Heatable uses cookies to give users the best possible experience.

View Policy

Black Friday Boilers
We've knocked £100 off, everything.

COVID-19 Notice
We're still installing boilers, safely. Read more.

Best Smart Thermostats in the UK in 2021

From smart to stupid, here, we take a deep-dive in to the world of smart thermostats from leading brands such as Nest, Hive, Honeywell & more.

Are you wanting to install the very best smart thermostat into your home?

...you wouldn't want to install a stupid one, would you?

Nest Smart Thermostat vs Hive Smart ThermostatIn this guide, we are going to explore some of the most popular smart thermostats in the UK, compare key features between them and find out why some are a little smarter than others. 

You have probably heard of the likes of the Hive smart thermostat and the Nest smart thermostat, which are the 'premium' market leaders, but there are some budget-friendly options too. 

Spoiler:  For those who can't be bothered reading the next 4,000 words, just buy a Nest Smart Thermostat

Factors we considered when choosing the best smart thermostats in the UK 

A smart thermostats main purpose is to help you control and monitor your energy use, you want it to be user-friendly, easy to install and genuinely useful in helping you to keep on top of your energy consumption and hopefully save you some money in the process. 

This blend is where the best smart thermostats perform well, while the less smart ones come out looking a little dumb.  

With this in mind, we have considered the following factors when ranking the thermostats, we analysed: 

  • Ease of the installation process 
  • User-friendliness of the thermostat 
  • The overall usefulness of the features offered 
  • The ability of the thermostat to save you time and money on your energy bills 
  • Compatibility of the thermostat with virtual assistants such as Alexa and Google Home 
  • The price range of the smart thermostat 
  • Customer reviews and reputation 
  • Warranty period the brand offers 

Best Smart Thermostats in the UK

#1 Nest Smart Thermostat

Nest Smart Thermostat

The Nest 3rd generation smart thermostat is the go-to name when it comes to smart thermostats and with good reason, this brand (now owned by Google) continues to drive innovation in the smart home space and their smart thermostats are leading the way. 

  • Price*
    £250 for the standard unit 
  • Wireless
    Yes (but, can also be mounted on stand with 3 pin plug)
  • Warranty
    2 years standard (5 years with NestPro Installation) 
  • Easy DIY
  • Subscription Required

*as of September 2020

Nest Features

Nest smart thermostat has a range of smart features that help you to save energy and money and streamline your energy use, these include the following: 


Smart, auto learning features

Nest Auto Learning Thermostats

Nest learns from you, by monitoring your heating use it automatically adjusts and syncs your heating with your behaviour, knowing the times of day you use your heating, as well as the ideal room temperatures you prefer.

It also adjusts based on your home’s insulation and the weather outside, enabling Nest to create a personalised schedule just for you and your property. 

Control from anywhere 

Nest Smart Thermostat AppThe Nest mobile app means you can easily and conveniently control your nest thermostat wherever you are, allowing you to turn up your heating when you are on your way home, so it’s nice and warm for your arrival. 

Location detection (a.k.a Geo fencing)

Nest Geofencing

Using the location of your mobile, it can accurately detect if you are at home and turn the heating off or down if you are out, helping to avoid wasting money heating an empty property. 

Open Therm technology 

Open Therm Thermostat

The latest Nest thermostats also use open therm technology, helping you save even more energy. This is an advanced algorithm that can modulate your boiler’s heating temperature, allowing your boiler to use less gas to reach the temperature set by the thermostat. 

Nest Protect

Nest Protect

A carbon monoxide leak from your central heating boiler or heating system can be deadly, so it’s great to know the Nest can work in conjunction with the optional Nest protect smoke alarms to turn your boiler off should it detect a CO leak.

Can Nest thermostats save you money on your heating bills? 

Nest states that the average UK customer can save between 8.4% – 16.5% on their heating bills by using a Nest thermostat. 

Although there is no independent verifiable data to confirm this, it is certainly an impressive claim. 

With that said, the Nest does monitor your behaviour and adjust your heating as necessary, so there is little doubt that it will help to reduce your energy use and therefore save money.  

Looking to pay for your new boiler monthly? Refer to our boilers on finance guide for more info. 

Nest thermostat device compatibility & connectivity 

A major concern of many curious thermostat hunters is the compatibility – can it be used with your other devices? 

Thankfully, the Nest thermostat app is compatible with standard digital devices including: 

  • Computers
  • Mobile phones
  • Tablets

But what about connectivity? For example, can the Nest be used with Alexa?

