Hearth & Lawn

The cheapest heater to run in the UK

Last updated: · By the Hearth & Lawn team

How we chose these: We haven't tested these heaters ourselves. Our picks are based on manufacturer specifications, UK retailer and price-comparison listings, independent reviews (Which?, Ideal Home) and patterns in owner reviews. Running costs are our own calculations from the rated power. Prices were checked on 18 October 2026.

Here's the thing most "cheapest heater" adverts leave out: every plug-in electric heater turns electricity into heat at essentially the same rate. A 2kW oil-filled radiator, a 2kW fan heater and a 2kW convector all give out about 2kW of heat and cost the same per hour at full power: about 53p at the current price cap.

So the cheapest heater is the one that uses the fewest watts for the fewest hours while keeping you comfortable. That usually means:

  1. Heat yourself, not the room, with a heated throw or electric blanket: about 1.6–4p an hour.
  2. Heat one small room with a thermostat and timer, and keep the door shut.
  3. Use the right type for how long you need heat: a fan heater for a quick 20-minute blast, an oil-filled radiator for a whole evening.

Running costs compared

At the Ofgem price cap of 26.32p per kWh (average direct debit electricity, 1 October to 31 December 2026):

Heater Typical power Sum Cost per hour at full power
Electric blanket (one side of a double) 60W 0.06 × 26.32 1.6p
Heated throw 100–150W 0.1–0.15 × 26.32 2.6–3.9p
Oil-free radiator on low (Dimplex ECR20TIE) 600W 0.6 × 26.32 15.8p
Oil-filled radiator on low (De'Longhi Dragon 4) 900W 0.9 × 26.32 23.7p
Fan heater or oil-filled radiator, full power 2,000W 2 × 26.32 52.6p
Large oil-filled radiator (Pro Breeze 11-fin) 2,500W 2.5 × 26.32 65.8p

These are full-power figures. Once the room reaches the temperature you've set, the thermostat switches the element on and off. For example, if it ends up heating half the time, a 2kW heater averages about 26p an hour. That share depends on the room, the insulation and how cold it is outside, so we can't give you a single real-world figure.

Work out your own figures with our running-cost calculator

You can also try the calculator presets for a fan heater and an electric blanket.

Is a plug-in heater cheaper than gas central heating?

Usually not, per unit of heat. Ofgem's cap for gas is 7.97p per kWh (1 October to 31 December 2026), against 26.32p for electricity. A modern gas boiler turns most of that gas into heat, so heat from gas costs very roughly a third of heat from a plug-in electric heater.

A plug-in heater only saves money when it lets you leave the central heating off and heat one small room instead of the whole house, for example if you live alone or work from home in a box room. If you have central heating, first try turning the radiator valves down in rooms you aren't using.

Which type of heater?

Oil-filled radiators: best for long spells in one room

An electric element heats oil sealed inside the fins, and the fins give off steady, quiet heat. Electrical Safety First says they take longer to warm up but keep giving out heat after they switch off, and that they are generally more economical to run. That isn't because they turn electricity into heat more efficiently. The stored heat evens out the warmth as the thermostat switches on and off, which can make a lower setting feel comfortable. They're the best choice for an evening in the living room or warming a bedroom before bed. They're heavy, and the fins stay hot for a while.

Oil-free (dry) column radiators: lighter and quicker

These look like oil-filled radiators but use a solid element. They're lighter and warm up faster, but hold less heat after switching off.

Fan heaters: cheapest to buy, best for short bursts

They blow hot air and warm a small space in minutes, which suits a quick warm-up of a bathroom or study. They're noisy, and the heat disappears as soon as they stop. Electrical Safety First warns the hot air can be intense, so keep them clear of curtains, bedding, furniture and people, and keep the vents free of dust.

Infrared panels and halogen heaters: heat you, not the air

Infrared heaters warm the people and objects in front of them, a bit like the sun. You can feel warm quickly without heating all the air, which can help in draughty rooms or if you sit in one spot. But a 600W infrared panel still costs exactly 0.6 × 26.32 = 15.8p an hour. Be wary of claims of dramatic savings. Halogen heaters must be kept well away from anything flammable.

Heated throws and electric blankets: by far the cheapest warmth

At 60–150W, these use a small fraction of a room heater's power. See our best electric blankets and heated throws, with costs per hour and the safety checks to do before winter.

Heater safety: read this first

London Fire Brigade says fires involving heaters have a particularly high fatality rate. It says electric heaters cause over 160 fires a year, and that a third of electrical fires that ended in a death involved heaters. Electrical Safety First and London Fire Brigade advise:

  • Buy new, from a reputable retailer, with a UK 3-pin plug. Avoid second-hand heaters and unknown third-party sellers.
  • Choose one with a tip-over switch and overheat cut-out. All three of our picks have both.
  • Keep it at least one metre from curtains, bedding, furniture, paper and clothes, and sit at least a metre away.
  • Never dry clothes on or near a heater. Use a heated airer instead.
  • Plug it straight into a wall socket, not an extension lead or adaptor, which can easily be overloaded.
  • Don't leave it on unattended or while you sleep. Electrical Safety First recommends against overnight use. If you do run one overnight, it suggests an oil-filled radiator as the lower-risk type, with everything a metre clear and smoke alarms fitted.
  • Fit smoke alarms (at least one per floor) and test them monthly.
  • Register your heater with the maker so you hear about recalls.
  • Take extra care if anyone in the home has mobility problems. London Fire Brigade warns they're at particular risk of falling onto a heater.

