The Best Smart Thermostats in the UK 2026

Choosing a smart thermostat for a UK boiler comes down to three questions. Will it talk to your boiler properly? Can it switch your hot water? And what will it cost once receivers, hubs and subscriptions are added?

For most UK homes with a gas boiler, the tado° X Wireless Smart Thermostat (2nd gen) starter kit is our top all-round pick: at £169.99 it includes a programmer with hot-water control and OpenTherm support, and its free app runs schedules even when the internet drops.

Hive's Thermostat Mini at £79 is the value alternative. Drayton Wiser suits homes that want room-by-room control.

At iHeat, our Gas Safe engineers install and service boilers from Worcester Bosch, Vaillant, Ideal, Baxi and other brands across the UK.

That means we see the practical side of controls every week: a thermostat that suits one combi can be the wrong choice for a system boiler with a cylinder.

The recommendations below compare documented features, full ownership costs and boiler fit, so you can match a model to the heating you have now or the boiler you plan to fit.

Which Smart Thermostat Should You Buy in 2026?

Our four picks cover the situations we meet most: a straightforward combi boiler, a tight budget, a household that wants the thermostat to adapt, and homes where some rooms run too hot while others stay cold.

Each choice below assumes a gas or LPG boiler controlled by a UK-specification receiver.

Best All-Round Choice for a Compatible Boiler

The tado° X Wireless Smart Thermostat (2nd gen) starter kit is the best smart thermostat for most combi boiler owners in 2026. The £169.99 kit includes a wireless receiver that works as a programmer with hot-water control and OpenTherm, so it also handles homes with a cylinder.

The wired version (£159.99) replaces an existing wired room thermostat or controls wet underfloor heating.

Its main strengths are a capable free app, schedules stored on the device and Matter support for Apple Home, Google Home and Alexa. The catch is compatibility: tado° says the X range supports a smaller set of modulating boilers than its older V3+ line.

Best Budget Choice

The Hive Thermostat Mini costs £79 with a receiver included, and it covers heating and hot water, frost protection and OpenTherm on compatible combi boilers.

You need a Hive Hub (£80) for app control, which pushes a first-time setup to around £159. If you already own a Hive Hub, the Mini is the cheapest well-featured upgrade in this list.

Best for Learning Your Routine

A learning thermostat suits households whose hours change from week to week and who would rather not keep editing schedules.

The Google Nest Learning Thermostat is the best-known example, but check that you are buying a UK model with UK support before choosing it. tado° X with its optional AI Assist subscription is the more predictable route for a UK boiler, adding pre-heating before arrival and geofencing.

Best for Room-by-Room Heating

Drayton Wiser is our pick for room-by-room heating. Its combi kit supports up to 16 rooms and 63 devices from one hub, and Wiser radiator thermostats start from £59.99 each. You can begin with the thermostat alone and add radiator valves to the rooms that give you trouble.

How Do the Leading UK Models Compare?

These systems differ most in how they talk to your boiler, whether they switch stored hot water, and what extra hardware sits between the thermostat and your router. The table summarises published specifications and prices at the time of writing.

Compare Heating and Hot-Water Features

All of these heating controls can run schedules and boost heating from an app. Hot water control is where kits split. Hive uses a single-channel receiver for combi boilers and a dual-channel receiver for systems with a cylinder; it switches hot water on, off or on boost, but water temperature stays set on the cylinder itself.

Wiser separates the two into Kit 1 (combi) and Kit 2 (heating plus stored hot water), with Kit 3 adding a second heating zone.

tado° X includes hot-water control in its wireless receiver, though the Matter integration does not currently support domestic hot water. You would switch the cylinder from the tado° app, while voice or Apple Home commands cover room heating.

Compare Hubs, Subscriptions and Smart-Home Support

tado° X needs a Bridge X (included in starter kits) or an existing Thread border router. Hive needs a Hive Hub for remote control; without one, the thermostat runs in standalone mode. Wiser builds its hub into the HubR receiver, and the hub also acts as a Matter bridge.

For energy reports and advanced automation, tado° and Hive both use paid tiers. tado° puts Energy IQ cost tracking behind AI Assist, and Hive places its Budget Tracker and Saver Mode within Hive+.

