Smart Thermostat Guide

What is a smart thermostat?

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Our handy guide outlines everything you need to know about 'smart' thermostats

Hand adjusting smart thermostat

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A smart thermostat allows you to control the heating of your home remotely, from your smartphone or tablet.

It can be programmed so your heating comes on at a certain time or at a certain temperature, with some models being able to intelligently work out how long it will take to heat rooms in your home.

What makes smart thermostats ‘smart’?

Smart thermostats do away with the inconvenience of walking into a freezing cold house because the heating wasn’t programmed to come on. Instead, you can use your phone or tablet to power up your home remotely.

The top models can ‘learn’ about your rooms and how long they take to heat, and then use that information to warm your home more efficiently.

For example, instead of programming the gadget to turn on at a particular time or temperature, you can tell some smart thermostats exactly what time you want your home to be warm.

It can then use what it has learned about how long your house takes to heat along with information from the internet about the outside temperature and brings the heating on at precisely the right time. That means no wasted energy on warmer mornings and no freezing starts if there’s suddenly a cold snap.

Some can even learn from how you use your heating, meaning they pre-empt and adjust to your preferences without being told.

Most importantly, heating more efficiently means that you don’t waste any energy, and therefore, get lower bills. And being able to track, record and measure how you use your heating can make you more mindful of how much it's going to cost, as well as highlighting where there's money to be saved.

There are a few different models on the market, each with their own take on what a smart thermostat should do. Here's a run-down of the current popular models to help you decide which is right for you...

Nest, from Google

Nest is the Google-owned 'learning thermostat'. It has a sleek, attractive design and an easy-to-navigate app. It even rewards energy-efficient decisions with a little leaf image, helping you to save money. Over time, it becomes harder to ‘earn’ a leaf, encouraging you to save even more energy.

What’s particularly smart about this thermostat is that it learns. If you turn the heating down on your way to work each day and turn it up on your return, then the Nest learns the pattern and starts doing it automatically.

Its in-built motion detector allows it to work out when the house is empty and turn the temperature down to a safe but cheap level, meaning you don’t have to re-program it when you go on holiday.

The device’s Wi-Fi capability means that you can send it commands, but it also means the gadget can access weather reports and adjust its heating accordingly. For example, it might usually begin heating a property at 6:30am to have it warm for 7am. However, if it knows there’s a frost then its algorithm might prompt it to come on a little earlier on that day to make sure it’s warm when you get up.

Its app allows you to control and program the heating, but it also gives you regular reports on your energy use, meaning you can see real-time data about how much you’re spending on heating.

Nest won’t give exact figures on estimated savings as so much depends on what customers already use and how much they change their behaviour. But it says that UK households typically save between 8.4% and 16.5% on their heating bills.

How much does a Nest thermostat cost?

Nest costs £249 with installation or £199 without, although the company recommends installation by a professional.

Hive, from British Gas

The Hive is British Gas’ smart thermostat offering.

At first glance it looks like a normal heating programmer. It has a typical LCD screen and buttons but behind the standard front is a clever gizmo that’s connected to the web and works with an app.

Again, the Hive lets you control your heating and hot water from a distance, communicating using a hub that you plug into your broadband router. It allows you to set schedules for your heating and hot water, but also to receive feedback on how much you use and energy saving tips.

British Gas says customers could save up to £150 a year by using the Hive and adapting their energy consumption as a result.

How much does a Hive thermostat cost?

The smart thermostat from British Gas costs £199 and installation takes around 90 minutes. Discounts are available for existing British Gas customers.

Connect, from Scottish Power

Scottish Power has created the Connect smart thermostat. Much like the Hive, it allows householders to adjust or program their heating and monitor their energy use through an app.

You need a good mobile phone signal in your home for this to work, and you don’t have to be a Scottish Gas customer.

That means customers can proactively manage their heating more efficiently. For example, they can tell the house to warm up on the way home or stop it coming on if they are delayed.

How much does a Connect thermostat cost?

An engineer can install Connect in your home in around 60 minutes. Prices vary depending on how much you’re willing to pay upfront – for example, Scottish Power customers can pay £80 and then £5 a month for two years, so £200 in total.

Alternatively, you can pay nothing up front but pay £12.69 a month for two years, which means a total cost of just over £304.


As with Nest, tado° is a more autonomous smart thermostat which adjusts temperatures automatically, depending on the weather. When it senses the house or flat is empty, it lowers the temperature, and raises the temperature for when you return.

It does this by pairing with an app on your smartphone that tracks your location. It also intelligently predicts the ideal temperature and monitors the weather online, meaning it can factor the temperature outdoors into its calculations. You can also manually adjust and set the heating.

According to parent company SSE, tado° can save a family with three children and a dog around £240 a year on heating bills. However, there’s an online calculator that lets you make a more accurate saving prediction based on your specific household.

How much does a tado° thermostat cost?

You can rent tado° for £5.99 a month for a minimum of 12 months, but at time of writing it’s available for £3.99 a month for the first year, rising to the standard £5.99 a month after that. Alternatively you can buy it outright for £199.

HeatSmart, from EDF Energy

This thermostat, which is available to everyone, not just EDF Energy customers, lets you control and set your heating remotely so you don’t have to heat an empty home.

It can be controlled using a smartphone, tablet or desktop. It ‘learns’ your heating habits, using what it knows about heating your home and the temperature outside to predict when the heating should come on to be most efficient.

HeatSmart also provides information on the energy you use to help you make energy-saving changes.

How much does a HeatSmart thermostat cost?

It costs £199, including the installation which takes around two hours.

The smartest move

Smart thermostats are a rapidly growing market, with new models introduced every year to make our homes smarter.

On top of the gadgets listed here you could consider the HeatMiser, Honeywell Heat Genius and others.

One thing they all have in common is that they can make a big difference to the cost of heating your home and, coupled with some changes in your behaviour, can save most households hundreds of pounds a year.

Please note: any rates or deals mentioned in this article were available at the time of writing.

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