Dehumidifiers are one of the cheapest ways to beat condensation and dry washing indoors, but costs vary a lot between types. Choose your dehumidifier, set how long you run it, and see the cost per hour, day, month and year.
Dehumidifier running cost calculator
– · Default price: Ofgem price cap average, 1 Oct–31 Dec 2026. Check your bill for your exact unit rate.
How much does a dehumidifier cost to run?
At 26p per kWh:
| Dehumidifier | Typical power | Per hour | 6 hours a day for a month |
|---|---|---|---|
| Mini / Peltier | ~25 W | 0.7p | ~£1.20 |
| Compressor, 10–12 L | ~160 W | 4p | ~£7.50 |
| Compressor, 20 L | ~250 W | 6.5p | ~£11.70 |
| Desiccant (laundry / low) | ~300 W | 8p | ~£14 |
| Desiccant (high) | ~650 W | 17p | ~£30 |
Most dehumidifiers have a humidistat: once the room reaches the humidity you've set, the compressor or heater switches off, so real costs are often lower than these full-power figures.
Compressor or desiccant: which is cheaper?
- Compressor dehumidifiers are cheaper to run in heated rooms (above about 15°C), so they're the best choice for most UK homes.
- Desiccant dehumidifiers use more power but work better in cold rooms, garages and conservatories, and give off gentle warmth.
To dry washing, put a compressor dehumidifier and your airer in a small room with the door shut. The smaller the space, the faster and cheaper it dries. Full guide: does a dehumidifier dry clothes?
FAQs
How much does it cost to run a dehumidifier for 24 hours?
A 160 W compressor model running non-stop uses about 3.8 kWh, roughly £1 a day at 26p per kWh. With a humidistat it will usually use less.
Is it expensive to run a dehumidifier all day?
Not usually. A compressor dehumidifier typically costs 4–7p an hour, far less than a tumble dryer or an electric heater.
Is a dehumidifier cheaper than a tumble dryer?
Yes, for most homes. Drying a load with a compressor dehumidifier costs around 25–40p, compared with roughly 78p–£1.30 for a vented or condenser tumble dryer.
What setting should I put my dehumidifier on?
Around 50% relative humidity for everyday use; use laundry mode or the lowest setting when drying clothes.