The quick answer: heating one occupied room for an hour or two may use less energy overall than heating several rooms. But electricity costs more per kWh than gas on Ofgem’s average October 2026 rates. A portable electric heater running for many hours is therefore not automatically cheaper than using gas central heating with sensible room controls.
How much does it cost to run an electric heater?
Use this calculation: heater power in kilowatts × hours used × your electricity unit rate.
On Ofgem’s average Direct Debit electricity rate of 26.32p per kWh from 1 October to 31 December 2026, the illustrative costs are:
| Heater power | One hour at full power | Four hours at full power |
|---|---|---|
| 1 kW | About 26p | About £1.05 |
| 2 kW | About 53p | About £2.11 |
These figures assume the heater draws its stated power continuously. A thermostatic heater may switch on and off once the room reaches its set temperature, so its actual use could be lower. Your regional rate or fixed tariff may also differ from the Ofgem average.
The electricity standing charge is excluded from these examples because you normally pay it whether or not you use the portable heater. If you are considering disconnecting a fuel entirely, that is a different comparison.
Is that cheaper than putting the gas central heating on?
From October, Ofgem’s average gas unit rate for a Direct Debit customer is 7.97p per kWh, compared with 26.32p per kWh for electricity. But comparing those two rates alone does not tell you which method costs less: a gas boiler heats water and may warm several rooms, while an electric heater delivers heat directly to one space.
To compare your choices, ask:
- How many rooms need to be comfortable? If several people are using different rooms, heating one room is unlikely to meet everyone’s needs.
- For how long? A short burst of local heat is a different proposition from running a portable heater throughout the day.
- What does your system do? Can you reduce heat to little-used rooms using thermostatic radiator valves, or is your heating controlled differently?
- What are your rates? Check the gas and electricity prices per kWh on your bill, especially if you have a fixed or time-of-use tariff.
For a real comparison, record your meter readings before and after similar periods of use on comparable days. Note the outdoor temperature and which rooms were heated. A single afternoon cannot prove what is cheapest all winter, but it can reveal whether a portable heater is using more electricity than you expected.
If you have a heat pump or electric storage heating: do not assume advice for a gas boiler applies to your system. Heat pumps work differently from direct electric heaters, while storage-heater costs depend heavily on when you charge them and your day and night tariff. Check your system instructions or ask an installer for advice before changing its normal schedule.
Can you heat fewer rooms without relying on a portable heater?
Often, yes. If you have gas central heating with thermostatic radiator valves, you may be able to turn down radiators in rooms you use less while keeping occupied rooms comfortable. Energy Saving Trust recommends using heating controls to heat your home when and where you need it.
Keep radiators clear of furniture, check that your timer reflects when people are actually at home, and deal with obvious draughts. If rooms remain difficult to heat, look at insulation and whether the heating system needs attention. Avoid making major changes to boiler settings unless you know what the control does and whether it affects hot water as well as radiators.
If the cost of heating is difficult to manage, check our October 2026 energy price-cap guide for an explanation of current rates. If the amount on your bill seems unexpectedly high, use our seven energy-bill checks before assuming your heating habits are entirely responsible.
The costs you should not overlook: cold rooms, damp and fire safety
Saving money matters, but so does keeping the rooms people use warm enough. UK health guidance advises trying to heat frequently used rooms, such as a living room or bedroom, to at least 18°C. This is particularly important for older people, people with reduced mobility and those with certain health conditions. Individual needs may differ, so follow medical advice where relevant.
Leaving other rooms very cold for long periods can also contribute to condensation and mould, especially where moisture and ventilation are problems. If you notice persistent damp, take it seriously rather than treating it as a necessary trade-off for a smaller bill.
Using a portable heater? Keep it well away from bedding, curtains, furniture and clothes. Do not use it to dry laundry. Place it where nobody is likely to trip over it or fall against it, and follow the manufacturer’s instructions. London Fire Brigade advises sitting at least one metre away from a heater.
A heated throw can warm a person rather than an entire room, but it does not make a dangerously cold room safe. Follow its safety instructions and check the appliance’s power rating to estimate running costs. Never use an electric blanket and hot water bottle together.
So, which is cheaper for you?
- One person, one room, a short spell: local heating may cost less overall than warming several empty rooms. Calculate the heater’s hourly cost first.
- Several occupied rooms or a whole day at home: central heating with well-used controls may be more practical and could cost less than running portable heaters for hours.
- Someone at higher risk from cold: put a safe, comfortable room temperature first and seek help with bills if cost is forcing you to leave occupied rooms too cold.
- Storage heaters or a heat pump: compare using the instructions and tariff for your particular system.
If you are struggling to afford a safe level of heating, contact your supplier about payment support and check whether you qualify for the £150 Warm Home Discount for winter 2026/27. If your energy account is substantially in credit, our energy credit refund guide</a explains how to ask for some money back while accounting for winter costs.
The MoneyMagpie verdict: heating only one room is a possible saving, not a rule. Work out the running cost of your actual heater, use the controls already in your home, and make sure the rooms people occupy remain safe and comfortable.
Sources: Ofgem October 2026 rates; Energy Saving Trust heating controls; UK government cold-weather advice; London Fire Brigade heater guidance. Checked 24 September 2026.
Disclaimer: The running costs shown are illustrations at Ofgem’s average October 2026 Direct Debit electricity rate. Your tariff, heating system, insulation, weather and usage will affect what you pay. Follow the instructions for your appliances and seek appropriate advice about health or heating-system concerns.
Great article here! Keeping the windows in your house insulated is one of the best long term ways to keep the house warmer, as less energy and heat will escape.
Lovely tips. More here – heatingoil.co.uk/news/ten-top-tips-how-slash-cost-your-heating-bills
Some great tips on here. I found that a radiator cabinet really helped in keeping our rooms warmer, we use classicradiatorcabinets.co.uk/ it also worked as a great protector to stop the children from hurting themselves.
If renovating or extending your property fitting warm water floor heating instead of radiators will cut heating bills by upto 50%, Radiators use hot water often at 70-75 degrees, floor heating uses water at 35-40 degrees….plus you get the added benefits of more comfort and more useable space. We can show you how to simple our easy to instal systems are plus we offer free estimates 01291 634149.
When starting to tackle your debt creativity is an important element. That being said don’t fool yourself into thinking paying down your debt of one card by using another one is “creative” its not! Make sure your strategies are sound and targeting your end goal… out of debt!
Does reading the units on the electricity meter and calling the service provider gain you any cashback/credit off the bill??
Go to your local Aldi or Lidl store for thermal underwear and socks at low prices
How about solar energy? Save 50% on electricity and get paid tax free index linked for 25 years for reducing the carbon footprint. Earn up to £1,560.00 pa. tax free for 25 years Government Guaranteed.
Alan
The Government is changing the Feed in Tariff from 43p to 21p on the 8th Dec 2011, so it will now take 18 years to pay back the cost of a solar PV system. Not exactly a good investment and government guarantees are not worth the paper they are printed on in this day and age.
I bought a fan for radiator from the (green site) but my husband says it does nothing at all, just money wasted.
I read your article in the daily express yesterday about fans for radiators , cant find them anywhere