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Never Again Be Too Hot or Too Cold with the Best Smart Thermostat for Your Space

Tired of being either too hot or too cold? It’s maybe time to take a look at replacing your thermostat. Not only will choosing an updated thermostat allow you to feel more comfortable in your home, but it will also probably save you a bundle in decreased energy costs. In this article, we’ll discuss what a thermostat is, the differences between thermostat types, and compare different smart thermostats. By the end of this article, we hope you’ll have a handle on how to go about determining which thermostat is the best one for you.

Thermostat Definition

Before we look too closely at the specifics of a thermostat, it might be helpful to identify what, exactly, a thermostat is…and what it isn’t. A thermostat is a device that either regulates temperature automatically by itself or that activates a temperature-regulating device based upon temperature readings. Essentially, it is the thermostat that will (hopefully) automatically control heating or cooling in a space so as to maintain a specified temperature range. A thermometer within the thermostat triggers electrical switches, which in turn either activates or deactivates a piece of heating and/or cooling equipment.

Smart Thermostats: Providing Real Comfort and Real Cost Savings

An effective thermostat is one that helps you save money on the cost of heating and cooling your home. The best thermostat will do this on its own, based on parameters you want and set, without any further thought on your part. Or, at least, very little follow-up thought. So, in actuality, the best type of thermostat regulates your comfort level and, to some degree, even your budget, as it’s smartly regulating your heating and cooling.

Old thermostats have limited ability to regulate your home’s temperature well or accurately, let alone smartly. Even the most basic modern thermostats do a better job of controlling temperature in your home, which ultimately results in improved comfort for you as well as your wallet. What’s more, energy-saving thermostats can cut your energy bills by up to 20%, which means that the cost of a new thermostat will quickly pay for itself…and then some.

Now, consider taking your comfort level up even one more notch as you think about what a smart thermostat has to offer, even above and beyond a more modern energy-efficient one. Smart thermostats will cost more from the get-go, but they pay you back with convenience and useful features (voice-control the heat or A/C, anyone?) as well as provide very real energy cost decreases.

Thermostats Through The Years

The following is a summary of the five primary types of thermostats in homes today – what they are, and what they offer:

  • Mechanical Thermostats – These are the earliest versions of thermostats and are the least technologically advanced and, therefore, the least expensive. They use a bimetallic strip to gauge the temperature and, based upon those readings, will adjust the heating or cooling accordingly. These are commonly found in older homes and apartments.
  • Non-Programmable Thermostats – These thermostats are relatively inexpensive in and of themselves. They need a human to adjust the temperature settings manually, though some non-programmable thermostats are digital thermostats with digital operation. Unfortunately, this type of thermostat is not helpful in cutting energy costs, unless someone is standing guard and making adjustments throughout the night and the day.
  • Programmable Thermostats – This type of thermostat requires you to preset, or program, your heating and cooling preferences. The thermostat then automatically adjusts the temperature based upon those preferences. This programmability saves you in a variety of areas and ways: (1) time, because once you’ve programmed the thermostat, you no longer need to worry about it, (2) convenience, and (3) money, as the automatic adjustment keeps you from heating or cooling your home when you don’t need to or to a degree that you neither need nor want.
  • Wireless Thermostats – These thermostats begin to increase in cost, because their technological capacity and requirements are a bit more complex than the previous thermostats. Wireless thermostats allow you to adjust your home’s temperature remotely, which is particularly useful and beneficial when you’re away from home or if you have pets or other individuals in your home who might have specific temperature needs (e.g., infants, handicapped or disabled individuals, or the elderly). Wireless thermostats allow you significant freedom in your home’s temperature controllability and, along with that, the opportunity to really decrease energy costs.
  • Smart Thermostats – This type of thermostat is relatively new in the world of thermostats and, with their increased technological capacity, come with a higher price tag upfront. It is readily argued, however, that those upfront costs are quickly offset with energy savings due to the smart functionality. Essentially, a smart thermostat will learn what your household’s temperature preferences are throughout the day and night and then adjust temperatures accordingly. There is a variety of what a smart thermostat will and will not do for you, based upon the model you choose, but some even use motion sensing technology to determine whether or not someone is in a room and adjust the temperature based upon that. Smart thermostats typically have remote access via an app on your smart phone and voice control as well.
Carrier Cor 7 Day Programmable Wi Fi Thermostat with Energy

How To Choose The Best Thermostat For You

Although smart thermostats are appealing to many for a variety of reasons, they may or may not be the best choice for you and your space. So how do you go about choosing which thermostat to buy? Here’s a basic outline of the considerations and steps you should take:

Identify existing HVAC system.

