subject matter experts, and drew insights from reader contributions.
Final Product Selection: We then began fine-tuning our list by replacing older models with the latest versions and eliminating any discontinued models. From there, we compared each model’s feature set to create a final shortlist, selecting the best-in-class options for various buyers, budgets, and scenarios.
Once we conclude our research, we craft a comprehensive, user-friendly article of recommended products and additional information to help our readers make the right purchase.