Key takeaways
- Ofgem’s price cap rises 4% to £1,723 a year from 1 October 2026, and the gas half of the bill goes up 8%.
- The Energy Saving Trust puts the benefit of fitting proper heating controls at around £100 a year in Great Britain.
- The Hive Smart Thermostat at about £149 is the least fiddly one to live with if you just want a schedule and an app.
- If only one room is cold, a single smart radiator valve at around £56 fixes that without touching the boiler.
Ofgem confirmed on 26 August that the energy price cap goes up 4% on 1 October, taking a typical dual-fuel bill to £1,723 a year. The detail that matters for heating is buried in the notes: electricity stays roughly flat because VAT has come off it, so almost the whole rise lands on gas, which is up 8%. If you heat with a gas boiler, this is the bit of your bill that’s getting more expensive, and it’s the bit a thermostat actually controls.
That’s why smart thermostats climb the shopping lists every August. Fitting one won’t magically cut your gas use. What it does is make the boring things easy. Not heating an empty house. Not heating the spare room to living room temperature. Knocking the target down a degree without anyone noticing enough to complain about it. Here are six worth looking at, with the real catches.
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How we picked these
We started from what the Energy Saving Trust says a UK central heating system should have: a programmer for the timing, at least one room thermostat, and thermostatic radiator valves on the radiators. Anything sold as “smart” is really just those three jobs with an app bolted on, so we judged each one on how well it covers them rather than on the app’s screenshots.
Boiler compatibility decided most of it. A combi and a conventional system with a hot water cylinder need different kit, and buying the wrong box is far and away the most common mistake here. Installation mattered nearly as much, because some of these are a genuine screwdriver job and some need a Gas Safe registered engineer at the boiler. The Energy Saving Trust reckons a full professional fit of programmer, thermostat and valves runs to about £600, so a unit you can put in yourself is worth real money before you even switch it on. We also checked what sits behind a subscription, since a monthly fee quietly eats the saving.
Prices below were the Amazon.co.uk listings when we checked on 28 August 2026. They move about, so treat them as a guide. If you want to see what your heating actually costs to run before you spend anything, our heating cost index and our page on the October 2026 price cap have the current unit rates.
At a glance
| Thermostat | Best for | Boiler type | Around |
|---|---|---|---|
| Hive Smart Thermostat | Easiest to live with | Combi | £149 |
| tado° Wireless Smart Thermostat X | Cutting waste automatically | Combi or conventional | £130 |
| Google Nest Learning Thermostat (4th gen) | Setting it once and forgetting it | Combi or conventional | £210 |
| Drayton Wiser multi-zone kit | Heating rooms separately | Conventional | £180 |
| Meross Smart Thermostat for gas boilers | Spending as little as possible | Combi or conventional | £62 |
| tado° Smart Radiator Thermostat X | One cold room | Any, it’s an add-on | £56 |
The six worth a look
Hive Smart Thermostat for combi boilers
Best for easiest to live withThe one to buy if you want this over with. The dial is readable from across the room, the app is the least confusing of the lot, and it comes with the Nano 3 hub in the box so there’s nothing else to order. It’s OpenTherm compatible, which means on a modern condensing combi it can modulate the flame down rather than just switching the boiler on and off, and that’s where the efficiency actually comes from.
The catch: the receiver wires in next to the boiler, so unless you’re comfortable with that you’re paying an engineer on top. Hive also keeps adding paid tiers, and some of the cleverer scheduling sits behind Hive Heating Plus.
Combi boilers only, hub included · around £149
Check price on Amazon →tado° Wireless Smart Thermostat X starter kit
Best for cutting waste automaticallyThis is the one that does things without being asked. It notices an open window and drops the heating, and it can turn the boiler down when the last phone leaves the house and bring it back up as someone gets near. If your household leaves at unpredictable times, that’s worth more than any schedule you’d write yourself. The kit includes the Bridge X and a stand, so you can sit it on a shelf instead of drilling.
The catch: geofencing and the open window detection sit inside tado’s Auto-Assist subscription. It’s a few pounds a month, and without it you get a decent but ordinary app thermostat.
