Updated August 24, 2026
Dehumidifier Running Cost Calculator
Free dehumidifier running cost calculator. See how much it costs to run a dehumidifier per hour, day, month, and year using your electricity rate.
Live calculator
Calculate your actual running cost
Running this dehumidifier for 8 hours a day, 7 days a week uses about 72.8 kWh each month.
Quick answer
How much does a dehumidifier cost to run?
A 300 W dehumidifier used for 8 hours a day, 7 days a week, consumes about 72.8 kWh per month. At £0.2611 per kWh (Ofgem GB illustration for Jul–Sep 2026), that is approximately £19.01 per month. Replace these example figures with the wattage and electricity rate from your appliance and bill.
What changes the real running cost?
Dehumidifier power use depends on its type, capacity, humidity target, and room temperature. Compressor models also cycle as the target humidity is reached.
Use effective compressor hours for a realistic estimate, or measure a full day with a plug-in electricity meter.
Assumptions used in this example
This page starts with 300 watts, 8 hours of use per day, and 7 days per week. Those defaults are only a practical starting point. Replace them with the number on your product label, energy label, smart plug, or electricity bill.
Example dehumidifier costs
These examples use 300 W for 8 hours a day and 7 days per week.
| Electricity rate | Per hour | Per month | Per year |
|---|---|---|---|
| £0.20 / kWh | £0.06 | £14.56 | £174.72 |
| £0.26 / kWh | £0.08 | £19.01 | £228.10 |
| £0.35 / kWh | £0.10 | £25.48 | £305.76 |
Ways to reduce the cost
Start with changes that reduce active runtime without compromising safety or the job the appliance needs to do.
- Close doors and windows while it runs.
- Choose a realistic humidity target.
- Clean the filter on the manufacturer's schedule.
Estimate only. Actual consumption varies by model, setting, condition, temperature, duty cycle, and tariff. Use a plug-in meter or energy-label figure when accuracy matters.
FAQ
Dehumidifier running cost questions
How do I calculate dehumidifier running cost?
Divide the watts by 1,000 to get kilowatts, multiply by the hours used, then multiply by your electricity price per kWh. This page pre-fills 300 W, 8 hours per day, and 7 days per week as a starting example.
How much does a dehumidifier cost per hour?
At 300 W and £0.2611 per kWh (an Ofgem GB cap illustration), the example cost is about £0.08 per hour while it is actively using that power. Change the rate field to match your own bill.
Why might my real dehumidifier cost be different?
Use effective compressor hours for a realistic estimate, or measure a full day with a plug-in electricity meter.
Should I use rated watts or measured watts?
Rated watts are useful for a quick estimate, but measured wall power or an energy-label kWh figure is usually more accurate because many appliances cycle on and off or change power during use.
Does the calculator include standing charges, taxes, or demand charges?
No. The calculator estimates usage cost from kWh only. If your bill includes standing charges, taxes, delivery fees, or demand charges, add those separately.
Can I share my result?
Yes. Use the share or copy button after entering your wattage, hours, days, rate, and currency. The page stores those inputs in the URL so you can revisit the same estimate.