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 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. Cold air setting Some fan heaters can help cool you down too. They're not nearly as effective as a dedicated air conditioner, but a light breeze of cold air is better than nothing. 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. These can still be bought, but they aren't as popular or widely available as fan or convector heaters.

Convector heaters are usually taller than fan heaters, but thin and light – making them larger, but still relatively easy to move between rooms.For such a small and keenly priced unit, the Russell Hobbs comes with a variable temperature thermostat and two heat settings – 750W and 1,500W. Granted, the thermostat control is a simple dial, so it isn’t possible to set an actual room temperature, but that’s par for the course with a heater at this price. 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. 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. This model comes with a basic remote control that allows you to adjust oscillation, power settings and room temperature and set an eight-hour timer. You can also control its most basic settings using the large digital display. The VonHaus comes with two power outputs (1kW and 2kW), a single fan speed and a digitally controlled room temperature thermostat for accurate operation.

Build quality is excellent, it looks attractive and its compact size (it’s just 28.5cm wide and 16cm in height) means it won’t get in the way. It’s just the job for heating up a space without fuss. There’s no doubt the Dyson Hot+Cool is expensive, but for your spend you’re getting the best of three worlds: heating in the winter, cooling in the summer and arguably the best air filtration system in the business. 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. 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.If you can afford it, the Dyson Purifier Hot+Cool Formaldehyde is a sterling choice for winter warmth and air purification. What’s more, when the summer months arrive, you can turn off the heater element and enjoy a cooling breeze instead. 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. Using Dyson’s unique Air Multiplier technology combined with variable oscillation up to an impressive 350 degrees, the Hot+Cool delivers a good wallop of warmth. According to the company, this heater will provide full coverage in rooms up to 81m³. As well as a built-in thermostat, air flow can be altered using the included magnetic remote control or, if you prefer, via Dyson’s excellent app. 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. 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.