How Much Does It Cost to Run a Dehumidifier in the UK?

These figures are estimates based on continuous power draw. Actual costs will vary depending on how long the compressor runs, room conditions, humidity settings and your electricity tariff.

What Affects Dehumidifier Running Costs?

Several factors can affect how much electricity your dehumidifier uses.

Dehumidifier Power Rating

A higher-wattage dehumidifier generally consumes more electricity while operating. However, choosing a larger and more efficient unit for a large or particularly damp room can sometimes reduce total operating time.

Operating Hours

The longer a dehumidifier runs, the more electricity it can consume. Running a unit for 12 hours a day will generally use more electricity than running it for 4 hours.

However, many modern dehumidifiers have humidity sensors and automatic modes that allow them to stop or reduce operation once the target humidity is reached.

Room Humidity

A very humid room requires more moisture removal. If humidity levels are consistently high, the dehumidifier may need to run for longer periods.

Activities such as showering, cooking, drying clothes indoors, and poor ventilation can also introduce additional moisture into the air.

Room Size

Using an undersized dehumidifier in a large room can cause it to run for longer periods. Selecting a unit with an appropriate capacity for the space can help it reach the desired humidity level more efficiently.

Temperature

Temperature can affect how effectively a dehumidifier operates. Compressor-based dehumidifiers generally work most efficiently in warmer conditions. In colder spaces, their performance may decline and they may require more frequent defrosting.

Target Humidity

Setting an extremely low humidity level can increase operating time.

A more recent UK local-authority source, Epping Forest District Council, says that 30%–60% is a good indoor humidity range for comfort and health, while humidity below about 30% can cause dryness.

Electricity Rates

Your electricity tariff has a direct impact on running costs. Two households using exactly the same dehumidifier for the same amount of time can pay different amounts if their electricity rates differ.

How to Reduce Dehumidifier Running Costs?

You don't necessarily need to stop using a dehumidifier to reduce your electricity bill. A few simple changes can help lower its energy consumption.

Appropriate Humidity Level

Avoid setting the humidity target unnecessarily low. Many modern dehumidifiers display the room’s current relative humidity, helping you choose an appropriate target. Once the target is reached, the unit can cycle off to reduce unnecessary operation.

Close Doors and Windows

When using a dehumidifier in a particular room, keeping doors and windows closed can help prevent humid outdoor air from continuously entering the space.

Use the Right Size

Choose a dehumidifier designed for the size and moisture level of the room. An undersized unit may need to operate for much longer to achieve the same result.

Clean the Filter

A dirty air filter can restrict airflow and affect performance. Follow the manufacturer's instructions for cleaning or replacing the filter.

Reduce Moisture at the Source

Reducing the amount of moisture entering your home can reduce the workload on your dehumidifier. Using extractor fans while cooking or showering and improving ventilation where appropriate can help.

Use a Timer or Smart Mode

If your dehumidifier has a timer, humidistat, or automatic mode, use these functions to prevent unnecessary operation when the room is already dry enough.

Consider Using Solar or Battery Power

If your home has solar panels, battery storage can save surplus solar energy for running a dehumidifier later in the day. Depending on your tariff, it can also store lower-cost off-peak electricity for later use, helping reduce reliance on grid power at more expensive times.

For example, the BLUETTI Apex 300 battery backup has a base capacity of 2,764.8Wh and supports solar charging. A 300W dehumidifier would have a theoretical runtime of about 9.2 hours based on rated capacity (2,764.8Wh ÷ 300W). Actual runtime will vary with inverter losses and the dehumidifier’s real power consumption.

Any cost savings will depend on how the battery is charged and your electricity tariff.

Are Dehumidifiers Expensive to Run?

Dehumidifiers are generally not expensive to run compared with many higher-power household appliances, although the total cost depends on the unit's wattage, how long it operates and your electricity tariff. At an electricity rate of 26.32p/kWh, the household compressor dehumidifiers used in the examples above would cost around 4p to 7p per hour when running continuously.

For example, a 216W dehumidifier would cost about 6p per hour, or approximately 45p if it ran continuously for eight hours. In practice, the actual cost may be lower because a humidistat can switch the compressor off once the target humidity level is reached.

Running costs can become more noticeable if the dehumidifier operates for long periods every day, has a higher power rating, or is used in conditions that require it to work for longer. The most accurate way to estimate your own cost is to use the appliance's rated wattage, actual operating time and the electricity unit rate on your tariff.

Is It Cheaper to Use a Dehumidifier Than a Tumble Dryer?

Using a dehumidifier with a drying rack can be cheaper than using a traditional vented or condenser tumble dryer, but the comparison depends on the type of dryer, the dehumidifier's power consumption and how long the clothes take to dry. Modern heat pump tumble dryers can be much more energy-efficient, so the cost difference may be smaller.

