Heating Efficiency
The best heater settings save electricity UK households can use are usually simple: choose the lowest comfortable thermostat setting, use a timer, avoid constant full power, and heat only the rooms you actually use.
This guide focuses on the best heater settings save electricity UK readers can apply without turning the room cold or relying on product recommendations.
That does not mean making your home cold. A good setting should reduce wasted heating while keeping the room comfortable and safe. For many UK homes, this means using thermostat or eco mode instead of leaving a heater on high, setting timers around your routine, and adjusting storage heater controls before you need the heat.
There is no single perfect number for every room. A draughty living room, a small bedroom and a well-insulated home office may all need different settings. The right aim is to use the lowest setting that keeps the room warm enough without overheating it.
Best heater settings save electricity UK: quick answer
If you want a practical starting point, use this:
| Situation | Best setting approach |
|---|---|
| Room thermostat | Set the lowest comfortable temperature |
| General living space | Start around 18°C to 19°C, then raise only if needed |
| Longer use | Use thermostat, eco or timer mode |
| Quick warm-up | Use high briefly, then reduce |
| Small room or home office | Use low, medium or eco once comfortable |
| Empty room | Switch off unless there is a specific reason to keep background heat |
| Storage heater | Set input for tomorrow’s weather and output for today’s routine |
| Overnight | Only use heaters according to the manufacturer’s instructions |
Energy Saving Trust says heating controls can help keep a home comfortably warm without overheating rooms and wasting energy. It also explains that a room thermostat keeps a home at a steady temperature by turning the heating on until the chosen temperature is reached, then switching it off until the room cools slightly.
What temperature should you set an electric heater to?
If your electric heater has a thermostat, start with the lowest temperature that still feels comfortable.
For many people, a sensible starting point is around 18°C to 21°C. Energy Saving Trust recommends setting a thermostat to the lowest comfortable temperature, which it says is usually between 18°C and 21°C for most people.
- Start at 18°C or 19°C.
- Let the room warm up properly.
- Increase by 1°C only if the room still feels cold.
- Once comfortable, keep the setting steady.
Do not turn the thermostat to maximum just because it is cold outside. The room still heats towards the temperature you have selected. On colder days, it may simply take longer.
This is one of the safest ways to apply the best heater settings save electricity UK approach: reduce waste, but do not chase savings by making the room uncomfortably cold.
The NHS advises heating your home to a comfortable temperature and, if possible, keeping rooms you regularly use, such as the living room and bedroom, at least 18°C. It says this is particularly important if you have a health condition.
Is low, medium or high the cheapest heater setting?
A low setting usually uses less electricity at that moment. But the lowest setting is not automatically the best setting.
If the room never becomes comfortable, the heater may run for a long time and still do a poor job. The more useful rule is:
Use enough heat to reach comfort, then reduce the setting to maintain it.
Use high only as a short warm-up
High can make sense for a short burst when a room is cold. Once the room feels comfortable, switch to medium, low, eco or thermostat mode.
Do not leave a heater on high as the default setting. That is usually where unnecessary electricity use starts.
Use medium, eco or thermostat mode for normal comfort
For longer use, medium, eco or thermostat mode is usually more sensible than constant high power.
These modes help the heater maintain warmth rather than overshooting, switching off, letting the room cool too much, and then starting again.
Use low for small rooms or background warmth
Low can work well in a small home office, bedroom or well-insulated room. It is less useful in a large draughty space where the heater is too small.
If low does not make the room comfortable, fix the setting, the room conditions or the heating choice rather than simply leaving the heater running all day.
Should you use the timer on an electric heater?
Yes. If your heater has a timer, it is one of the most useful settings for avoiding unnecessary running time.
A timer helps you avoid heating a room when you are not using it. It can also stop the heater running for longer than planned.
- warm a room shortly before you use it
- switch the heater off automatically
- avoid heating empty rooms
- match heat to your daily routine
- reduce forgotten running time
Energy Saving Trust explains that a timer or programmer controls when heating comes on and off, making it useful for programming heating around your routine and switching it off when you are not at home or do not need heating at night.