The best heaters in detail

1. De'Longhi Dragon 4 TRD40820T (2kW): best oil-filled radiator

Price checked: from £148.75 on idealo UK (18 October 2026); De'Longhi lists it at £174.99 but showed it out of stock. Other retailers ranged up to about £222.

Key specs (De'Longhi, idealo):

  • Oil-filled; three settings: 900W, 1,100W and 2,000W
  • Thermostat; mechanical 24-hour timer; anti-frost setting
  • 8 fins with De'Longhi's "chimney" design
  • 44 × 16 × 65cm; 14.1kg; pre-assembled folding castors
  • For rooms up to 60m³; IP24 splash protection (per idealo's listing)
  • 2-year warranty from De'Longhi's shop

The Dragon 4 is the oil-filled radiator reviewers recommend most often. It's built to hold its heat and keep releasing it after switching off. The 900W setting suits a small room once it's warm, at about 24p an hour flat out.

Ideal Home's tester, using the bigger 2.5kW version, found the timer's push-in segments fiddly. At 14kg it's heavy to carry upstairs.

Pros

  • Steady, quiet heat that lingers
  • Useful low setting
  • Timer and frost setting
  • Reputable brand

Cons

  • Expensive for a portable heater
  • Heavy
  • Fiddly mechanical timer

2. Dimplex ECR20TIE (2kW oil-free): best value, quickest warm-up

Price checked: £89.99 at Dimplex's shop (RRP £112.99); about £76 on Amazon according to a price tracker on 18 October 2026.

Key specs (Dimplex):

  • Oil-free "Thermocore" element; three settings: 600W, 1.4kW and 2kW
  • Thermostat, frost protection, electronic timer
  • Tilt switch and overheat cut-out
  • 10.8kg; 1.8m cable; castors (Dimplex's page lists two slightly different sets of dimensions, about 63–65cm tall)

This is a lighter, cheaper alternative to an oil-filled radiator, with a lower 600W setting (about 16p an hour). Dimplex claims it warms up up to 30% faster and uses up to 9% less energy than a 2kW oil-filled column, but that's from Dimplex's own test, not an independent one. Without oil, it won't keep giving out heat for long once it switches off.

Note: Dimplex's own product page describes the timer as both "24-hour programmable" and "7-day programmable". Check the manual if a weekly schedule matters to you.

Pros

  • Cheaper and lighter than oil-filled models
  • Low 600W setting
  • Programmable electronic timer

Cons

  • Less retained heat
  • Conflicting timer details on the maker's page

3. Pro Breeze 2500W Oil-Filled Radiator, 11 fins (PB-H-02): best for bigger rooms on a budget

Price checked: £89.99 at Pro Breeze (black); the white version was about £79.99 on Amazon UK (seen via search, 18 October 2026).

Key specs (Pro Breeze):

  • Oil-filled; 2,500W maximum; three heat settings
  • Adjustable thermostat; 24-hour timer
  • Tip-over switch and overheat protection
  • 50 × 24 × 62cm; 10.85kg; 1.5m cable; wheels
  • Suggested room size up to 30m²

For a large or draughty living room, the extra 500W helps it warm up faster. Remember that the full 2.5kW costs about 66p an hour, so use the thermostat and a lower setting once the room is warm. Pro Breeze says it heats a room 30% faster than "a competitor 2500W fan heater"; that's the maker's own comparison.

Pros

  • Most power for the money
  • Lighter than the De'Longhi
  • Timer and thermostat

Cons

  • Highest cost per hour at full power
  • Lesser-known brand than De'Longhi or Dimplex

Want a fan heater instead? For short bursts, any fan heater from a reputable brand and retailer with a thermostat, tip-over switch and overheat cut-out will do the job. The cost per hour is the same as any other heater of the same wattage, so choose by features and safety, not by "low-energy" claims.

See also: cheap draught-proofing fixes and smart thermostats compared.

FAQs

What is the cheapest electric heater to run? Per kWh, they all cost the same, because they all turn electricity into heat. The cheapest in practice is the lowest-wattage option that keeps you warm. A heated throw (about 3p an hour) beats any room heater, and a heater with a thermostat and low setting beats one without.

Are oil-filled radiators cheaper to run than fan heaters? Not per hour at the same wattage: 2kW is 52.6p an hour either way. Oil-filled radiators hold their heat after the thermostat cuts out and give steadier warmth, which suits long spells. Fan heaters suit quick bursts.

How much does a 2kW heater cost per hour? 2kW × 26.32p = 52.6p an hour at full power, at the 1 October to 31 December 2026 price cap. Less once the thermostat starts cycling.

Is it cheaper to heat one room with an electric heater than to put the central heating on? Only if it means the central heating stays off. Heat from gas costs roughly a third as much per kWh, so heating the whole house with gas can still be cheaper than you'd think. Turning down radiator valves in empty rooms is often the better first step.

Can I leave an oil-filled radiator on overnight? Electrical Safety First recommends not running any portable heater overnight. If you must, it suggests an oil-filled radiator as the lower-risk choice, with everything kept a metre away and working smoke alarms. Warming the room before bed and switching off is safer.

Do infrared heaters save money? They can feel efficient because they warm you directly, but they cost exactly the same per kWh as any other electric heater. Compare them on wattage and how long you'd run them.

Sources