Convenience is just the beginning when it comes to the best smart thermostats. While they’re easy to use and can be automated so you don’t have to get up and adjust right before going to sleep, they also make your home more efficient, saving you money and keeping the temperature right where you want it when you want.
However, searching for the best smart thermostat is not as straightforward as you would think since there are two basic types. One is a little more basic and cheaper, meant to keep your entire space at a single setting, while the other, more expensive kind can customize each room to its own setting. Of course, that type is pricier as it requires extra installation of smart radiator valves and cooling vents.
Regardless of which you choose, they’re easy to use once installed, especially since you control them using a smartphone app or, in some instances, voice commands if you also own one of the best smart speakers.
Among the best smart devices on the market, smart thermostats can also be integrated into a smart home setting. If you want to create a morning routine, such as turning up the temperature automatically along with one of the best smart plugs (maybe for an electric kettle) and best smart lights, you can do just that using an app. That’s something you just can’t do with a regular thermostat. Plus, you can make multiple routines for when different people with different preferences are home.
To help you find the right option for you, we’ve applied our expertise and know-how as well as hands-on testing to bring you the best smart thermostats available right now, including from such well-known brands as Honeywell, Ecobee, and Google’s Nest. We’ve also linked out to individual reviews if you want even more information on any that pique your interest.
The best smart thermostats 2023
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The Nest Learning Thermostat (third generation) strikes the right balance between style and smarts, making it our pick for the best smart thermostat you can buy. It learns your routines and adjusts itself accordingly, meaning that over time your heating system can actually adapt to suit your needs without you having to do anything.
It also benefits from location-based features that track where your phone is and will turn the heating on or off depending on your location. But don't worry, it won't turn off the heating and leave your guests to freeze when you're out, as its built-in sensors can detect whether there's anyone at home.
The main criticisms of the Nest Learning Thermostat are that it doesn't offer zonal control. So while you'll be able to digitally control your property as a whole, you'll still have to adjust individual radiators manually.
Read the full Nest Learning Thermostat 3rd generation review
The Google Nest Thermostat was launched in the US in October 2020 and replaced the Google Nest Thermostat E as the brand's more affordable smart thermostat offering. However, the Nest Thermostat E is still available in the UK.
It builds on the Nest Thermostat E's white plastic design by being available in four different colored trims, which complement the screen's shade. However, as it's relatively smaller than most non-smart thermostats, you'll likely need an additional trim plate to cover up the holes when installing this model. Sadly it doesn't come with a stand as the Nest Learning Thermostat does, so it can only be wall-mounted.
It has the same simple-to-use app as the Nest Thermostat E, and once again, to keep the price low, it doesn't have any self-learning capabilities as the Nest Learning Thermostat does. It's also not compatible with Google's Temperature Sensor, so it only knows the temperature of the room it is located in.
Should I buy the Google Nest Thermostat?
If you want a smart thermostat that forms the basis of a smart home ecosystem you can build on, Hive Active Heating 2 is a good fit. The thermostat itself is a collaboration between Hive and Swiss designer Yves Béhar, who's responsible for everything from the August smart lock to PayPal's branding. That top-quality styling makes the Hive Active Heating thermostat something you'll be proud to have on your wall.
When it comes to the ecosystem, Hive offers a range of home security cameras, smart lights, and smart plugs, all of which can be controlled by the Hive app. While testing, we found that its simple interface and easy voice assistant integration made it a breeze to use. It's worth noting that, unlike Nest, there's no motion sensor built into the thermostat, and the mirrored finish is prone to fingerprints.
Read the full Hive Thermostat review
The Honeywell Evohome gives you total control over your home, with individual thermostats for each radiator enabling you to set an independent heating schedule for every room in your house.
It's difficult to grasp what a difference this feature makes until you've tried it for yourself. But, if you live in a house where different inhabitants prefer a different temperature, or if one room always seems hotter or colder than the others, this system will be a godsend. Moreover, it works with under-floor heating, too, so even if you have a large and complicated heating system, Evohome gives you total control over all of it via an app that's a pleasure to use.
The control panel and radiator thermostats aren't going to win any design awards, coming as they do in plain white plastic, but that's not really the point of the Evohome. It's expensive, too - as you'll need a smart valve for each radiator in your home. However, it's worth it for the granular control you get over your heating.
Read the full Honeywell Evohome review
OK, so not everyone needs another device with Alexa built-in. (We get it, guys, you can build Alexa into anything!) However, if you're in the camp of people with too many Alexa devices, the Ecobee 3 Lite is the perfect solution - it's just the smart thermostat without the smart assistant.