Before you make any steps toward choosing a good thermostat, you need to know which thermostats would even be compatiblewith your existing heating, ventilation, and air conditioning (HVAC) system. You’ll need to know if your HVAC system fits into any of the following categories:

  • 1 Stage – This is a system that has the heating and air conditioning units separated.
  • 2 Stage – Also called a Multi-Stage Heat or Cool, this is a system that has heating or cooling units that have both high and low speeds.
  • Direct Line Voltage – This means that your heating and/or cooling system operates on either a 110 or 240 direct current power source; this is more prevalent in older homes to provide power to the thermostat.
  • Zoned Heating & Cooling – Also referred to as Zoned HVAC, this is a single HVAC system that is controlled by individual thermostats in different areas.

Determine what equipment the thermostat needs to control.

While on the surface this may seem rather straightforward (doesn’t the thermostat just control the heater and air conditioning?), it may or may not be so simple. For example, some thermostats are designed for furnace-only control, while others will work most effectively controlling both the furnace and an air conditioner, a heat pump, or other equipment. Don’t worry – the thermostat manufacturer will clearly identify compatible HVAC systems.

Identify if you need Line-Voltage or Low-Voltage.

These are the two primary thermostat types, and their differentiation is important. Line-voltage thermostats are designed specifically for single heating systems. These include such heating systems as baseboard heaters and radiator valves. Low-voltage thermostats are generally used in central heating and cooling systems that use gas, oil, or electricity. These are typically more efficient and accurate thermostats, often with programmable options.

Check C-wire compatibility.

The C-wire, or common wire, is an extra wire that provides power to enable extra smart thermostat features, such as a touchscreen. The thermostat you’re interested in may or may not require a C-wire, and your existing system may or may not have it. If you’re unsure about either of these, you’ll probably want to consider seeking a professional’s house call, to check out both your current system as well as the new thermostat you want to install.

Smart Thermostat Product Descriptions & Comparisons

Below is a summary of several popular smart thermostats on the market today. Each thermostat is described in detail, along with a bulleted pros and cons list and any awards that particular thermostat may have received.

1. ecobee4 Alexa-Enabled Thermostat with Sensor

ecobee4 Alexa-Enabled Thermostat with Sensor

The ecobee4 is not just a smart thermostat (a task it performs well in its own right), but it’s also a smart speaker. It’s considered by many to be the latest and greatest in the smart thermostat realm, due in large part to its built-in Alexa voice service (you don’t even need an Amazon Echo or Echo Dot!) and far-field voice technology. Ecobee4 also utilizes accessory support for humidifiers, dehumidifiers, ventilators, heat recover ventilation, and energy recovery ventilation.

Of course, as a true smart thermostat, ecobee4 can be controlled remotely via the app on your smart phone. It is also compatible with other home automation systems, such as Apple HomeKit, Samsung SmartThings, IFTTT, and hundreds of others. The installation and setup is designed intuitively, requiring most people just a few minutes to get their ecobee4 system operating. Additionally, ecobee4 is designed aesthetically, with a modern touchscreen base display that’s sleek as well as easy to use.

The methodology of ecobee4 is somewhat unique, in that it utilizes a primary thermostat base in conjunction with other sensors placed throughout your home (purchased in sets of two after the ecobee4 starter kit’s single sensor). This division of smart sensing allows ecobee4 to heat/cool the rooms that matter the most, which are the rooms that are occupied. This improves not only your comfort level, but also your energy bills because you’re not heating or cooling unnecessary spaces. Because of this, ecobee4 can save an average of 23% per year on heating and cooling costs (Business Insider).


  • Unique sensor system, with separate sensors from the main base for more accurate temperature control in different rooms or zones.
  • Remote access.
  • Open application programming interface (API), allowing ecobee4 to integrate and interact with other smart home softwares, which in turn provides a nice variety of control options.
  • Hardwired, which means it doesn’t rely on battery life, which means it is more reliable.
  • Cuts down on energy costs, due to its optimal sensor-based smart temperature control.
  • Aesthetic touchscreen design for a sleek, modern look.