A dehumidifier typically uses much less power while it is running, but it also takes longer to dry clothes. This means power rating alone does not tell you which option is cheaper. The more useful comparison is the total electricity used for a complete drying session.

A 216W dehumidifier running continuously for six hours would use:

0.216kW × 6 hours = 1.296kWh

At 26.32p/kWh, this would cost approximately:

1.296kWh × £0.2632 = £0.34

The cost of a tumble dryer should be compared on the same basis: the electricity consumed during one complete drying cycle × your electricity unit rate. Vented, condenser and heat pump dryers can have very different energy consumption, so there is no single tumble-dryer cost that applies to every model.

A tumble dryer is generally faster, while drying clothes on an airer with a dehumidifier takes longer. If you use a dehumidifier, placing the airer in an enclosed room, keeping doors and windows closed, and using a laundry or humidistat mode where available can help the unit remove moisture more effectively.

Conclusion

A dehumidifier does use electricity, but for most household models, the running cost is relatively modest when compared with many high-power appliances. Based on the examples in this guide, a typical 150–270W dehumidifier costs around 4p to 7p per hour at an electricity rate of 26.32p/kWh. A 216W model, for example, would use around 1.73kWh and cost approximately 45p over eight hours if it operated continuously.

In practice, your actual electricity use and running costs may be lower because many dehumidifiers use a humidistat to switch the compressor on and off as needed. Room temperature, humidity, target humidity, room size, operating time and your electricity tariff can all affect how much energy the appliance consumes.

To keep running costs under control, choose a suitably sized model, avoid setting the humidity unnecessarily low, keep doors and windows closed while the unit is operating, clean the filter regularly, and use automatic or humidistat modes where available. If you have solar panels or battery storage, you can also use surplus or lower-cost electricity to power the dehumidifier.

Ultimately, the best way to estimate your own cost is simple: multiply your dehumidifier's power consumption by its actual operating time and your electricity unit rate. This gives you a more realistic estimate than relying on the appliance's wattage alone.

FAQs About Dehumidifier Running Costs

How Much Does It Cost to Run a Dehumidifier for 24 Hours?

At an electricity rate of 26.32p/kWh, running a household compressor dehumidifier rated at around 150–250W continuously for 24 hours would cost approximately £0.95 to £1.58.

For example, a 216W dehumidifier running continuously for 24 hours would consume:

0.216kW × 24 hours = 5.184kWh

At 26.32p/kWh (£0.2632/kWh):

5.184kWh × £0.2632 = £1.36

So, a 216W dehumidifier would cost approximately £1.36 to run continuously for 24 hours. This is a theoretical maximum based on continuous operation at the rated power. Actual costs may be lower if the humidistat cycles the compressor off after the target humidity is reached.

How Many Hours a Day Should You Run a Dehumidifier?

There is no fixed number of hours a dehumidifier should run each day. Runtime depends on indoor humidity, room size, moisture levels, and the dehumidifier's capacity. In damp conditions, it may need to run for several hours, while drier rooms may require less use. If available, use the humidistat to maintain your target humidity rather than relying on a fixed daily runtime.

Is a Heater or Dehumidifier More Expensive to Run?

It depends on the power rating and how long each appliance operates.

For example, a 2,000W heater uses:

2.0kW × 1 hour = 2kWh

A 300W dehumidifier uses:

0.3kW × 1 hour = 0.3kWh

Therefore, the heater consumes considerably more electricity per hour in this example. However, comparing appliances solely by wattage does not tell the whole story. They perform different jobs, and the amount of time each appliance needs to achieve its purpose can be very different.

Is It Cheaper to Run a Dehumidifier or an AC Unit?

It depends on the type of AC, its efficiency, operating conditions, and the humidity level you are trying to control. Air conditioners can remove moisture from indoor air as part of the cooling process. A dedicated dehumidifier, on the other hand, is specifically designed to remove moisture.

If your primary goal is humidity control, a dehumidifier may be more appropriate because you don't necessarily need to cool the entire room. If you also need cooling, an AC unit can address both temperature and humidity at the same time. The most economical option depends on your climate, appliance efficiency, desired indoor temperature, and electricity rate.

What's the Cheapest Time of Day to Run a Dehumidifier?

If you're on a time-of-use electricity tariff, the cheapest time to run a dehumidifier is usually during your tariff's off-peak hours, when electricity costs less. Off-peak times vary by supplier and tariff, so check your electricity plan rather than assuming that nighttime electricity is always cheaper.

If you pay the same unit rate throughout the day, there is no cost advantage to running your dehumidifier at a particular time.

If you have solar panels, running the dehumidifier when your system is generating surplus electricity can also reduce the amount of grid electricity you use. With battery storage, surplus solar energy or electricity charged during cheaper off-peak periods can be stored for use later.