Easy to install and simple to use, we were impressed with the AC Overcool to Dehumidify feature, which utilizes your AC to lower indoor humidity.
That said, the Ecobee 3 is still compatible with all the leading smart home ecosystems. (Ecobee was the first smart thermostat compatible with Alexa, believe it or not.) But if you want the all the extras, like room sensors that can detect temperatures in certain spots in your home, you'll have to buy them separately.
Should I buy the EcoBee 3 Lite?
We tested the WundaSmart Starter Kit, which we feel brings something new to the stuffed smart thermostat market. It uses two gadgets in each room to precisely control the temperature: a stylish wireless thermostat and a smart radiator head, which replaces any existing TRVs (thermostatic radiator valves) on your radiators, allowing you to control them individually from the smartphone app.
It connects to your boiler via a module - or HubSwitch - and uses its own (low energy seeker signal RF) system to connect with the thermostats and radiator heads. It's really clever in doing this. It supports up to 30 rooms and 50 radiators, more than any other system.
You can schedule (via the app) when you want the house to be heated; override it to boost individual zones and detect when windows are open. It'll even learn how long your house retains heat and switch the boiler on or off if it deems it necessary. It's also compatible with Google Home and Amazon Alexa if you wish to control it with your voice.
Read the full Wunda WundaSmart review
As we've already mentioned, the Nest Thermostat E is still available in the UK. Unfortunately, it's made of white plastic, with a white coating on the plastic screen that can make it hard to see the information being displayed – but it does echo the design language of the original Nest Thermostat, so you'll be more than happy to have it on your wall.
As the Nest's smaller sibling, it benefits from industry-leading smarts, lacking only the most advanced features of the premium model, such as the self-learning capabilities. However, the app is simple to use too.
The Nest E is an excellent example of how to streamline a flagship product to make a cheap alternative without damaging the qualities that made the original great. Make no mistake, this isn't flagship quality for a bargain price, but it's great value for what it is.
Read the full Nest Thermostat E review
Love the idea of zonal heating control, but don't want to break the bank? Then Drayton Wiser is worth considering. You'll need a thermostat for each radiator in your home to get the most out of the system. Still, as thermostats are around a third cheaper than rival systems from Honeywell and Tado, the overall cost is more affordable.
It's simple to use and will switch the boiler on or off earlier than scheduled to ensure rooms in your home are at the temperature you want when you want them. It's also got Open Window Detection to help stop energy wastage by switching off the boiler if it detects a window has been opened and works with Alexa and Google Assistant.
However, it's not the most stylish of thermostats on the market, and there's no way to see the room's temperature from the radiator thermostat itself - you'll need to open the app on your smartphone. That said, it's hard to beat if you're on a budget and want complete control over your heating.
Read the full Drayton Wiser review
If available where you live, the Ecobee Smart Thermostat with voice control is well-worth auditioning for your smart home setup. Unlike any other entries on this list, the Ecobee4 comes with Alexa built right in. Thanks to a software update, the smart thermostat also offers access to Siri - Apple's voice assistant (although you will need a HomePod Mini in your home to process the requests).
That means that it is a great thermostat that can save you bundles on your energy bill each month and doubles as a conduit to Alexa and its 10,000-strong library of skills or Siri and all the home automation Apple's voice assistant can bring. It's easy to install, is self-learning, and will adjust your schedule accordingly as it learns how quickly your house heats up and cools down.
While Ecobee may not have the same clout that Nest has garnered in the last few years, it remains one of the best thermostats on the market, bar none.
Should I buy the Ecobee Smart Thermostat with voice control?
If you're on a tight budget, the Amazon Smart Thermostat is the ideal choice to remotely control your heating and cooling system, as it's almost half the price of other models on this list. Simple to use, the Amazon Smart Thermostat pairs with some Alexa devices in your home and uses your interaction with the best smart speakers to work out how it should adjust the heating. For example, saying Goodnight to Alexa will turn the heating off as it knows you're off to bed.
However, as Alexa isn't built-in to the smart thermostat, you will need to purchase a compatible smart speaker if you don't already have one. Amazon also says the more Echos there are in your house, the more accurate Alexa Hunches becomes, which could work out costly to get the most out of it.
There's no option for zonal control through radiator thermostats either, and the plastic design isn't stylish, but it's worth considering for those that already have an Echo or two.