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❄️ Cooling & Air

How Much Does a Window Air Conditioner Cost to Run?

At the current U.S. average rate of 18.8¢/kWh (April 2026), a window air conditioner costs about $41.15 per month at typical usage — 8 hours/day.

Per hour

$0.17

at 500–1,500 W

Per day

$1.35

8 hours/day

Per month

$41.15

219 kWh

Per year

$494

2,628 kWh

Window units draw 500–1,500 watts depending on size, and cooling a single occupied room this way is far cheaper than running central air for the whole house. Efficiency varies widely — a modern inverter unit can halve the cost of a decade-old one.

Calculate it for your home

Per hour

$0.17

Per day

$1.35

Per month

$41.15

Per year

$494

Uses 219 kWh/month at 18.8¢ per kWh.

Cheapest and most expensive states

Monthly cost at typical usage, using each state's current average residential rate.

North Dakota $27.14
Idaho $27.80
Nebraska $29.11
Oklahoma $29.11
Utah $29.11
U.S. average $41.15
New York $64.57
Massachusetts $64.57
Connecticut $70.48
California $77.26
Hawaii $102

Cost in every state

State Rate (¢/kWh) Per hour Per month Per year
North Dakota 12.4 $0.11 $27.14 $326
Idaho 12.7 $0.11 $27.80 $334
Nebraska 13.3 $0.12 $29.11 $350
Oklahoma 13.3 $0.12 $29.11 $350
Utah 13.3 $0.12 $29.11 $350
Iowa 13.9 $0.13 $30.42 $365
Montana 13.9 $0.13 $30.42 $365
Missouri 14.0 $0.13 $30.64 $368
Arkansas 14.2 $0.13 $31.08 $373
Nevada 14.3 $0.13 $31.30 $376
Louisiana 14.4 $0.13 $31.52 $378
Washington 14.4 $0.13 $31.52 $378
South Dakota 14.5 $0.13 $31.74 $381
Wyoming 14.7 $0.13 $32.18 $386
Tennessee 14.9 $0.13 $32.61 $392
Kentucky 15.0 $0.14 $32.83 $394
New Mexico 15.2 $0.14 $33.27 $399
Florida 15.4 $0.14 $33.71 $405
Georgia 15.4 $0.14 $33.71 $405
Arizona 15.5 $0.14 $33.93 $407
Kansas 15.8 $0.14 $34.58 $415
Oregon 15.8 $0.14 $34.58 $415
West Virginia 16.1 $0.14 $35.24 $423
North Carolina 16.3 $0.15 $35.68 $428
Minnesota 16.4 $0.15 $35.90 $431
Colorado 16.5 $0.15 $36.12 $434
Mississippi 16.8 $0.15 $36.77 $442
Texas 17.0 $0.15 $37.21 $447
South Carolina 17.1 $0.15 $37.43 $449
Alabama 17.4 $0.16 $38.09 $457
Virginia 17.4 $0.16 $38.09 $457
Indiana 17.9 $0.16 $39.18 $470
Delaware 18.8 $0.17 $41.15 $494
Wisconsin 19.2 $0.17 $42.02 $505
Ohio 19.5 $0.18 $42.68 $512
Illinois 20.5 $0.18 $44.87 $539
Michigan 21.4 $0.19 $46.84 $562
Pennsylvania 21.5 $0.19 $47.06 $565
Maryland 22.1 $0.20 $48.37 $581
New Jersey 23.5 $0.21 $51.44 $618
Vermont 24.6 $0.22 $53.84 $646
Washington, D.C. 25.4 $0.23 $55.60 $668
New Hampshire 27.2 $0.24 $59.54 $715
Alaska 27.4 $0.25 $59.97 $720
Rhode Island 28.3 $0.25 $61.94 $744
Maine 28.4 $0.26 $62.16 $746
Massachusetts 29.5 $0.27 $64.57 $775
New York 29.5 $0.27 $64.57 $775
Connecticut 32.2 $0.29 $70.48 $846
California 35.3 $0.32 $77.26 $928
Hawaii 46.6 $0.42 $102 $1,225

How to lower the cost

  • Buy the right size: an oversized unit short-cycles, dehumidifies poorly, and wastes energy.
  • Seal the gaps around the mounting panels — leaks pull in hot outdoor air continuously.
  • Use 'eco' or 'auto' mode so the compressor cycles off at temperature instead of running flat out.

Frequently asked questions

How much electricity does a window air conditioner use?

A typical window air conditioner draws about 900 watts in use. At 8 hours/day, that works out to roughly 7.2 kWh per day, or 219 kWh per month.

How much does it cost to run a window air conditioner for 1 hour?

At the current U.S. average residential rate of 18.8¢/kWh, one hour costs about $0.17. In North Dakota (12.4¢/kWh) it's $0.11, while in Hawaii (46.6¢/kWh) it's $0.42.

How much does a window air conditioner cost to run per month?

With typical usage (8 hours/day), expect about $41.15 per month at the U.S. average rate — from $27.14 in North Dakota up to $102 in Hawaii. Rates are as of April 2026.

Does a window air conditioner use a lot of electricity?

Yes — at typical usage it accounts for roughly 25% of an average U.S. home's monthly consumption (885 kWh), which makes it one of the larger loads in the house.

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