Now that we're in the dog days of summer — and temperatures around the globe are hotter than ever — it's likely you're running your air conditioner more often to keep things cool inside your home.
If you want to make sure you're not spending all your money on your electricity bill, one of the best smart thermostats can help. It can detect when you’re not at home, so it'll turn down the heat, but then have your house ready at the right temperature for when you return. They can also analyze your patterns and the weather and make suggestions as to what temperature you should set to reduce your energy bill.
But, which one should you choose? We’ve tested a number of the best smart thermostats in our own homes to find out how they perform under real-world circumstances. If you don't have central air, you'll want to check out our guide to the best smart air conditioners.
Smart thermostats range from around $250 to less than $100 — we've tested models in all price bands — but if you have your eye on a more expensive model, you should check with your local energy utility; many offer rebates and other incentives to install a smart thermostat. Under the Inflation Reduction Act, you may also be able to claim a tax credit for the purchase of a smart thermostat, as well as other energy efficiency improvements.
Here are the best smart thermostats we've tested.
The quick list
A redesign gives the Ecobee a much-needed makeover. But its features — including a remote sensor, built-in smart assistants, and air quality monitor — is what sets this device apart.
Best Nest Thermostat
Best Nest Thermostat
It's a bit long in the tooth, but the Nest Learning Thermostat still looks great, and is really clever in how it analyzes your patterns to optimize the temperature in your home.,
While it only works with Alexa, the Amazon Smart Thermostat uses Alexa Hunches to keep your home at the optimal temperature. We also liked its clean design and the fact that it's less than $100.
Best cheap Nest
Best cheap Nest
The Nest Thermostat isn't as magical or smart as the Nest Learning Thermostat, but it still works well, and costs half as much.
Best no-frills smart thermostat
Sometimes, all you need are the basics. This $100 model is lacking in the looks department, but it works well, and you can control it remotely from an app.
The best smart thermostats you can buy today
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The best smart thermostat overall
With its zinc case and much larger touchscreen, the Ecobee Smart Thermostat Premium looks much better than previous generations — on a par with the Nest Learning Thermostat — and is even smarter on the inside. Now, it has an air quality sensor built in, so you can see if you need to open a window or turn on a fan. The huge display also lets you look at the weather forecast for the week.
As before, the best part of the Ecobee is its remote sensors, which make it easier for you to manage the temperature in your entire home. The Ecobee also has Alexa built in and, if you have a HomePod or HomePod mini, can also talk to Siri through the thermostat. The built-in speaker is still not great for listening to music, but it's a way to get a smart speaker in a room where you don't want to place an Echo Dot.
Read our full Ecobee Smart Thermostat Premium review.
Best Nest thermostat
The Nest Learning Thermostat was the original smart thermostat, and its classic design still stands out among the competition. The third version of this Google-owned thermostat has a larger and sharper display than its predecessor. Like before, the Nest Learning Thermostat learns your behavior over time, so it can automatically change the temperature when someone comes home.
While the Nest thermostat has a retro-style circular design, its brushed stainless steel finish and turning mechanism all feel premium. Plus, it comes in a variety of finishes, including Brass, Polished Steel, Copper, and White, so it can more easily fit in with your home decor. This thermostat combines the best of the past with the future, and is one of the best smart thermostats that's Google Home compatible.
Read our full Nest Learning Thermostat review.
Best budget smart thermostat
The Amazon Smart Thermostat isn't as intelligent as the Nest or the Ecobee models above, but it does use Alexa's hunches to gain some smarts in knowing when to turn the temperature up or down. At $59, it's one of the most affordable smart thermostats around, and we found it very easy to install and program in our home. It has a simple but clean aesthetic that fits in almost anywhere, too.
Keep in mind that you'll need a C-Wire, or else you'll need to purchase a C-Wire adapter (sold separately) for the Amazon Smart Thermostat to work. Unlike the Nest and Ecobee models, there are no remote sensors for you to monitor the temperature in other rooms. And, of course, it only works with Alexa. But, at this price, those are compromises we're willing to overlook.
Read our full Amazon Smart Thermostat review.
Best cheap Nest thermostat
If you want a Nest-like experience for half the price, the simply named Nest Thermostat is the best option. While it doesn't have a rotating bezel, it does have an intuitive touch-sensitive strip along one side, and an attractive mirrored front that begs you to touch it (but will leave all sorts of fingerprint smudges if you do).
However, for the lower price of the Nest Thermostat, you are giving up two key features: This thermostat doesn't "learn" your patterns and adjust the temperature accordingly. Nor can it work with remote sensors, so it won't be as helpful if you have a room that stays particularly cold or hot. But it's available for around $100, and has a feature that its more expensive brother doesn't: Thanks to its Matter integration, the Nest Thermostat can also be used with HomeKit, Apple's smart home platform.
Read our full Nest Thermostat review.
Best no-frills thermostat
The Honeywell RTH6580WF Wi-Fi Thermostat is the best smart thermostat for those on a budget, because offers much of the same functionality as higher-end models, but costs less than $100.
Like the Nest and Ecobee smart thermostats, you can control the Honeywell RTH6580WF from your smartphone, and connect it to Alexa and Google Assistant, which not only lets you change the temperature with your voice, but link it with other smart home products. In addition, the Honeywell Home ecosystem includes a wide range of partners, including Arlo, Apple HomeKit, SmartThings, Lutron, Kwikset Kevo, and more.
What you don't get with the Honeywell RTH6580WF are the stylish looks of the Nest, nor the remote sensor capabilities found with the Ecobee. But, if all you're looking for is a smart thermostat that delivers on the basics, this is a great model to consider.
Read our full Honeywell RTH6580WF review.