Nest Thermostat Compatibility

Again, Nest is completely adaptable and can work with the most popular virtual assistants, including: 

It is worth noting that the Nest does have a few basic requirements to operate including a Wi-Fi connection, as well as a phone or tablet with iOS 8 or later, or Android 4 or later. But this is the same case for most smart devices. 

Will the Nest thermostat work with your boiler?

It's good news in that department, too.

The Nest thermostat is compatible with most heating systems including the following: 

  • Combi boilers, biomass, system boilers, immersion heaters,  and heat-only boilers
  • Air source/ground source heat pumps
  • Underfloor heating systems
  • Zoned heating/multiple zones
  • Domestic tanks for hot water
  • Systems enabled with Open-Therm technology

However, if you want to make doubly sure, you can always check your unit’s compatibility on the official Nest website, simply enter your appliances model number and it will give the answer.

You can do that, here

Nest thermostat warranty

When buying any new product, the warranty period is an important consideration, as if something does go wrong, you want the reassurance that the manufacturer will help you repair it and get it back in working order. 

Nest Thermostat Pro InstallationNest offer a 2-year warranty on the smart thermostat, but if you opt to get your Nest installed by a Nest Pro i.e. a professional and vetted Nest installer, you will be entitled to an additional 2-year warranty, so 5 years in total. 

Nest customer reviews

Amazon Nest Thermostat Reviews

Customer reviews are a great place to look to get the honest views of real users of the product. They can be incredibly revealing, hence why we have decided to make them part of our thermostat analysis. 

Nest have thousands of customer reviews online on various platforms such as their Google and Amazon, averaging between 4 and 5, which is remarkable considering they must have sold tens of devices, at the very least. 

The most frequent feedback on the Nest thermostat is how much time and money it has saved via its geofencing capabilities, as well as the ease of installation. 

Nest thermostat design 

Nest Thermostat DesignThe simplistic and stylish design of the Nest makes it stand out from its rivals by a clear mile. The circular design and sleek, high-resolution digital interface free from wires and buttons make it look good almost anywhere. 

The Nest can be either wall-mounted or placed within a stand (available for an additional £30 - not included as part of the standard package).  

Want to have your boiler moved to a different location? Check out our "cost of moving boiler" guide.

Can you install a Nest thermostat yourself? 

The Nest smart thermostat can be installed by yourself, or if you prefer you can use a Nest Pro Installer. This is a professional Nest installer that has been vetted and accredited with specifically installing the Nest device. 

If you do opt to have the Nest installed by a Pro installer, you will be entitled to the extended Pro warranty, so it is certainly worth considering.

Nest smart thermostat: Heatable's verdict

Google Nest Thermostat Logo

There is little doubt that the Nest’s popularity reflects its superiority compared to rivals. In our view, it is award-winning design currently has no competition, but its ease of installation, wireless capability and innovative features combined make this the best smart thermostat available in the UK. 

In maybe a little pricier than some of the other devices, but the 2-year warranty and the fact that it has got all the necessary bases covered makes it well worth the extra investment.

#2 tado° V3+ smart thermostat

Tado Smart Thermostat

Selling in the UK since 2015, tado° is offered as a complete package and the starter kit can be purchased with additional add ons, such as smart radiator controls

The brand has a range of exclusive features not offered by rivals including open window detection and weather adaption. The best part? As of November 2020, they are rated at 4.3 (Excellent) on Trustpilot, outperforming competing devices such as Nest and Honeywell. 

Having one of the highest ErP Energy Efficiency Classes of 8, this device is a solid option for those looking to take complete control over their heating. In fact, this makes it the most efficient out of any of the other devices we reviewed.

You can read our complete tado review here. 

  • Price*
  • Wireless
  • Warranty
    2 years
  • Easy DIY
  • Subscription Required
    For some features 

*as of September 2020 

tado° V3+ features

The tado° V3+ home kit comes with a range of innovative and exclusive features, as well as smart radiator controls and smart thermostat, which allows you to utilise the concept of zonal heating. Ultimately this device helps you to reduce energy wastage and save more money on your heating bills. 

Zonal heating control 

The tado° V3+ app can be accessed from your mobile or other devices, allowing you to control the heating remotely at any time. 

Tado Home Starter Kit

The tado° V3+ home kit includes the smart thermostat, wireless receiver and the internet bridge. However, additional radiator controls can be purchased, which allow you to control the heating of your boiler, as well as the radiators in each room, letting you adjust the heating output in every room that has one installed. 

This allows you to take advantage of the concept of zonal heating i.e. instead of heating your entire house, only heat the zones or rooms you are using. This is an effective way to reduce your energy use and make some big savings.