Keep this section focused on settings. The full question of whether it is cheaper to leave heating on all day belongs in the separate article below:
leave heating on all day
Is eco mode worth using on an electric heater?
Eco mode can be useful, but it depends on the heater.
On some electric heaters, eco mode may reduce output. On others, it may use the thermostat more actively, cycle the heater on and off, or limit the target temperature. The exact behaviour depends on the model.
Use eco mode when you want to maintain comfort rather than heat the room aggressively.
Eco mode may help reduce unnecessary heating on some models, but it does not make electricity cheaper or remove the cost of long running times.
If a heater is powerful and runs for many hours, it can still use a lot of electricity. Eco mode works best when combined with a sensible thermostat setting, closed doors, good timing and realistic room expectations.
Always check the manufacturer’s manual so you know what eco mode does on your specific heater.
Best settings for heaters with a thermostat
A heater with a thermostat is easier to control than a basic on/off heater.
Instead of guessing between low, medium and high, you can set the temperature you want the room to reach. The heater then works towards that target and reduces or stops heating once the room is warm enough.
| Situation | Setting |
|---|---|
| Cold room | Set a realistic target temperature, not maximum |
| Room now comfortable | Keep the lowest comfortable setting |
| Leaving the room | Switch off or rely on timer |
| Evening use | Lower slightly if you are already warm |
| Regularly used room | Avoid dropping below a safe comfort level |
If your current heater only has basic low, medium and high settings, a thermostat heater can make temperature control easier. Use the related guide as a next step if you want to compare heaters that give you more control, but do this after you understand the settings that matter for your room.
Best heater settings by room
Different rooms need different settings. This is where the article can be more useful than a generic energy-saving guide.
Living room
For a living room, use thermostat or eco mode if available. Start low, then raise slightly only if the room still feels cold after it has had time to warm up.
- use timer for evening routines
- keep doors closed if heating one room
- avoid high power once the room is comfortable
- use thermostat mode for longer sessions
Bedroom
A bedroom should not be treated as a place to chase the lowest possible temperature.
If you need heat before bed, warm the room safely and avoid using a portable heater in a way that goes against the manufacturer’s instructions. If overnight heat is needed, use appliances and settings designed for that purpose.
- warm the room before bedtime if needed
- use timer or thermostat control
- keep the room comfortable enough
- follow the heater manual
- avoid making the room dangerously cold
The NHS recommends at least 18°C in rooms you regularly use, such as bedrooms and living rooms, if you can.
Home office
A home office is ideal for timer-based heating because it often has fixed use periods.
- heat only during working hours
- use low, medium or eco once comfortable
- switch off when leaving the room
- avoid heating the whole home if one small room is being used
Spare room
A spare room does not usually need the same comfort setting as a living room.
- heat only before use
- keep the door closed
- use background heat only if needed for damp or cold protection
- avoid full power unless someone is using the room
Bathroom
Only use heaters designed and rated for bathroom use. A normal portable heater should not be used in a wet or humid bathroom unless the manufacturer specifically confirms it is suitable.
When in doubt, do not use it there.
Best settings for electric storage heaters
Storage heaters need their own section because they work differently from portable plug-in heaters.
Energy Saving Trust says modern storage heaters often use digital controls, while older heaters usually have manual controls. Modern models usually include automatic charge control, a thermostat and a programmer or timer. Older models usually have an input dial and an output dial.
Modern storage heaters
For a modern storage heater, focus on three settings:
- Temperature
- Timer
- Setback temperature
Energy Saving Trust says digital storage heaters are easier to run once set because they can automatically store enough heat for your routine. It also says a comfortable setting is usually between 18°C and 21°C, but warns that setting the temperature too low may mean the heater does not store enough heat for the next day.
- set the temperature for comfort
- use the timer mode that matches your routine
- keep setback low enough to avoid wasting stored heat
- avoid changing settings constantly
Older manual storage heaters
Older storage heaters usually need more planning.