  • Additional sensors add to the cost of the smart thermostat system.
  • Some glitches and quirks experienced with Alexa integration, based on reviews by Business Insider.


  • Thermostat with Best Integration: Lifewire
  • 4.5 out of 5-star rating on CNET.

2. ecobee3 lite Smart Thermostat

ecobee3 lite Smart Thermostat 

The ecobee3 is an excellent less-expensive smart thermostat. While it doesn’t come with the remote sensors or occupancy sensors of the ecobee3, although those can be purchased separately and integrated easily to facilitate highly accurate temperature readings and modifications, whether heating or cooling the home. The smart thermostat is compatible with Apple HomeKit, Samsung SmartThings, and Amazon Alexa, making it a convenient choice particularly in a home that is trending toward smart home automation. Not only does it work well, but the ecobee3 lite also looks well in its aesthetically pleasing, sleek design.

You can add up to 32 separate sensors to the ecobee3 lite, which sense not only temperature but also humidity changes and, consequently, are able to immediately adjust and adapt the heating and cooling mechanisms to create a more comfortable room. These sensors can also help to monitor whether or not a room, or the home in general, is occupied or not and make energy usage adjustments accordingly. In and of itself, the ecobee3 lite has programming and scheduling features, although it requires a manual switch back to its schedule if you use voice or app control to change it away from the pre-programmed temperature.


  • A great budget option for smart thermostats.
  • Attractive physical design with aesthetically pleasing touchscreen.
  • Programmable with a temperature schedule.
  • Expandability, with the smart thermostat able to accommodate up to 32 separate sensors. Multiple sensors on a single thermostat system allow for improved energy adjustability.
  • Remote controllability from a smart phone, tablet, laptop, or other smart device (iOS or android) from anywhere across the globe.
  • Compatible with other smart home systems, including Apple HomeKit, Samsung SmartThings, and Amazon Alexa (for voice control).
  • Software updated automatically so ecobee3 is always up-to-date, smarter, and better connected.
  • Decreased energy costs can reach 23% savings each year (compared to a stable 72 degrees F).


  • Additional sensors add to the cost of the smart thermostat system.


  • Best Programmable Thermostat: Lifewire
  • Smart Thermostat Budget Pick: The Wire Cutter
Get it from Amazon: ecobee3 lite Smart Thermostat.

3. Nest Learning Thermostat, 3rd Generation

Nest Learning Thermostat, 3rd Generation

The 3rd Generation Nest Learning Thermostat is fairly easy to install without professional help, usually taking around a half an hour. You don’t need to program this smart thermostat, as it immediately begins using an Auto-Schedule feature to learn your schedule and temperature preferences over time. The Nest works well as an isolated unit, and it also works well when it’s integrated with other smart home components.

Integrated sensors include not just temperature, but also humidity, near-field activity, far-field activity, and ambient light. The Nest Learning Thermostat also knows the location of your phone and is able to adjust the temperature when you’re not at home (although you can easily adjust the temperature manually in your app if desired).

A Farsight feature in the Nest Learning Thermostat senses your approach from across the room and automatically lights up the 2.08” display to show you time, temperature, and outside weather. This smart thermostat is equipped with wi-fi, which allows for remote access and control via your smart phone, tablet, laptop, or other smart device with the Nest app. You can also track energy history, which is both interesting and informative in determining your future energy needs.


  • Easy to use.
  • Intuitive; does not require pre-programming because the thermostat smartly learns your schedule and temperature preferences over time instead.
  • Efficient – the first thermostat to be ENERGY STAR certified.
  • Various built-in smart sensors for temperature, humidity, near-field activity, far-field activity, and ambient light.
  • Saves you money – saves users an average of 10%-12% on heating bills and 15% on cooling bills, which pays for itself within two years, with an estimate of $131-$145 savings per year.
  • Aesthetic design, with a slim, sleek stainless steel surround and a large, clear display that lights up when it senses your approach from across the room.
  • Compatible with smart home systems such as Google Home and Amazon Alexa, allowing hands-free voice control.
  • Simple and inexpensive to install.


  • Some users experienced issues with the software/app.
  • A small percentage of the Nest Learning Thermostats tested were found to be lemons.