For smart home compatibility, tado° X and Wiser lean on Matter, while Hive connects directly with Alexa, Google Assistant, Apple HomeKit and Siri Shortcuts.

Is tado° X the Best All-Round Choice?

tado° X is the strongest all-rounder for a boiler it supports, combining a free app with offline schedules, Thread networking and Matter compatibility. Its limits are a narrower list of supported modulating boilers than the older V3+ range and a paid tier for the most automated features.

Wired vs. Wireless Starter Kits

The tado° Wireless Smart Thermostat X replaces a wireless room thermostat, or adds control to a boiler with no thermostat at all, and talks to a wireless receiver wired at the boiler. The wired kit swaps directly for an existing wired room thermostat. Current tado° shop prices are:

• Wireless Smart Thermostat X (2nd gen) starter kit with programmer, hot-water control and OpenTherm: £169.99

• Wired Smart Thermostat X (2nd gen) starter kit: £159.99

• Wireless Smart Thermostat X (1st gen) starter kit: £129.99 on sale

• Wired Smart Thermostat X (1st gen) starter kit: £119.99 on sale

If your home has a cylinder, the wireless kit is the one with a receiver that switches hot water. tado° designs both for DIY fitting with an app guide, though boiler-side wiring should be left to a competent installer.

What Do You Get Without AI Assist?

The free tado° app covers remote control, room schedules, boost, Quick Actions and system-specific Control Mode. AI Assist costs €3.99 a month or €29.99 a year on tado°'s published pricing and adds geofencing, pre-heating before arrival, Energy IQ reports, advanced open window detection, fault alerts and Holiday Mode.

For a household with fixed working hours, the free tier is enough. Existing Auto-Assist subscribers keep their benefits after moving to tado° X, provided they are an Admin of the new home.

Should Existing tado° V3+ Owners Upgrade?

Most tado V3+ owners with a working system have little reason to switch yet. The two ranges use different technology platforms, so they cannot share a home in the app, and the V3+ Internet Bridge will not work with X devices. Schedules and room data do not transfer automatically, which means re-entering them by hand.

There is also a compatibility risk. If your wired V3+ thermostat controls a modulating boiler that does not use OpenTherm, tado° warns that tado° X may not work with it. Upgrade when you want Matter support or you are fitting a new boiler anyway.

Which Hive Thermostat Offers Better Value?

The Hive Thermostat Mini gives the best value in the Hive range because it shares the same receivers, app and OpenTherm support as the dial model at a lower price. Hive is backed by British Gas, which offers professional installation, and Hive's own listing names specific Worcester Bosch models and control systems it cannot work with.

Hive Thermostat Mini vs. the Dial Model

Both the Mini and the dial Hive Thermostat control heating and hot water, offer frost protection, geolocation alerts and Holiday Mode, and support up to six zones on an existing multi-zone system.

The Mini is smaller (84mm square, 22mm deep) and runs on four AAA batteries; the dial model uses four AA batteries and gives you a physical dial. OpenTherm works on compatible combi boilers only, through the single-channel receiver.

Before buying any Hive Active Heating kit, check Hive's list of incompatible boilers, which includes several Worcester Bosch Greenstar HE Plus models. Honeywell SmartFit and the Vaillant VR 65 Control Centre must be removed first.

Our guide to the benefits of using a Hive thermostat for your smart home covers everyday features in more depth.

When Do You Need a Hive Hub?

You need a Hive Hub (£80) for app control, voice assistants and automations. One hub runs every Hive device in the home, so owners replacing an older Hive thermostat can reuse theirs. Without a hub, the thermostat works in standalone mode like a conventional programmable stat.

If the hub is switched off, Hive says the thermostat may lose contact with the receiver and heating stops; the receiver's heating button restores it temporarily. If issues crop up after fitting, our Hive thermostat problems guide walks through common fixes.

Is a Google Nest Thermostat Still Worth Buying in the UK?

A Google Nest thermostat is worth buying only when you can confirm it is a UK-specification model that Google still supports in the UK.

The Nest name covers several products sold in different countries, and some are built for heating and cooling systems that look nothing like a British boiler setup.

Who Benefits from a Learning Schedule?

The Nest Learning Thermostat appeals to households that want the thermostat to build its own schedule from manual adjustments. That suits irregular shift patterns or homes where nobody wants to set timers.