Use the input dial to decide how much heat to store overnight. If tomorrow will be cold, the input may need to be higher. If tomorrow will be mild, a lower input can help avoid storing heat you do not need.
Use the output dial to control how quickly the stored heat is released. Energy Saving Trust recommends leaving the output dial on the minimum setting if you are out during the day, so the heat lasts longer.
Boost mode
Use boost only when you really need it.
Energy Saving Trust says boost should only be used if you have run out of stored heat, and that it may use the most expensive electricity rate if you are on an Economy 7 tariff.
Plan input and output first. Use boost as a backup, not as your everyday setting.
Common heater setting mistakes that waste electricity
Leaving the heater on high after the room is warm
High is for a short warm-up, not for maintaining comfort all evening.
Ignoring the timer
Without a timer, it is easy to leave a heater running longer than intended.
Heating empty rooms
If nobody is using the room, the heater is usually doing work that does not benefit anyone.
Using boost too often
On storage heaters, boost should be treated as a backup, not the normal setting.
Blocking the thermostat or airflow
If the thermostat sensor is blocked or the heater is covered, the appliance may not read the room temperature properly. Always follow the manufacturer’s instructions.
Trying to fix heat loss with settings alone
If a room loses heat quickly, heater settings can only do so much. Draughts, open doors and poor insulation can make the heater run longer.
For the wider energy-saving strategy, use this future link slot only when the destination is live:
reduce electric heating costs
When heater settings will not save much electricity
Settings help most when the heater is already suitable for the room.
They may not help much if:
- the room is very draughty
- the heater is too small
- the room is used all day as the main heat source
- the thermostat is inaccurate
- the heater is badly positioned
- the property loses heat quickly
- boost mode is used too often
In these cases, the next step is not to keep lowering the setting. It may be better to calculate the running cost, improve heat retention, or use a heater with better controls.
Keep the calculator link inactive until the calculator page is live:
electric heater running cost calculator uk
Final recommendation
The best heater settings save electricity UK households can use are not extreme settings. They are controlled settings.
- the lowest comfortable thermostat setting
- a timer based on your routine
- eco mode for maintaining warmth, if your model supports it
- high power only for short warm-up periods
- low or medium once the room is comfortable
- storage heater input based on tomorrow’s weather
- storage heater output based on today’s routine
- boost only when needed
The aim is not to be cold. The aim is to stop paying for heat that does not improve comfort.
For most homes, the best heater setting is the lowest setting that keeps the room comfortable, safe and controlled.
FAQs
What is the best heater setting to save electricity?
The best setting is usually the lowest comfortable thermostat setting, combined with a timer or eco mode. For many people, around 18°C to 21°C is a sensible starting range, but the right setting depends on the room, the person and the property.
Is low heat cheaper than high heat?
Low heat usually uses less electricity at that moment, but it may not heat the room properly. A better approach is to use enough heat to reach comfort, then reduce the setting or use thermostat mode.
Is eco mode cheaper on an electric heater?
Eco mode can help reduce unnecessary heating on some models, but it depends on the heater. It may reduce output, limit the target temperature or cycle the heater more actively. Check the manufacturer’s manual for what eco mode actually does on your model.
Should I leave an electric heater on overnight?
Only use a heater overnight if it is designed for that use and the manufacturer’s instructions allow it. For portable heaters, follow the manual carefully and avoid unattended use that creates safety risk.
What is the best storage heater setting?
For modern storage heaters, set a comfortable temperature, use the timer and avoid setting setback too high. For older storage heaters, set the input based on how cold tomorrow is likely to be and keep the output low when heat is not needed.
Why does my heater still use a lot of electricity?
The room may be losing heat quickly, the heater may be too small, or the heater may be running for too many hours. Settings help, but they cannot fully fix draughts, poor insulation or the wrong heater size.
Can a thermostat heater save electricity?
A thermostat heater can help avoid overheating by reducing or stopping heat once the room reaches the target temperature. It does not make electricity cheaper, but it can make the heater easier to control.