Find out exactly what your dehumidifier costs to run in the UK — work out the cost per hour and per month from the wattage and your daily usage pattern.
Dehumidifier cost · Per hour to per year · UK p/kWh
Check the rating plate. Most home dehumidifiers draw 150–700 W; mini peltier units far less.
Multiply the power rating in kW (watts ÷ 1000) by the hours you run it, then multiply by your electricity unit rate in pence. Divide by 100 to convert to pounds. A 200 W dehumidifier running 8 hours a day at 24.5p/kWh costs about 39p per day and £11.89 per month.
The calculator above handles the arithmetic and breaks costs down per hour, day, month and year. Change the wattage, hours, or unit rate and all figures update instantly.
The biggest factor in running cost is the type of dehumidifier. Compressor models are more efficient in warm rooms; desiccant models work better in cold spaces but draw more power. Use the presets in the calculator to compare types side by side.
Mini peltier units are the cheapest to run but extract very little moisture — suitable only for small spaces like wardrobes or caravans, not whole rooms.
A typical 200 W compressor dehumidifier costs about 4.9p per hour at 24.5p/kWh (200 ÷ 1000 × 24.5 = 4.9p). A desiccant unit drawing 600 W costs around 14.7p per hour. Enter your exact wattage in the calculator above for a personalised figure.
At 8 hours a day, a 200 W dehumidifier uses 1.6 kWh and costs around 39p a day at 24.5p/kWh. A 600 W desiccant unit run for the same time would cost around £1.18 per day. Use the calculator to adjust for your actual usage hours.
A 200 W dehumidifier run for 8 hours every day costs roughly £11.89 a month at 24.5p/kWh. A 600 W desiccant model under the same conditions would be closer to £35.67 a month. If you only run it a few days a week, use the "days per week" control to get a more accurate estimate.
Compared to a 2 kW electric heater (about 49p/hr), most dehumidifiers are relatively cheap to run — 5–15p per hour for typical home models. The total cost depends heavily on how many hours a day and days a week you use it. Running one 8 hours a day all year at 200 W would cost around £143 annually at 24.5p/kWh.
In most cases, yes. A 200 W dehumidifier costs about 4.9p an hour versus 49p/hr for a 2 kW electric heater. In damp homes, removing moisture can also make existing heating feel more effective, since dry air holds heat better than humid air — so a dehumidifier may reduce the amount of heating needed.
Compressor dehumidifiers typically draw 150–300 W and are cheaper to run in warm rooms (above 15°C). Desiccant models draw 300–700 W but work well in cold rooms such as garages and conservatories. At 24.5p/kWh, a 200 W compressor costs about £11.89/month (8 hrs/day) while a 500 W desiccant unit costs roughly £29.67/month — nearly 2.5× more.
Running a dehumidifier continuously is rarely necessary once the room reaches your target humidity (typically 40–60% RH). Many modern units have a built-in humidistat and will cycle on and off automatically. Setting a target humidity and letting the unit self-regulate is more cost-effective than running it on full-time.
Relative to other home appliances, dehumidifiers are moderate electricity users. A 200 W model uses 1.6 kWh over 8 hours — less than a single wash cycle in most washing machines. However, because dehumidifiers are often left running for many hours a day, cumulative consumption can be significant. The annual cost for an 8-hour-a-day 200 W unit is around £143 at 24.5p/kWh.