Smart scheduling 

Nothing new for a smart thermostat, but certainly worth mentioning. From the app, you can set a 7-day schedule, adjusting the temperature and heat output based on the time of day and whether you will be in the house or out. You can easily adjust remotely should your plans change, which is always handy. 

For comparison, the Hive smart thermostat doesn't adapt to weather at all (which is really inefficient and puts them at Class 4 ErP - the same as a standard RF control). 


Tado Thermostat Geofencing

Are you ever in a rush and forget to turn the heating off? tado° V3+’s geofencing feature tracks you based on your mobile’s location, so should you leave the house your heating will be turned off to avoid wasting energy and money. 

Same goes for when you are returning home, this feature will detect your journey home and get your home to the temperature you like before you arrive. 

Tado Geofencing Subscription Although, it is worth mentioning that both their geofencing and open window detection features are not automated unless you pay for a monthly subscription. You can still use them, but they must be adjusted manually, in which case you will receive a push notification to action. 

Smart reporting 

Perhaps one of the tado° V3+’s most innovative features is the smart reporting, which you can access from inside the mobile app. It provides a range of useful data that you can use to monitor your heating use and modulate your behaviour to make further savings if you desire. 

Tado Reporting

The reports present the data in a colourful and easy to understand format, which includes heating and weather activity, how much you have saved to date and even when you had the windows open.

Opentherm Technology  

Just like the Nest, the tado° smart thermostat also features opentherm technology, as well as the digital BUS on Worcester, Vaillant and Viessmann. No other thermostat device offers this broad compatibility. 

tado° V3+ warranty 

This brand has decided to compete with Nest on warranty period and offer cover for 2-years, which is great for a relatively new brand. 

tado° V3+ device compatibility and connectivity 

Like other smart thermostat brands, the tado° is controlled via the mobile application that can be accessed via PC, tablet, or mobile phone. 

Tado Thermostat Compatibility

With regards to connectivity, you can connect to some of the most popular virtual and smart home assistants including the following: 

  • Amazon Alexa
  • Apple HomeKit (Unlike Nest)
  • Google Assistant

As can be seen, the tado° is compatible with all of the most popular virtual assistants. In fact, tado° is more compatible with the common smart assistants than Nest (which has no Apple integration - obviously, a big miss when Apple is the most popular phone) and the same as Honeywell's T6. 


tado° V3+ design

The tado° V3+ thermostat is a contender for the best-looking thermostat award, thanks to it’s contemporary and clean looking exterior it looks like it was created by a Californian company with an apple-shaped logo. 

Tado Geofencing Subscription

The thermostat’s digital interface is incredibly subtle and the brand has opted for a simple digital temperature display as opposed to Nest’s super high resolution and large display, which makes sense since all the important data can be viewed within the app. 

tado° V3+ customer reviews 

The tado° V3+ Smart home starter kit has great reviews overall and on sites like Amazon and Google has a solid 4 stars. 

As of November 2020, they had a Trustpilot score of 4.3 (Excellent), exceeding all rival devices. 

Tado Thermostat Reviews

Customers are extremely positive about tado° V3+, with many users praising how much energy and money it is helped them save on their energy bills.

The most notable negative reviews are those owners complaining about the company changing their automated geofencing and open window detection features to a monthly subscription pricing model. 

Can you install tado° V3+ yourself? 

One of the biggest advantages of the tado° V3+ is their relatively simple DIY installation, that means around 95% of customers have managed to avoid the costs associated with a professional installation.  


The best part? tado° offer some incredibly user-friendly and visual, step by step installation guides on their website. One for the thermostat installation and a separate one for the installation of their radiator thermostats. 

tado° V3+ smart thermostat: Heatable's verdict

The tado° V3 has some genuinely useful features, such as allowing you to monitor your energy use via an attractive report interface and control your heating room by room via the radiator thermostatic valves. 

Tado Thermostats Logo

It is also a great option for those who want a relatively quick and easy DIY installation. 

The tado° V3+ also has some of its very own unique features that set it apart from the competition, including open window detection and adaptation to the weather forecast. As of November 2020, they had a Trustpilot score of 4.3 (Excellent), exceeding all rival devices. 

Curious to know which boiler brand performed worst? Find out in our report of the worst boilers

#3 Hive Smart Thermostat

Hive Smart Thermostat

The Hive smart thermostat is the creation of energy giant British Gas and as a result, many are now familiar with the brand, due to its huge marketing campaign in recent years. 

