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Dishwasher Heated Dry vs. Air Dry: How Much Does Each Load Really Cost?

Dishwasher rack split down the middle, plates glowing with heated-dry warmth on one side and air-drying by a breeze icon on the other

On an ENERGY STAR certified dishwasher, heated dry costs less than about 10 cents a load at the US average electricity rate, and probably well under that. Switching to air dry is free, but it won’t move your bill much.

You’ll see exact per-load figures quoted online. None of the agency pages we checked publish one. What you can pin down is a ceiling, built from ENERGY STAR’s efficiency cap, and your own model’s exact number with a plug-in watt meter and two loads of dishes.

The ceiling: why heated dry can’t cost much on a certified machine

Step 1: what a whole cycle uses

ENERGY STAR caps a standard-size certified dishwasher at 240 kWh a year, assuming 215 cycles a year (about four a week). Drying energy is included in that total. So:

  • 240 kWh ÷ 215 cycles = about 1.12 kWh per complete cycle: washing, rinsing, heating water, and drying

At the US average residential rate of roughly 17–18¢ per kWh (from the EIA, the federal energy statistics agency):

  • 1.12 kWh × $0.17 = about 19¢
  • 1.12 kWh × $0.18 = about 20¢

That’s the rated ceiling for an entire certified cycle, before you even split out the drying.

Step 2: how much of that goes to drying

Lawrence Berkeley National Laboratory’s Home Energy Saver model splits dishwasher energy into two parts. Machine energy runs the pumps and the heating element for drying. Water heating energy heats the wash water. The lab says most of a dishwasher’s energy goes to heating water.

If water heating is more than half, then pumps plus drying together are less than half:

  • 1.12 kWh ÷ 2 = under about 0.56 kWh for pumps and drying combined
  • 0.56 kWh × $0.17 = 9.5¢; × $0.18 = 10¢

Heated dry is only part of that slice, since the pumps run on every cycle no matter how you dry. So on a certified standard dishwasher, heated dry costs less than about 10¢ a load.

Step 3: what that means over a year

Using ENERGY STAR’s 215 loads a year:

  • 0.56 kWh × 215 loads = about 120 kWh
  • 120 kWh × $0.17–$0.18 = about $20–$22 a year, as an upper limit for pumps and drying together

Your actual savings from switching off heated dry will be lower than that, because the pumps still run.

An ENERGY STAR cycle uses about 1.12 kWh, mostly for water heating; pumps plus drying are under half, so heated dry is under 10¢ a load

Older or non-certified dishwashers

The Berkeley Lab model assumes 0.78 kWh per load of machine energy for older machines, based on 1990 Department of Energy data. Machine energy covers pumps and drying heat, so for a dishwasher of that era:

  • 0.78 kWh × $0.17–$0.18 = about 13–14¢ a load for pumps and drying combined

Heated dry is again only part of that. An older machine may have more to gain from switching, but the per-load amount is still in the cents.

If your electricity costs more

Rates range from about 11¢ to over 40¢ per kWh by state, the EIA reports. Redo the arithmetic with the rate on your bill:

  • Per-load ceiling for pumps and drying = 0.56 kWh × your rate
  • At 40¢: 0.56 × $0.40 = about 22¢ a load

Measure your own: the two-load test

A plug-in watt meter measures what an appliance actually uses. The nameplate wattage is only its maximum draw, the Department of Energy notes. If your dishwasher plugs into an outlet, you can measure the cost of heated dry yourself.

  1. Plug the dishwasher into the meter. If it’s hardwired into a junction box instead of plugged in, skip this test. That connection is a job for an electrician, not a weekend experiment.
  2. Run a full load on your usual cycle with heated dry on. Write down the kWh reading at the end.
  3. Reset the meter. Run a similar full load on the same cycle with heated dry off. Write down that reading.
  4. Subtract. The difference is what heated dry uses on your machine.

Then do the math:

  • Cost per load = (kWh with heated dry − kWh without) × your rate per kWh
  • Cost per year = cost per load × the loads you run a year (ENERGY STAR assumes 215)

The meter reads only the electricity the dishwasher itself draws, not the energy your water heater uses to send it hot water. That’s fine for this test, because drying uses no extra hot water. As long as the wash portions match, the difference between the two loads comes down to drying.

Run both loads on the same day, if you can. Your tap water’s starting temperature can change the wash portion between days.

The bigger levers on the same machine

If heated dry is worth a few cents, where’s the rest of the energy? Mostly in heating water, according to Berkeley Lab. These habits address that:

  • Pick the eco cycle. Natural Resources Canada says most people choose the same program every time, usually a high-temperature one. It recommends eco mode instead.
  • Scrape, don’t rinse. ENERGY STAR and Natural Resources Canada both say there’s no need to pre-rinse dishes. Rinsing under a hot tap uses water your water heater has to heat.
  • Run full loads. That’s ENERGY STAR’s advice, and Berkeley Lab’s model ties dishwasher energy directly to the number of loads washed.

If you’re shopping, ENERGY STAR lists the ability to turn off heated dry as a feature to look for. Natural Resources Canada says certified models use an average of 12% less energy and 30% less water than standard ones.

For more zero-cost changes like these, see no-cost habits that lower an electric bill. And if you’re hunting for the real energy hog in your home, here’s which appliance is quietly using the most electricity.

Making air dry work

The trade-off for skipping heat is time and damp plastics, not money. A few habits help:

  1. Open the door a few inches once the cycle ends, so the warm, humid air can escape instead of condensing back onto the dishes.
  2. Time the cycle to end when you’re around to open the door, rather than letting it finish overnight and sit closed.
  3. Use rinse aid if your dishes come out spotty or wet. Your owner’s manual says where the dispenser is and how to set it.
  4. Load for drainage. Tip cups and bowls so water runs off rather than pooling, and don’t crowd the racks. The same loading habits that get dishes cleaner help them dry.

Plastic containers are the usual holdouts. If you need them dry right away, towel them off. That’s still cheaper than running the heat for a whole load.

Choose air dry if you can open the door after the cycle and your loads are mostly glass, ceramic, and metal. Keep heated dry if you run the dishwasher overnight and need dry dishes in the morning. At a few cents a load, convenience is a fair reason either way.

FAQ

Does heated dry clean or sanitize dishes better?

None of the sources here credit heated dry with cleaning or sanitizing; it’s the drying stage, after the wash and final rinse. Some models have a separate sanitize option. That’s a different setting from heated dry, so check your manual for what it does.

Is it cheaper to wash by hand and let dishes air-dry on a rack?

No. ENERGY STAR says a certified dishwasher uses less than half as much energy as washing by hand and saves about 8,400 gallons of water a year. It also estimates savings of about $220 a year and over 230 hours of your time. By ENERGY STAR’s comparison, a certified dishwasher comes out ahead on energy, water, money, and time.

What does it cost to run a dishwasher overall?

ENERGY STAR says a standard certified dishwasher costs about $50 a year to run. By the ceiling above, pumps and drying together account for under about $20–22 of that, and heated dry is only part of that slice.

Sources

Written and reviewed by peter.bae for Hearth & Habit · Last reviewed October 11, 2026

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