Electric heaters in the UK

The one rule that saves the most money

Every electric heater is effectively 100% efficient — all the electricity it draws ends up as heat in your room. So the way to spend less is not to hunt for a magically efficient heater. It is to heat a smaller space for less time at a lower power. That means one room instead of the whole house, a thermostat that cuts the power once you are comfortable, and a timer so nothing runs while you sleep or leave.

The five types you will see on sale

What it costs to run

Multiply the heater's kilowatts by your unit rate. At around 27p per kWh, a 1,200 W heater costs roughly 32p an hour at full power — and considerably less in practice, because a thermostat cycles it off once the room is warm. Our running costs guide has the full table by wattage, and cheapest way to heat one room compares the alternatives.

Features worth paying for

• A real thermostat, not just high/low. Without it the heater runs flat out all evening.
• A timer. Warm the bedroom for an hour before bed rather than all night.
• Overheat protection with automatic shut-off, and a tip-over cut-off on free-standing units.
• A remote if the heater lives across the room from where you sit.
• Quiet running if it is going in a bedroom, nursery or study.

How much power does your room need?

As a rough rule, allow about 100 W per square metre for a reasonably insulated UK room, more for high ceilings, single glazing or an external door. A 9 m² bedroom is comfortable on roughly 900 W to 1,200 W. Anything over about 20 m² or open plan is a job for central heating, not a plug-in unit. Full working in the small room heater guide.

Where RapidHeat fits

RapidHeat is a portable plug-in ceramic heater built for a single room up to about 12 m². It reaches useful warmth in around five minutes, holds a temperature you set, has a timer and remote, and cuts out on overheat. It is not a whole-house solution and does not pretend to be one. If that matches how you actually get cold — one room, some of the day — it is a sensible buy. See the honest assessment or current bundle prices.