  • Price*
    £179 for the standard unit 
  • Wireless
    Yes (but, can also be mounted on stand with 3 pin plug)
  • Warranty
    1 year
  • Easy DIY
    Yes, knowledge of basic wiring required
  • Subscription Required

*as of September 2020

Check our new boiler costs guide and use our boiler size calculator if you want to get a better understanding of how our fixed price boiler quote tool works. 

Hive's features

Unlike Nest, Hive does not have as many features and it is lacking in terms of compatibility, but without further ado, here is our full analysis: 

Set daily schedules 

Hive Thermostat Daily Schedules

Hive smart thermostat allows you to set your own personalised daily heating schedule manually using the Hive mobile app. You can set up to 6 individual daily slots, allowing you to easily adjust your heating based on your individual needs, helping to make further savings on your bills. 


Hive  Geofencing

Like the Nest, using the location of your mobile, the Hive can tell when you have left your home and if the heating has been left on, it will send you a reminder to turn it off. 

Frozen pipe protection 

Hive Thermostat Frost Protection

Frozen pipes are a common issue during the winter months, so Hive’s frost protection can be incredibly useful. If the temperature outside drops below 7°C, frost protection will be activated, preventing your pipes from freezing. 

Hive thermostat device compatibility & connectivity 

Just like Nest, Hive can be connected and used on, most devices including computers, tablets, and mobiles. 

Hive Thermostat Compatibility

In terms of connectivity, it can be connected with the most popular virtual assistants including Amazon Alexa and Google home. 

Is your boiler leaking or losing pressure? Use our quick and easy tool to get your fixed price boiler replacement. 

Will Hive work with my heating system? 

Since British Gas are quite familiar with the British market, Hive Active Heating will work with most heating systems in the UK, including the following:

  • Gas & LPG Boilers 
  • Oil Boilers 
  • Electric Boilers 

You can always check whether your specific new boiler replacement will be compatible with Hive on the official website.

British Gas promises to refund your purchase if it can’t be installed in your home due to compatibility issues (within 14 days of receiving the product).

Control your heating with Hive & Alexa 

Hive Amazon Alexa

Every Hive thermostat comes with a free Amazon Echo Dot*, allowing you to control your heating with your voice. For instance, if you feel like your heating needs a little boost, you can simply say “Alexa give my heating a boost”, in which case Hive will provide you with an extra hour of heat before turning off. 

as of September, 2020

Hive thermostat design 

Nothing quite compares to the Nest’s sleek and award-winning design, unfortunately not even the Hive. 

The box-like design looks pretty good as far as thermostats go, but it looks quite dated next to The Nest’s high resolution, digital interface. 

Although, you can choose a custom thermostat frame designed by Dulux to match the colour of the décor of your home, which is a truly pointless, but nice touch. 

Hive customer reviews

Amazon Hive Thermostat Reviews

Overall, Hive Smart thermostat has some very positive customer reviews, but far less than Nest, maybe reflecting a difference in popularity and sales figures between the two products. 

Notable complaints reference the poor customer service they received when something went wrong. 


Hive thermostat warranty period 

Unlike Nest’s impressive 2-year warranty, the Hive is only available with a 1-year warranty. 

Can you install the Hive thermostat yourself? 

The Hive thermostat can be installed by yourself, but you will need to have some knowledge of wiring it to the boiler, so it is probably not the best option for most people. 

British gas recommends a professional install carried out by one of their gas safe engineers, which takes around an hour to complete, after which you will receive an instructional tutorial by the engineer. 

Hive smart thermostat: Heatable's verdict

There is no doubt that the Hive is the best and now on the 3rd generation, this brand shows no sign of stopping when it comes to innovating and improving the smart home technology they offer. 

Hive Thermostat Logo

Benefiting from the best design by far that includes a high resolution and easy to use interface, this device has all the features you could need to keep tabs on your energy use. 

The only downside is the price, at £179 it is positioned as the premium option but who can blame them? DIY installation, crisp design and all the features you could need to make it the best smart thermostat to own.

#4 Honeywell T6 smart thermostat 

Honeywell T6 Smart Thermostat

The Honeywell brand has been a giant in the heating and cooling industry for decades, themselves boasting that they help put a man on the moon and made air travel safer, so it’s not surprising that they also offer their smart thermostat. 

  • Price*
  • Wireless
    No (but, can also be mounted on stand with 3 pin plug)
  • Warranty
    2 years
  • Easy DIY
  • Subscription Required

*as of September 2020

Honeywell T6 smart thermostat features

Honeywell does not have as many features as the Nest, but it does have all the major perks you would expect in a smart thermostat, these include the following: 


Honeywell T6  Geofencing

The geofencing or location-based temperature control is just like features offered by rivals. The T6 smart thermostat allows you to control it remotely using the Honeywell application on your mobile or other devices, allowing you to adjust the temperature on demand. 

