Owning a smart thermostat is one of the best ways to monitor and automate your home heating or air conditioning. Now made by a number of reputable companies, smart thermostats are often compatible with leading voice assistants like Siri, Alexa, and the subject of today’s roundup, Google Assistant. They’re also pretty easy to install, are available in a ton of different shapes and sizes, and are backed up by some of the intuitive and user-friendly companion apps in the business.

All that being said, there’s a dizzying amount of smart thermostats out there, and not all of them support Google Assistant. And even if they do, there are some devices we wouldn’t recommend to our worst enemies. That’s where we come in though. As smart home experts, we’ve done the digging on all the best smart thermostats that support Google Assistant, and have compiled our findings in this helpful buying guide.

The best smart thermostats for Google smart homes

Why fix what isn't broken? That seems to be Google's approach to its fourth-generation Nest Thermostat, which has been out for a few years and remains at the front of the pack for most homeowners' needs. Installation doesn't get any easier; in fact, its novel "power stealing" technology means you probably won't have to call an electrician or retrofit a C-wire adapter onto many older HVAC systems. Initial setup can be tricky in a couple of minor ways, but once it's up and running, you'll appreciate the streamlined operation.

Granted, it's not the most high-end option out there, as it lacks Google's well-known smart learning algorithm and some other fancy features like external room sensor support. But if it's time you graduated from a dumb thermostat to a smart one, there's no better first option than Google's reasonably priced midrange model. As a final note, its support for the upstart Matter smart ecosystem makes it a great choice for future-proofing your setup, although it's not super useful quite yet.

Emerson's Sensi lineup of smart thermostats has always impressed despite its relatively low popularity, and the Sensi Lite is the latest and most refined member of the family. It's up there with the Google Nest in terms of installation ease, but instead of power stealing, it uses a pair of AAA batteries that should last about a year or so before replacement or recharging. Its setup process is also just a touch more streamlined than Google's, and owners routinely praise the app interface as being even better than Google Home.

It offers basic smart features like remote access, 7-day flexible scheduling, and the ability to lock on-unit controls so nobody messes with your thermostat when you aren't looking. It doesn't support remote sensors, but that's common in this price range. Essentially, the Emerson Sensi Lite is much like a traditional thermostat, but with added internet connectivity that allows for monitoring and adjustment from anywhere. At less than $100, you won't find a better deal.

For the first few weeks after installing the Nest Learning Thermostat, you'll need to operate it as normal, setting schedules and adjusting temperatures to your comfort. Pretty soon, though, its machine learning algorithms take over, learning just how and when you like your heating and cooling. After that, to quote infomercial and marketing legend Ron Popeil, you can basically just "set it and forget it," and you shouldn't have to make major adjustments except on rare occasions.

It's still the only smart thermostat with this capability, and you can bet your life that it and the rest of its vast smart features are as well-integrated into the Google Assistant experience as can be. It periodically steals just enough electricity from most common HVAC systems to keep its internal battery charged, so older systems without a C-wire likely won't have to install one (or even an adapter). The only real downside to the Nest Learning is its price, so if you're not interested in separate room sensors or long-term automated control, consider the standard fourth-gen Nest Thermostat instead.

They don't get much more affordable than the Wyze Smart Thermostat, one of the most streamlined entry-level options available. It's the least expensive option designed to support remote room sensors that can detect temperature, humidity, and motion, with each sensor costing only $30. A C-wire adapter for older homes comes with it, and as is customary with Wyze devices, pairing and setup are a breeze. You can also assign multiple users to the geofencing configuration, so when any of you come within three miles of your home, the heat or AC kicks on. Additionally, you can rely on the motion sensor to detect when somebody's around and return to Home mode.

Wyze's offering isn't the most advanced, but it's definitely the best value for tracking temperature, humidity, and movement in multiple rooms. Our only issue is the lack of IFTTT programming, which limits its integration with some third-party smart devices.

A quick glance at the Honeywell Home RTH9600 makes it clear it's not cut from the same cloth as other smart thermostats. Instead of a starkly minimalist design, its bright LED display offers a wealth of readout information, along with touch controls to tweak most of its many settings. For that matter, it offers the most comprehensive on-unit control of anything on the market, so it's great if you don't always want to resort to voice or app control.

It's one of our favorites partly because, in real-world testing, it kicks on and off quicker than most and maintains precise, consistent readings better than nearly all the competition. Unfortunately, similar to the Google Nest, it's also pretty expensive. And while it doesn't technically require a dedicated common wire, systems without one will need an adapter, as there's no battery or power-stealing functionality.

Sometimes all you need is barebones gear to get the job done. Such is the case with the Honeywell Home RTH6580, a smart thermostat that doesn’t look “smart” at all. Compatible with certain types of multi-zone heating and cooling systems, the Honeywell Home can be controlled using Google Assistant, Alexa, Microsoft Cortana, and other voice assistants. You’ll also be able to download the Comfort Connect and Resideo apps to control and customize the thermostat at home or miles away.