  • Best Thermostat Overall: Business Insider’s pick for the best thermostat you can buy, based on their research.
  • Best Overall Thermostat: Lifewire.
  • Best Smart Thermostat: The Wire Cutter
  • 4.5 out of 5-star ratings on PCMag, CNET, and Digital Trends.

4. Sensi Smart Thermostat

Sensi Smart Thermostat, Wi-Fi, UP500W, Works with Amazon Alexa

After you connect your Sensi Smart Thermostat to your home wi-fi network, you will be able to conveniently control it from anywhere via your downloaded Sensi app. The app first helps with easy installation, with step-by-step instructions. Sensi Smart Thermostat is extremely accurate (within plus or minus 1 degree) and uses location-based geofencing technology to determine when you’re not home and subsequently decrease energy usage during those times. Or, you can use the seven-day flexible scheduling option to create your own preferred heating and cooling schedule. All settings can be easily modified through the app.

Other features that are appealing in the Sensi Smart Thermostat include the ability to link multiple thermostats onto one account, and an indoor humidity sensor. You can also use voice control to heat or cool your home through other smart home systems (e.g., Amazon Echo, Wink).


  • Easy installation, with a convenient app to guide you in installation.
  • Remote access (control, scheduling) of your home’s temperature settings via wi-fi connectivity.
  • Geofencing capabilities to automatically cut down on energy usage when you’re not at home.
  • Gives highly accurate temperature settings, within plus or minus 1 degree.
  • A variety of temperature control options and settings.
  • Indoor humidity sensor.
  • Option to control multiple Sensi Smart Thermostats from one single account.
  • Compatible with Amazon Echo and Wink smart home.


  • Requires reliable, consistent wi-fi connection to work well.
  • Incompatible with some small home products and setups.


  • J.D. Power award: “Highest in Customer Satisfaction with Smart Thermostat,” 2016 (the only smart thermostat brand to receive a J.D. Power award).
Get it from Amazon: Sensi Smart Thermostat.

5. Honeywell Lyric T5 Wi-Fi Smart 7-Day Programmable Touchscreen Thermostat

Honeywell RCHT8610WF2006 Lyric T5 Wi-Fi Smart 7 Day Programmable Touchscreen Thermostat

This smart thermostat costs significantly less than others on the market, so value seekers should take a serious look at the Honeywell Lyric T5. The upfront costs are smaller, but the same money-saving features exist with other connected thermostats. A Honeywell-exclusive wallplate provides for easy installation with C-wire. Once installed, you can input a seven-day program, although you can change the temperature on-demand anytime and anywhere there’s a wi-fi or cell connection.

The Lyric T5 integrates easily with other smart home systems and devices, including Apple HomeKit and Amazon Alexa. You can control the Lyric T5 with your voice, and it also does geofencing, which utilizes mapping software and technology to sort of create a bubble/radius around your house. Once the smart thermostat senses that you’re away from home, it will adjust temperatures accordingly to further help you save on energy costs.


  • Simple installation via the Honeywell uwp wallplate.
  • Can easily be paired with other connected smart devices, such as Apple HomeKit and Amazon Alexa.
  • Seven-day programming available.
  • Geofencing technology, allowing the thermostat to sense when you are away from home and further reduce energy costs by adjusting the temperature accordingly.
  • Remote controllability via wi-fi or cellular connection.
  • Air filter change reminders.


  • Aesthetics lean toward a more outdated look than other smart thermostats.


  • Best Value Thermostat: Lifewire

6. Honeywell RTH958OWF Smart Wi-Fi 7-Day Programmable Color Touch Thermostat

Honeywell RTH958OWF Smart Wi-Fi 7-Day Programmable Color Touch Thermostat

This smart thermostat is a favorite of people who live and die by voice-controlled smart devices, because it is, indeed, compatible with Amazon Alexa. Not only does the smart thermostat look well, with its simple, contemporary lines and easy-to-use color touchscreen, but it also provides users with plenty of features that make them happy…and at a lower price point than many competitors.

The touchscreen is customizable, including changing colors to match your home’s décor. There is also a free app for your smart device (either android or iOS) that allows you to control temperature remotely with wi-fi connectivity. When you set up the Honeywell smart wi-fi thermostat, you will be asked questions about who is home during the day, and what is your preferred temperature while you’re sleeping. Thus, you can program in your regular life, then move on to other things and let the smart thermostat do its thing.


