The 10 Best Oil-Filled Radiators of 2026, Ranked

Every kilowatt of heat costs the same whatever heater makes it, so a 2500W radiator at full power uses 2.5kWh an hour. At about 25p to 30p a unit that is roughly 63p to 75p an hour. Once the room reaches the thermostat setting the element cycles on and off, so the average cost over an hour is often well below that. A timer and thermostat are what keep the bill down.

Roughly 1000W to 1500W suits a small room such as a box room or bedroom, and 2000W to 2500W suits a large living room or a conservatory. Most radiators have three settings, such as 1000W, 1500W and 2500W. Use the highest to warm the room, then drop to a lower one to hold the temperature. Poor insulation and single glazing push you towards the bigger models.

An oil-filled radiator warms up more slowly but keeps giving off heat for a while after it switches off, which suits a room used for hours at a time. A convector heats the air faster and is lighter, but cools quickly once it stops. Both run silently, apart from the odd click from an oil-filled radiator as it heats and cools.

An oil-filled radiator is usually the better bedroom choice. It is silent apart from occasional clicks, does not blow dust about and holds its warmth through the night. A fan heater warms a small space faster but is noisy and stops heating the moment you switch it off.

The oil is sealed in for the life of the heater and never needs topping up, and there are few moving parts. Many last ten years or more, and several makers give a two-year warranty. The parts that fail are usually the thermostat dial, the timer or the plug lead.

Models with a tip-over switch and an overheat cut-off are designed to be left running, and the fins stay cooler than a bar fire. The surface still gets hot, so keep it clear of bedding and curtains and plug it directly into a wall socket, not an extension lead. Do not dry clothes on it unless the maker says you can. A child lock helps if there are young children in the house.