Best cheap Ecobee
Like the Ecobee SmartThermostat, but are looking for something less expensive? The Ecobee 3 Lite has many of the same features as Ecobee's top-end model, but costs $80 less.
The Ecobee 3 Lite has a color touchscreen, intuitive interface and deep smart home integration. Plus, Ecobee also updated the Lite model to work with remote sensors so you can set it to keep the heat on until a room in a far corner of your house reaches a certain temperature. However, you have to purchase those sensors separately.
The Ecobee 3 Lite works with Apple HomeKit, Google Assistant and Alexa, but unlike the Ecobee SmartThermostat, Amazon's voice assistant isn't built into the thermostat. It also doesn't support HVAC accessories, so you can't use it if, say, you have two-stage heating and cooling. It also lacks eco+, which learns your schedule and recommends changes to help save you money.
Read our full Ecobee3 Lite review.
How to choose the best smart thermostat for you
If you’re in the market for a smart thermostat, there are a number of factors you will need to consider.
How much do you want to spend on a smart thermostat?
- $200 plus: For this price, you will find the more premium models from Ecobee and Nest. These will come with the most features and tend to look the most impressive as well. If your home has two-stage heating and cooling, then these will be the best smart thermostats for you. This is because lower value smart thermostats tend not to support more complex HVAC systems.
- $100-$200: Most smart thermostats will fall into this price range and their capabilities will be sufficient for most homes. However, you won’t have access to some of the premium features such as voice assistants or two-stage heating.
- Less than $100: These models will cover the basics and can still connect to your smartphone. But, they’re not as easy on the eye, and often aren't as "smart": they don't have features that can learn your comings and goings. However, you can often link these to other smart home systems that can sense when you're home and when you're not.
How big is your house?
Another factor to consider is the size of your house and whether any rooms struggle to reach the ideal temperature. If this is the case, you may want to consider a model which comes with, or supports, a wireless sensor, such as the Ecobee.
The better smart thermostats can analyze your heating and cooling, and will suggest slight changes to your pre-set temperatures that could save you money. For instance, it might suggest turning the heat down by a degree or two, or turning the A/C warmer; while you'll be unlikely to tell the difference, it could reduce your utility bill over the long run.
You should also look into other features of interest, such as geofencing, where you can set the ideal temperature for when you’re out of the house and for when you return. It’s also worth checking if the smart thermostat is compatible with Alexa, Google Assistant, and Siri too.
While most smart thermostats will work with Alexa or Google Assistant, fewer will work with HomeKit. However, that could be changing this year as Matter support is added to more devices. This new interoperability standard will make it easier for smart home devices to connect and talk to one another, which should, in theory, open up HomeKit to a greater number of gadgets.
How we test smart thermostats
The best way to test a smart thermostat is to use it first-hand in your home, and that’s exactly what we do. We assess how easy it is to install and set up, which is important considering most smart thermostats are designed to be installed by the homeowners themselves.
During the trial period, we put each smart thermostat through a set number of tests to see how it handles different situations. We consider how well it responds to changes in temperature and whether we can easily create a schedule. If it comes with an app, that’s also assessed for navigation and effectiveness. The same goes for connectivity to smart home hubs or devices; if it works with Alexa or Google Assistant, we check its performance there too. Any additional features are trailed as well so we can get a full picture of the product.
How to install a smart thermostat
For the most part, installing a thermostat, smart or not, is a fairly easy process, usually involving nothing more than a screwdriver and about half an hour of your time. Here's our guide to how to install a Nest thermostat; however, the procedure is similar for almost any thermostat.
Many smart thermostats require a "C" Wire, which provides a steady stream of power to the thermostat. If you're living in a house with a central AC system, chances are you will have a C Wire. If you don't, you'll have to install a C-Wire adapter kit, which will either be included, or will be available for purchase, by the same company that makes your smart thermostat. Be sure to read our guide on why you need a C-Wire and what do you if you don't have one.
Smart thermostats: Frequently asked questions
What temperature should I set my thermostat?
The answer may surprise you, but according to the U.S. Department of Energy's Energy Star program, you should keep your home at 78 degrees while at home, 82 degrees when asleep, and 85 degrees when away. Even if you set your temperature lower, you're unlikely to feel that much of a difference, and you'll be using a lot more energy, according to the DoE.
Can I get a Nest thermostat for free?
Depending on your utility provider, you may be able to get a Nest thermostat — or some other smart thermostat — for free or for a reduced price. Some utilities also offer rebates for smart thermostats, so it's worth checking before you make a purchase.
Do I need an electrician to install a smart thermostat?
In most cases, you can install a smart thermostat yourself, and should only take about a half hour of your time. However, it's important to follow the manufacturer's instructions, and be sure to turn off the power to the thermostat before starting, to avoid hurting yourself or damaging either the thermostat or your HVAC system. And, if you're unsure of anything, it's best to consult a professional.
What's the difference between a programmable thermostat and a smart thermostat?
A programmable thermostat lets you create a schedule that will increase or decrease the temperature in your home at set times.
A smart thermostat will also let you create a schedule, but it will also let you control it remotely from your phone. Some smart thermostats can also sense your presence in your home — or even a particular room — and then adjust the temperature accordingly. Last, smart thermostats will also connect with other smart home devices so that they can work in concert with each other.
Do smart thermostats work if the power goes out?
Unless your smart thermostat has a battery backup, it will stop working if your power goes out. However, it stores all the pertinent information — such as your heating and cooling preferences and your Wi-Fi — so that you don't have to reset everything when your power comes back on.
Is there a monthly fee to use a smart thermostat?
Typically no. None of the thermostats listed in this guide require a monthly fee to use them, and they're all very good options. Don't waste your money on a smart thermostat that requires you to pay a monthly subscription.
More from Tom's Guide
Be sure to check out our other smart home guides to save you money and keep your house safe and secure.