Dehumidifiers use moderate to high energy compared to most household appliances, but the actual cost depends on the unit's size, how often it runs, and your local electricity rate

A typical dehumidifier draws between 300 and 700 watts while running. To put that in perspective, a refrigerator uses about 150 to 800 watts depending on the model, and a window air conditioner uses 900 to 1,440 watts. A dehumidifier sits in the middle—not the heaviest user in your home, but not light either.

If you run a 500-watt dehumidifier for 8 hours a day, that's 4 kilowatt-hours (kWh) per day, or roughly 120 kWh per month. At the U.S. average electricity rate of about 16 cents per kWh (rates vary significantly by region and utility), that works out to around $19 per month. Running it 24 hours a day would cost roughly $57 per month. The actual number for your home depends on your local rate, which you can find on your electric bill.

Key Takeaways

  • Most dehumidifiers draw 300 to 700 watts, placing them in the moderate-to-high range for household appliances.
  • Running a 500-watt unit for 8 hours daily costs roughly $19 per month at average U.S. electricity rates, though your rate may be higher or lower.
  • Larger units and continuous operation increase energy use; smaller units and shorter run times reduce it significantly.
  • Energy Star certified dehumidifiers use about 15 percent less electricity than standard models of the same capacity.
  • The cost of running a dehumidifier is usually less than the cost of water damage or mold remediation if humidity stays unchecked.

What determines how much energy a dehumidifier draws

The wattage printed on a dehumidifier's label is its maximum draw—the amount it uses when the compressor is running at full capacity. Most units do not run continuously at that level. A dehumidifier cycles on and off as the room humidity rises and falls, so the actual average draw is often 30 to 50 percent lower than the rated wattage.

Larger units (those rated to remove 50 or more pints of moisture per day) draw more power than smaller ones. A 30-pint dehumidifier typically uses 300 to 400 watts, while a 70-pint model uses 600 to 800 watts. The size you need depends on the room—a small bedroom may need only 30 pints per day, while a damp basement might need 50 or 70.

How often the unit runs also matters. In a very humid space, the dehumidifier runs more frequently and uses more total energy. In a space that is already fairly dry, it cycles on less often. If you set the target humidity to 50 percent, the unit will run less than if you set it to 35 percent.

Comparing dehumidifier energy use to other appliances

A 500-watt dehumidifier uses less energy than a typical electric water heater (4,000 to 5,500 watts) or a clothes dryer (3,000 to 5,000 watts), but more than a ceiling fan (50 to 100 watts) or a television (100 to 200 watts). It uses roughly the same amount as a microwave oven (1,000 watts, but only when actively heating) or a dishwasher (1,800 to 2,400 watts, but only during the wash and dry cycles).

The key difference is that a dehumidifier often runs for many hours per day or continuously, whereas a dishwasher or microwave runs for minutes. That continuous or near-continuous operation is what makes the monthly cost add up, even though the wattage itself is not extreme.

How to estimate your actual monthly cost

Find your dehumidifier's wattage on the label or in the manual. Multiply that by the number of hours per day you expect it to run, then multiply by 30 days. Divide by 1,000 to convert to kilowatt-hours. Then multiply by your local electricity rate (in dollars per kWh) to get the monthly cost.

Example: A 500-watt dehumidifier running 12 hours per day would use (500 × 12 × 30) ÷ 1,000 = 180 kWh per month. At 16 cents per kWh, that is 180 × $0.16 = $28.80 per month. If your rate is 12 cents per kWh, the cost drops to $21.60. If it is 20 cents per kWh, it rises to $36.

Your electricity rate is listed on your monthly utility bill, usually as cents per kWh or kilowatt-hour. Rates vary widely by state and utility—Louisiana averages around 9 cents per kWh, while Hawaii averages over 30 cents per kWh.