  • One of the first smart thermostats on the market.
  • Aesthetic rectangular design with attractive color-changing touchscreen display that is customizable.
  • Best-in-class on-screen interface.
  • Provides features comparable to more expensive smart thermostat options, but at a lower price.
  • Wi-fi connectivity allows for remote control of temperature.
  • Controllable via iOS or android smart phone app.
  • Programmable mode option to allow you to improve energy efficiency, based upon your regular schedule and answers to on-screen questions about lifestyle and preferences.
  • Voice controllability via Amazon Alexa.


  • Does not learn your schedule and temperature preferences; these must be preset and programmed into the smart thermostat.


  • Best Voice Control: Lifewire

7. Emerson Sensi Wi-Fi Thermostat

Honeywell RTH958OWF Smart Wi-Fi 7-Day Programmable Color Touch Thermostat

This is a very basic smart thermostat; if you prefer something that looks and feels sort of like your old thermostat (but with improved capability and functionality), you might look a little more closely at the Emerson Sensi. You can use the included C-wire to install this thermostat easily, or you can alternatively choose to use two AA batteries to power it. In a nutshell, this thermostat will do what you tell it to do, and do it well. It will not, however, tell you what to do with regard to temperature control, which some might see as decreased energy efficiency when compared to some other models.

True to its basic design, the Emerson Sensi lacks a color LCD screen. It also forgoes any sort of proximity sensing and location tracking inside your home. The goal with the Emerson Sensi is to let you set, change, and schedule your home’s temperature remotely – from anywhere – via your iOS or android smart phone app. You can alternatively choose to program the seven-day scheduler to help reduce heating and cooling energy costs. The Emerson Sensi is, perhaps surprisingly, compatible with Amazon Alexa, offering voice control convenience.


  • An easy thermostat to install with either the included C-wire or two AA batteries.
  • The matte, white frame is quite similar to a basic programmable thermostat, fostering familiarity and cutting down on intimidation.
  • Does what you have programmed it to do, as far as accurate temperature control is concerned.
  • Customizable, programmable seven-day scheduling option to help cut down on energy expenses.
  • Remote controllability via your iOS or android smart phone app.
  • Voice controllability with Amazon Alexa.


  • No color LCD screen. The matte, white frame is similar to a basic programmable thermostat, which doesn’t look very “smart.”
  • Does not operate temperature control outside the parameters that you set for the thermostat.
  • No proximity sensors or location tracking to learn from your movement and make subsequent heating/cooling adjustments.


  • Best Thermostat for Basic Features: Lifewire
Get it from Amazon: Emerson Sensi Wi-Fi Thermostat.

8. Carrier Cor 7-Day Programmable Wi-Fi Thermostat

Carrier Cor 7-Day Programmable Wi-Fi Thermostat 

The Carrier Cor Seven-Day Programmable Thermostat is a smart cost-conscious option. The Cor is an attractive, black rounded-corner square thermostat that looks well in the home. Features of the smart thermostat primarily include integrated wi-fi connectivity, automatic heating and cooling changeover, battery back-up, and vacation mode. Once programmed, the Cor’s seven-day schedule can be adjusted via a smart phone over wi-fi to maximize energy efficiency and temperature comfort in your home.

The display is backlit for aesthetics as well as functionality. It is a simple touchscreen to increase ease of use as well.


  • Affordability without sacrificing important features, compared to other smart thermostats.
  • Seven-day programming, with 48 periods per day available for scheduling, facilitates temperature comfort and cost savings.
  • Wi-fi connectivity, which allows you to check on and modify temperature as needed with any wi-fi connection via your smart phone.
  • Attractive, backlit touchscreen display.


  • Does not operate temperature control outside the parameters that you set for the thermostat.
  • No proximity sensors or location tracking to learn from your movement and make subsequent heating/cooling adjustments.
  • Not ENERGY STAR certified.


In your consideration of making your life easier by making your home smarter, a smart thermostat is up at the top of the list as a component that offers very real cost savings and comfort improvements. Consider the features of a smart thermostat that mean the most to you – maybe it’s the thermostat’s ability to learn your preferences, maybe it’s remote access and control, maybe it’s programmability. Whatever it is, you’re sure to find an excellent smart thermostat that will keep your household comfortable in any weather and season.