We buy all the electric heaters we test. We put the bestselling heaters from popular UK retailers through these tests: Heating speed, evenness, and accuracy Convector heaters are usually taller than fan heaters, but thin and light – making them larger, but still relatively easy to move between rooms.

Under current energy prices, a run-of-the-mill plug-in electric heater can cost approximately 40p to 65p per hour to run on full blast. We assess how easily each electric heater can be set up and how easily understandable the controls and settings are. We used any handles to lift the heater and move it around. While some heaters can be used straight out of the box, others have complicated program and timer settings.The Dragon 4 radiator is ideal for rooms up to75m³. It has a 2.5kW heat output and 3 heat settings, making it easier for you to find the ideal temperature With an enlarged fin shape, it delivers an increased chimney (convective) effect for faster hot air flow. Portable electric heaters use electricity, which costs 27.35p/kWh under the current energy price cap. Depending on how effective the heater is, they can take anything from 30 minutes to an hour to notably raise the temperature of a medium-sized room, so if you're only planning on using it until the room gets up to temperature, it will likely cost you between 28 and 55p.

We set up each heater in the centre of our test room and run it on the maximum settings, with the room starting at a cool temperature. We monitor how much the room temperature changed over the course of an hour using temperature probes. We found the most drastic changes happen in the first half an hour and increases in temperature become more incremental after that.These can still be bought, but they aren't as popular or widely available as fan or convector heaters. If you were to try replacing the use of your central heating by putting an electric heater in each room, it will definitely end up costing much more. These have exposed heating elements, which heat up cold air as it passes. This often leads to slower, but more even, heating. They tend to be a little slower than fan heaters, but are quieter, and our tests found some are still pretty speedy. BTU stands for British Thermal Units and represents the level of heat a radiator provides. The required BTU level to heat your room will influence the size of your radiators. Fortunately, we offer numerous options in all shapes, styles and sizes for you to find one that's right for you. How is it calculated? Pinning down an exact comparison of how much central heating and electric heaters cost to run is nigh-on impossible, as the factors below are just some of the variables that play a part:

In our tests, we set every heater to run at full blast so you can see the maximum amount it cost to heat our medium-sized test room. If you have the thermostat of your heater set to a desired temperature, the heater will toggle on and off once it reaches that temperature – depending on what's needed to maintain it. The heater won't operate continuously, so won't cost you as much to run. Are electric heaters cheaper to use than central heating? Adjustable thermostat Using this function, a portable heater will heat the room and when the desired temperature is reached, it will try to maintain the room at that temperature. Most of the cheaper, simpler heaters we tested have a dial thermostat that doesn't let you choose specific temperatures in °C. You'll likely need to buy a more expensive model for that. Our tests also found that they're rarely 100% accurate and will probably think the room is a couple of °C warmer or cooler than it is. We use a force meter to record how much is needed to topple each heater over and a decibel meter to measure how much noise each one makes while running.Although the comparison might make your electric heater look cheaper to run, bear in mind that it will only be heating a much smaller area, whereas your central heating will be aiming to heat your whole home. Programmable timer Useful for setting a heater to turn on just before you get home or wake up, so there's no waiting around for the heater to warm up. On the downside, this type can be quite noisy and they don't have some of the more advanced features you can get with convector heaters.

Central heating is much more effective at maintaining a stable temperature over a longer period, whereas the heat from an electric heater will soon dissipate if the rest of your home is cold. Read our full story on illegal and dangerous plug-in mini heaters for sale on online marketplaces to see those we identified as having serious safety risks. New enlarged battery design. The 25% larger radiant surface ensures faster air flow emission and increased chimney effect Frost protection The heater can be set to heat automatically when the temperature drops below 5°C, but you'll need to have it on standby for it to run, so this can limit its usefulness.Some portable heaters have useful extras, such as an LCD screen that displays the current temperature or a remote control for turning the heater on from across the room. These features may come in handy: Some modern options also have smart features so you can program them via companion apps and smart speakers. The oil in the radiator acts as a heat reservoir, which stays hot for some time after the heater's switched off. Some are called 'oil-free' and function in a comparable way, just with an internal heating element instead of any oil. Due to the long list of factors that come into play to calculate your central heating costs, the only way you can confidently compare a heater to your central heating is to install a smart meter. You then divide your weekly heating cost by the number of hours you have it switched on and compare that figure to the cost of running your heater.