The T6 also uses your phone's location to determine if you are at home or not, adjusting, as necessary. 

For example, if not home, it can turn off to save energy and will start to heat your home when it detects you are on your way back home. This feature is standard for most smart thermostats, albeit very useful. 

Adjustable, programmable & flexible 

Honeywell T6 Thermostat Daily Schedules

The T6 can adjust the temperature of your home to meet your heating demands, no matter what time of day, how insulated your property may be or the temperature outdoors.  

The best part is that you can set a 7-day schedule based on your specific routine, helping you to save energy and money and ensure the temperature is just how you like it when you like it. 

The T6 offers you maximum flexibility, enabling you to adjust your schedule remotely from the Honeywell app at any time, should your plans change. 

Honeywell T6 device compatibility and connectivity 

As standard, the Honeywell T6 thermostat is compatible with everyday devices including computers, phones, and tablets. 

Honeywell T6 Thermostat Compatibility

You connect to the device using the Honeywell Home App, which is the hub of all other smart home products offered by Honeywell, which includes their thermostats, leak detectors, TVs, and security systems. From here you can control the T6 and adjust the settings as required.

The T6 can be connected to the most common virtual assistants and smart home interfaces, including the following: 

  • The Apple Homekit 
  • The Apple Watch 
  • Google Home 
  • Amazon Alexa
  • IFTT

Honeywell T6 thermostat warranty period 

Honeywell offers a 2-year warranty on their T6 smart thermostat, which is reasonable and standard for the thermostat market. 

Honeywell T6 thermostat design 

Honeywell’s T6 offers a sleek, modern design and a user-friendly digital interface that provides the subtlety that many people look for. 

Honeywell T6 Thermostat DesignIt is certainly one of the better-looking smart thermostats on offer, right up there with the Nest, but somehow the Nest’s timeless design and large high-resolution interface have a lasting impact that the T6 does not quite achieve. 

Honeywell T6 thermostat customer reviews 

Honeywell has been a leading brand in the heating and cooling space for years, so it is not surprising to see their smart thermostat earn itself a solid 4 out of 5 on average. Seen on sites like Amazon. 

Honeywell T6 Thermostat Reviews

Unfortunately, the negative reviews are concerning with one self-described HVAC technician referencing the lack of a temperature differential within the unit, causing it to turn on and off every few minutes to maintain the chosen temperature, which he notes will cost a lot of money. 

Other than that, most reviews are positive and frequently reference the units ease of connectivity with other devices and virtual assistants and its user-friendliness. 

In need of a new boiler? Learn all about combi boilers in our what is a combi boiler guide. 

Can you install the Honeywell T6 yourself? 

The T6 does not have the same wireless capability as other thermostats, so needs to be wired directly into your boiler, therefore, it is designed with professional installation in mind. 

Honeywell T6 smart thermostat: Heatable's verdict 

Honeywell has been around for over 100 years and has built a solid reputation for its high-quality range of heating and cooling products, so their brand is certainly one that is easier to trust. 

Honeywell Logo

Their smart thermostat has all the essentials, allowing you to easily control and modulate your home heating for maximum efficiency. 

Unfortunately, they do require professional installation, but for just £150 they are the ideal budget-friendly option.

Our two-pence on smart thermostats 

We hope our smart thermostat analysis has helped you see how the most popular brands in the UK currently compare and draw your conclusions.

As made clear in our thermostat reviews, our current recommendations are as follows:

If you would like to have more control of your energy use and save money on your bills, a smart thermostat is a great way to start.

In fact, according to Energy Saving Trust, installing heating controls could save you as much as £75 a year. 

New boilers installed by Heatable are compatible with smart thermostats including Nest, which you can now order with your boiler.

More advice

New boiler deals

Buy your new boiler, better

Get a fixed price on a Which? Best Buy in minutes

Heatable is registered in England and Wales No. 08804726 (VAT No. GB205805920 ). Trading address is 1 Station Road, Great Sankey, Warrington, Cheshire, WA5 1RH. Heatable acts as a credit broker (not as a lender) and offers credit products through a panel of lenders. Heatable is authorised and regulated by the Financial Conduct Authority (reference no. 805259).

[1] Price based on a like for like combi swap in a 2 bed, 1 bathroom terraced home with a standard flue

[*] Installation dates are subject to installer availability

[ยน] only available on combi boiler installations

Financial Support: If you are in receipt of certain benefits, you may be entitled to claim a free boiler grant.