If your week follows a fixed pattern, a standard schedule on any model on this list does the same job. Our Google Nest thermostat guide and Hive vs Nest comparison go further into how Nest compares with Hive.

What Should Buyers Check About UK Models and Support?

Check the box and listing for UK compatibility and a Heat Link, the receiver UK Nest models use at the boiler or programmer position. Grey imports of the Google Nest Thermostat or Google Nest Thermostat E designed for other markets are a poor fit for UK wiring.

Check the exact model name, generation and Google's current UK support status before paying, and ask your installer whether features such as motion sensors or hot-water control apply to the version you are buying.

What If You Want Heating Control in Every Room?

Adding smart radiator valves turns a single thermostat into a room-by-room system, and Drayton Wiser and Honeywell Home evohome are the two leading UK platforms built around that idea. Zoned control works best in homes where rooms are used at different times, such as home offices or guest bedrooms. Our piece on the benefits of zoned heating explains the principle.

Drayton Wiser and Smart Radiator Valves

Drayton Wiser starts with a thermostat kit and expands one radiator at a time. Wiser radiator thermostats cost from £59.99, or £167.99 for a three-pack, and fit more than 95% of existing radiator valves with adapters included.

Drayton quotes more than two years of battery life on the supplied AA batteries.

Kit 1 handles combi boilers through OpenTherm or relay, Kit 2 adds stored hot water, and Kit 3 covers two heating zones plus hot water on system boilers.

Honeywell Home evohome for More Complex Layouts

Honeywell Home evohome supports up to 12 zones and handles radiators, underfloor heating and stored hot water from one controller. It works with OpenTherm boilers and heat pumps, and carries an ErP Class VIII rating for thermostat control. It is best suited to larger homes or mixed radiator and underfloor setups where multi-zone heating needs careful set-up, which is why Resideo trains installers on it.

Where Does the Honeywell Home T6 Fit?

The Honeywell Lyric T6, now sold as the Honeywell Home T6 and T6R, is a single-zone smart thermostat. It works with 24 to 230V on/off and OpenTherm appliances, including combi boilers and zone valve setups, and the T6R-HW version adds hot-water control.

It supports geofencing, Apple HomeKit, Alexa, Google Home and IFTTT, making it a sound choice for homes that want one well-integrated thermostat without radiator valves.

Will It Work with Your Boiler and Hot-Water System?

Most smart thermostats work with most gas boilers, but boiler compatibility depends on three details: whether you have a cylinder, how the boiler receives its commands, and whether the heating is split into zones. Getting these right avoids buying the wrong receiver.

Combi Boilers vs. Systems with a Hot-Water Cylinder

UK combi boilers heat water on demand, so the thermostat only needs a single heating channel. System boilers and conventional boilers heat a stored cylinder, so you need a two-channel receiver to schedule heating and hot water separately.

The Energy Saving Trust says a cylinder should also have its own thermostat. If you are weighing up a cylinder-based setup, our guide to the best system boilers is useful background.

Relay Control vs. OpenTherm Modulation

Relay control switches the boiler fully on or off. OpenTherm is a manufacturer-independent protocol that lets the thermostat ask for a lower flow temperature as the room nears its target, so the boiler runs longer at lower output.

Hive describes this as steadier room temperatures with less on/off cycling.

Support is model-specific. Hive's OpenTherm mode works on single-zone combi systems only, and tado° X supports fewer modulating boilers than V3+. Some manufacturers also offer their own weather compensation controls, such as Vaillant's sensoCOMFORT, which adjust flow temperature using outdoor readings.

When Do Zones or a Future Heat Pump Change the Choice?

Existing zone valves point towards Wiser Kit 3, evohome or a Hive multi-zone kit. Hive's OpenTherm mode does not cover multi-zone systems, so its receivers run in relay mode there.

If a heat pump is on your horizon, tado° X, Wiser and evohome all state heat pump compatibility, while Hive has not completed heat pump testing. Our thermostats for heat pumps guide covers that switch.

Which Smart Features Are Worth Paying For?

Scheduling and reliable remote control deliver most of the day-to-day value of smart heating; geofencing and voice control are useful extras once those basics are in place. Some headline features sit behind subscriptions, so check where each one lives before choosing a brand.