Bridge X included, hot water control · around £130
Check price on Amazon →Google Nest Learning Thermostat, 4th generation
Best for setting it once and forgetting itStill the nicest object of the six, and the only one people notice on the wall. The point of the Nest is that you nudge it for a fortnight and it builds the schedule for you, which suits anyone who was never going to sit down and programme a timer. This Pro Edition ships with a remote temperature sensor, so the boiler can respond to the bedroom rather than to a hallway that’s always colder than the rest of the house.
The catch: it’s the most expensive here by a distance, and the learning takes a couple of weeks of you overriding it before it settles. Stock on Amazon has been thin, so the price bounces around.
Temperature sensor included, works with Alexa and Google Home · around £210
Check price on Amazon →Drayton Wiser multi-zone thermostat and 2 smart radiator valve kit
Best for heating rooms separatelyMost people don’t need a warmer house, they need to stop heating three rooms nobody is in. Wiser is the cheapest sensible route to that, because the kit arrives with two smart radiator valves already in it and you can keep adding more later at a reasonable price per radiator. Each room gets its own target and its own schedule, and the hub talks to the valves over Zigbee rather than clogging your wifi.
The catch: this version is for conventional boilers with a hot water cylinder only, so check before you order. The app is functional rather than pleasant, and the Amazon reviews are the weakest of the six.
Conventional boilers, hot water control, 2 valves included · around £180
Check price on Amazon →Meross Smart Thermostat for gas boilers
Best for spending as little as possibleA third of the price of the Nest, with no hub to plug in and no subscription anywhere. It wires straight to a gas boiler and talks to Apple Home, Alexa and Google Home out of the box, which is more than some units three times the price manage. If this is a first go at smart heating, or the house is a rental you would rather not spend big on, it does the job that saves the money.
The catch: it replaces your existing wired thermostat rather than adding a wireless one, so you need mains at that spot on the wall and the confidence to isolate the circuit first. The screen looks cheap next to a Nest, and Meross support is email only.
Apple Home, Alexa and Google Home, no hub, no subscription · around £62
Check price on Amazon →tado° Smart Radiator Thermostat X
Best for one cold roomWorth saying plainly: plenty of people buying a smart thermostat have one problem room, usually a north-facing bedroom or a home office over the garage. You don’t need to touch the boiler for that. This screws onto the radiator valve in place of the plastic knob, takes about five minutes, and gives that one room a schedule of its own. Add more later if it works out.
The catch: it needs a tado° Bridge X to reach the internet, and the bridge isn’t in this box, so a first purchase means buying the starter kit instead. It also clicks audibly when it adjusts, which some people notice at night.
Fits standard radiator valves, DIY in minutes, bridge sold separately · around £56
Check price on Amazon →Questions people ask
Will a smart thermostat actually save me money
Only if it changes your behaviour. The Energy Saving Trust’s figure for fitting heating controls where there were none is about £100 a year in Great Britain. If you already have a working programmer and a thermostat you keep at a sensible temperature, the honest answer is that a smart one saves you very little, and it’s the convenience you’re buying. The saving comes from heating fewer rooms for fewer hours, not from the app.
Can I fit one myself
Radiator valves, yes. Anyone can swap a plastic TRV head for a smart one with no tools and no draining down. The wall unit is usually fine too if you’re replacing an existing wired thermostat and you know how to isolate the circuit. Anything at the boiler itself needs a Gas Safe registered engineer if it’s a gas boiler, and that’s not a rule worth bending.
Combi or conventional, and how do I tell
If you have a hot water cylinder in an airing cupboard, you have a conventional system and you need a version with hot water control. If hot water appears instantly from a single wall-mounted boiler and there’s no tank anywhere, it’s a combi. Buying the wrong one is the single most common return on these products, so check the cupboard before you check out.
Do I have to pay a subscription
Not for the basics. Every thermostat here will let you set a schedule and control it remotely for free. What sits behind a fee varies: tado° puts geofencing and open window detection in Auto-Assist, and Hive has a paid tier for some of its scheduling. Meross charges for nothing, which is part of why it’s on the list.
Is it worth buying before October
If you were going to buy anyway, yes, because the higher gas rates start on 1 October and the heating season starts around the same time. If you’re on the fence, wait. These go into Black Friday discounts most years, and the price cap sets rates for three months, so nothing is lost by fitting one in late November instead.
Sources
- Ofgem, Energy price cap will rise by 4% from October 2026, published 26 August 2026.
- Energy Saving Trust, Heating controls, last updated 10 February 2026.
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