Energy Star dehumidifiers versus standard models

Energy Star certified dehumidifiers use approximately 15 percent less electricity than non-certified models of the same capacity. An Energy Star 50-pint unit might draw 450 watts instead of 530 watts. Over a month of continuous operation, that difference adds up to roughly $10 to $15 in savings, depending on your rate and run time.

Energy Star models cost more upfront—typically $50 to $150 more than a comparable standard unit. If you plan to run the dehumidifier year-round or for many hours daily, the energy savings will offset that premium within one to two years. If you use it seasonally or for a few hours a day, the payback period is longer.

When the cost of running a dehumidifier is worth it

The monthly electricity cost of a dehumidifier is usually far less than the cost of water damage, mold remediation, or health problems caused by high humidity. Mold removal from a basement can cost $2,000 to $6,000 or more. Structural damage from moisture can cost tens of thousands. A dehumidifier running for $20 to $60 per month is inexpensive insurance against those outcomes.

High humidity also makes air conditioning work harder and less efficiently. In a humid space, your AC unit may run longer to reach the target temperature, offsetting some of the dehumidifier's energy cost. Removing moisture from the air can actually lower your total cooling costs in summer.

If you are running a dehumidifier in a space where humidity is not a real problem—a dry climate or a well-sealed, climate-controlled room—then the cost is pure expense with no benefit. But in a basement, bathroom, laundry room, or humid climate, the cost is usually justified.

Ways to reduce dehumidifier energy use

Set the target humidity to 50 to 55 percent rather than lower. Each percentage point lower requires the unit to run longer and use more energy. A setting of 50 percent is low enough to prevent mold and dust mites in most homes.

Run the dehumidifier only when needed. If your space is naturally dry in winter, turn the unit off. If humidity is high only during certain hours, use a timer or smart plug to run it only during those times. Closing doors to isolate the dehumidifier to one room also reduces the work it has to do.

Empty the water collection bucket or drain it continuously. A full bucket forces the unit to shut off, and you lose the benefit of running it. A clogged or dirty filter also makes the unit work harder, so clean or replace the filter according to the manufacturer's schedule.

Improve ventilation and air flow. Running a bathroom exhaust fan during and after showers, venting a clothes dryer outside, and opening windows on dry days all reduce the moisture load the dehumidifier has to handle.

Frequently Asked Questions

Is it cheaper to run a dehumidifier or an air conditioner?

An air conditioner uses more power (900 to 1,440 watts) than a dehumidifier (300 to 700 watts), so running the AC is more expensive per hour. However, an AC removes moisture while cooling, so if you need both, running the AC alone may be more cost-effective than running both a dehumidifier and a fan. In humid climates, the AC will run longer and use more energy overall because it has to remove moisture before it can cool effectively.

Do dehumidifiers use more energy in winter or summer?

Dehumidifiers typically use more energy in summer because outdoor humidity is higher and the unit runs more frequently. In winter, especially in cold climates, indoor humidity is often naturally low, so the dehumidifier runs less or not at all. In humid climates or in homes with poor ventilation, winter humidity can still be high enough to require regular dehumidifier use.

Can I use a dehumidifier to lower my electric bill?

Not directly—a dehumidifier adds to your electric bill. However, by removing moisture from the air, it can make your air conditioner run more efficiently in summer, which may reduce your overall cooling costs. The net effect depends on your climate, how much you run the AC, and how often you run the dehumidifier.

What size dehumidifier uses the least energy?

The smallest unit that can handle your room's moisture load uses the least energy. A 30-pint dehumidifier uses less power than a 70-pint model, but if your room needs 70 pints of removal per day, a 30-pint unit will run constantly and use more total energy. Choose the right size for your space, then look for Energy Star certification to reduce energy use further.

Do dehumidifiers use more energy if the room is very humid?

Yes. In a very humid space, the dehumidifier runs more frequently and for longer periods, so total energy use is higher. The unit's wattage stays the same, but the number of hours it runs per day increases. This is another reason to address the source of humidity—poor ventilation, water leaks, or outdoor moisture—rather than relying on the dehumidifier alone.