Room size
More volume to heat means more energy used, whatever the radiator. Ceiling height counts as much as floor area.
Running costs
What actually decides how much your electric radiators cost to run
There’s no single number that applies to every home. But there is a straightforward answer, and a few things worth knowing before you believe a “1p an hour” headline.
Or call us on 01209 714600.
- Room size
- Insulation
- How you use it
- Your tariff
The honest answer
Four things decide your running cost, not the radiator alone
Two identical radiators can cost very different amounts to run, because the radiator itself is only one part of the equation.
Insulation
A well-insulated room holds its heat, so the radiator needs to top it up less often.
How you use it
Heating a room all evening costs more than heating it for an hour. Rooms you don’t heat cost nothing.
Your tariff
Standard rate, Economy 7 or a smart tariff all price the same unit of electricity differently.
This is why we don’t quote a single running-cost figure on this page, and why our free survey looks at your actual rooms, not a generic average. Book a free survey
A straight answer
Is it true electric heaters can run for 1p an hour?
The claim
“Runs for as little as 1p per hour”
You’ll see claims like this from some electric heating brands, and they’re not made up. But they don’t tell you the conditions behind the number.
The reality
Figures like this are usually true only for a low-wattage heater, run briefly, on a cheap-rate tariff, in a small or well-insulated space. For a whole home, heated for a normal evening on a standard tariff, the real figure is higher. We’d rather tell you that now than let you find out later.
What we can say honestly: room-by-room control means you never pay to heat rooms you’re not using, and that’s the biggest lever on your bill, more than any per-hour figure.
What you can control
The biggest saving isn’t the radiator, it’s how you use it
Every radTherm radiator has a digital thermostat that holds your set temperature precisely, so it isn’t switching on and off wastefully. Add room-by-room control, from the radiator or the app, and you stop paying to heat rooms nobody’s in.
That’s the most common source of wasted spend we see when people switch from whole-house systems like storage heaters or old gas central heating.
Common questions
Running costs: what people ask us
The questions we’re asked most often by people working out what electric heating will cost them.
How much does it cost to run a radTherm electric radiator?
It depends on room size, insulation, how you use it and your tariff, so there’s no single figure that’s accurate for every home. What we can say is that room-by-room control means you only pay for the heat you use, rather than heating your whole home on a fixed schedule. Our free survey gives you a running-cost estimate based on your own rooms, not a generic average.
Is it true electric heaters can run for 1p an hour?
Sometimes, under specific conditions: a low-wattage heater, run briefly, on a cheap tariff, in a small or well-insulated room. It isn’t a realistic figure for heating a whole home through a normal evening on a standard tariff.
What decides how much my electric radiators cost to run?
Four things: room size and ceiling height, how well insulated the room is, how you use the radiator (constant background heat or only when needed), and your electricity tariff. The radiator itself matters less than these four.
Can I reduce my running costs with the app or thermostat?
Yes. The biggest lever on your bill is not heating rooms you’re not using. Room-by-room control, from the radiator’s own thermostat or the app, stops you paying for background heat in empty rooms.
Do I have to stay on Economy 7?
No. radTherm radiators work on a standard tariff, so you’re not tied to Economy 7’s daytime rates. If you’re switching from storage heaters, our storage heater running costs guide has the full tariff comparison.
Is there a running cost calculator?
Not an online one yet. A genuinely accurate figure depends on your rooms, insulation and usage, and a generic calculator would just produce another number that doesn’t apply to your home. The free survey does that job instead: Neil measures your rooms and gives you a running-cost estimate for your home.
Keep reading
More about our radiators
Storage heater running costs
The full tariff comparison if you’re replacing storage heaters.
Compare with storage heatersElectric vs gas
An honest look at the total cost of each, boiler included.
Compare with gasHow they work
Why a radTherm radiator only needs power for part of each hour.
How it worksSee the full range
Get an estimate for your home
The brochure covers every radTherm size, with honest comparisons against gas, oil and storage heating. Prices and running-cost estimates come from us, not the brochure: book a free survey for a room-by-room estimate for your home.