Geofencing, Scheduling and Voice Control

Geofencing uses your phone's GPS tracking to spot when everyone has left. Hive sends an alert to switch off, while tado° AI Assist and the Honeywell T6R adjust the temperature automatically.

Voice control through Alexa or Google Assistant is handy for quick boosts, but a good schedule does the heavy lifting.

Apple Home, Alexa and Other Integrations

For Apple Home users, tado° X connects through Matter, and Hive and the Honeywell T6R support Apple HomeKit directly. Amazon Alexa and Google Assistant work with every main platform here.

Honeywell's T6R adds IFTTT applets. Wiser and tado° X can join wider smart home integration through Matter, which Samsung SmartThings also supports; see our explainer on smart homes and smart boilers.

Which Features Need Extra Hardware or a Subscription?

• tado° X: Bridge X or Thread border router; AI Assist for geofencing, pre-heating and Energy IQ.

• Hive: Hive Hub for app and voice; Hive+ for Budget Tracker, Saver Mode, Schedule Assist and extended warranty.

• Wiser: radiator thermostats for per-room zones.

• evohome: OpenTherm bridge for modulation; radiator controllers for zones.

How Much Does a Smart Thermostat Cost to Own?

Expect to pay roughly £120 to £170 for a working single-zone setup, with room-by-room systems climbing into several hundred pounds once radiator valves are added. Subscriptions add a small yearly cost if you choose them.

Hardware, Receiver and Installation Costs

tado° starter kits include the receiver and Bridge X, so £169.99 covers the 2nd gen wireless hardware. Hive's £79 Mini includes a receiver, but a first Hive Hub adds £80.

Wiring a receiver at the boiler needs electrical competence, and Hive recommends an experienced tradesperson, so budget for fitting unless the controls are installed alongside a new boiler.

Optional Subscriptions and Expansion Costs

Hive+ costs £3.99 a month, while tado°'s AI Assist is listed at €3.99 a month or €29.99 a year. Smart radiator valves add the biggest expansion cost: six Wiser radiator thermostats at the three-pack price comes to £335.98, and tado°'s Smart Radiator Thermostat X starter kit costs £139.99.

Hive products carry a one-year warranty as standard, extended for as long as you stay a Hive+ member.

Can a Smart Thermostat Reduce Your Heating Bills?

A smart thermostat reduces heating bills when it replaces weak controls or cuts heating in empty rooms. The Energy Saving Trust estimates that installing and using heating controls effectively saves around £100 a year in Great Britain and £110 in Northern Ireland. Manufacturer claims run higher but come from their own data and modelling.

Where Better Scheduling Can Make a Difference

Savings come from heating fewer hours and fewer rooms. Schedules that match when you are home, geofencing that stops heating an empty house, and radiator valves in spare bedrooms all cut wasted gas.

Energy reports such as tado°'s Energy IQ or Hive's Heating History show where heat goes, which helps you trim schedules. Our tips on lowering your heating bill pair well with new controls.

Why Savings Depend on Your Existing Controls and Home

Homes moving from a basic timer and manual radiator valves have the most to gain. If you already use a programmer, room thermostat and TRVs carefully, the gain shrinks. Insulation, boiler efficiency and household habits all shape the result, so treat any figure as a guide.

What Should You Check Before Installation?

The most useful check before installation is your exact boiler make, model and how its existing heating controls are wired. That information decides which receiver you need and whether OpenTherm is an option.

Confirm the Exact Boiler Model and Wiring

Find the model name and GC number on the boiler's data badge and compare it against the thermostat maker's compatibility list.

Note whether you have a cylinder, zone valves or an existing wireless thermostat, and whether a manufacturer control such as Vaillant's VR 65 is fitted. A photo of the wiring centre helps an installer confirm the right kit for your combi boiler or system.

Discuss Controls When Replacing a Boiler with iHeat

A boiler replacement is the best moment to choose new controls, because the engineer can match receiver and boiler on the same visit.

Our fixed online boiler quote shows A-rated packages with warranties listed, and our in-house Gas Safe engineers check each quote. Raising your preferred thermostat with our installation team lets them confirm it suits the boiler you choose before fitting day.

Straightforward combi swaps usually take one day, and our workmanship carries a 12-month guarantee.