Other than four programmable hour blocks per day, there’s not much more in the way of features for the Honeywell Home. And depending on what type of HVAC system you have, you may need to invest in a C-wire kit to integrate the thermostat successfully. But if you’re looking to save some dough on a smart thermostat, and don’t need anything too fancy, the Honeywell Home should certainly be considered.

Not only does the Ecobee Premium boast a sleek design that looks great in any home, but its user experience also ranks among the best. And if you're looking for the most advanced features, including radar motion detection and airborne VOC air quality measurement, the Ecobee offers both. It's up there with the best in terms of on-device controls, and it even serves as a security system hub if you've opted for one of Ecobee's excellent smart security bundles.

If we had to pick one gripe, it would be that its temperature sensors aren't quite as precise as some others, and at over $200, it'd be nice if it were a leader in accuracy. Also, Google households will sadly miss out on the integrated smart speaker, which is hardcoded for use with either Siri or Alexa.

One of the best things about the Ecobee Enhanced Smart Thermostat is that it can be used as a home security hub. The catch is that your web-connected surveillance gear needs to be Ecobee products, but if you’re rocking some of the company’s smart cameras and motion detectors, the Enhanced thermostat can act as an arm/disarm command center for your existing Ecobee gear. So if you’ve been putting off a full investment in a smart security system, the Enhanced thermostat may be enough to put you over the edge.

Of course, you’ll also be able to use this Google Assistant-compatible thermostat as a standalone device for your HVAC system. Features include Ecobee’s eco+ suite, which grants access to capabilities like automatic temperature controls, routine learning, and energy monitoring right out of the box. You’ll also be able to download the Ecobee app to control and customize your thermostat, both at home and on the go.

If you want to keep multiple rooms toasty warm or cool and dry, the high-end Emerson Sensi Touch 2 is worth a look. Its feature set and precision are on par with the best, and the external sensor support (of up to 15 remote sensors) makes it ideal for managing large spaces. Its display is one of the best we've seen, with large, easy-to-read white numbers on a black background and simple, intuitive controls and notifications. Business owners (or territorial dads) will appreciate the one-touch lockout function that instantly secures the settings so nobody can mess them up.

However, there are a few programming quirks, like the lack of per-user geofencing rules. But hopefully, those can be fixed in the software as this relatively new device continues to get more popular. And it should get more popular because there are no major drawbacks as long as you can afford its high cost.

Wouldn’t it be great if we could automate our mini splits, portable air conditioners, and window AC units? Well, thanks to the brilliant minds at Ciello Breez, now we can! The answer to our prayers is the Ciello Breez Plus Smart Air Conditioner Controller, which allows you to integrate a number of non-HVAC cooling peripherals into Google Home, Alexa, Apple HomeKit, Samsung SmartThings, and IFTTT ecosystems. You’ll also have access to the incredible Ciello app, which you’ll be able to use to control your AC from anywhere in the world.

The app also includes schedule-building tools, zone-building options, and a number of other customizations. Do keep in mind that in order for the Breez Plus to work with your AC gear, whatever equipment you’re attempting to control will need to include an IR remote. Certain features may also not be compatible, such as fan speed controls or display on/off commands.

The top smart thermostats for Google Assistant smart homes

In many cases, Google Assistant and smart thermostats go together like French fries and ketchup, but you’ll want to make sure you’re also buying a web-connected temperature control hub that suits your needs. For most folks, we think the Google Nest Thermostat is more than capable of making temp control dreams come true, both at home and afar. It’s super simple to use, requires little in the way of initial setup, and can be controlled and customized through the Google Home app.

There's no shortage of premium options, either. For instance, the Ecobee SmartThermostat Premium competes directly with the Google Nest Learning thermostat, and some people prefer its interface. The Nest Learning, of course, boasts the only algorithm-driven learning methods that allow it to take control of your heating and cooling after a few weeks; this saves you additional money and keeps you even more comfortable without having to think about changing the thermostat.

When it comes to bang for your buck for most folks, though, the base model Google Nest Thermostat continues to take the cake. If you're looking for a more traditional thermostat user experience but with touchscreens and internet access, the Honeywell Home RTH9600 is a nice alternative to the Nest.

A note on common wire, or "C-wire" requirements

Most newer homes' HVAC systems include a common wire (or C-wire) that's always hot, so the thermostat's always powered on and ready to deliver commands. Most thermostats need a constantly hot wire like this, but some homes don't have a C-wire. This isn't a huge problem, as pretty much every thermostat that needs a C-wire comes with or offers an optional C-wire adapter. In that case, you'll still have to do a little bit of electrical work.

Only work on your home's electrical system if you're comfortable, and take all important safety precautions. It's better to hire an electrician than get electrocuted.

That said, some thermostats advertise that they don't need a C-wire. That usually refers to the aforementioned adapter, which you may or may not have to purchase separately.

The only three worthwhile models that legitimately don't require a constantly hot wire are Google Nest, Google Nest Learning, and Sensi Lite. The two Google models steal small amounts of power from the active HVAC wires often enough to keep their internal batteries charged, and the Sensi Lite runs on a pair of AA batteries. So if you really don't want to mess with hot electrical wiring, get one of those three.