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❄️ Cooling & Air

How Much Does a Window Air Conditioner Cost to Run?

At the current U.S. average rate of 18.4¢/kWh (May 2026), a window air conditioner costs about $40.27 per month at typical usage — 8 hours/day.

Per hour

$0.17

at 500–1,500 W

Per day

$1.32

8 hours/day

Per month

$40.27

219 kWh

Per year

$484

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

$1.32

Per month

$40.27

Per year

$484

Uses 219 kWh/month at 18.4¢ per kWh.

Cheapest and most expensive states

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

Idaho $27.14
Utah $28.45
Oklahoma $29.33
Nebraska $29.77
Nevada $29.77
U.S. average $40.27
Massachusetts $63.04
Rhode Island $64.57
New York $65.45
California $72.89
Hawaii $114

Cost in every state

State Rate (¢/kWh) Per hour Per month Per year
Idaho 12.4 $0.11 $27.14 $326
Utah 13.0 $0.12 $28.45 $342
Oklahoma 13.4 $0.12 $29.33 $352
Nebraska 13.6 $0.12 $29.77 $357
Nevada 13.6 $0.12 $29.77 $357
North Dakota 13.6 $0.12 $29.77 $357
Missouri 13.7 $0.12 $29.99 $360
Iowa 14.1 $0.13 $30.86 $371
New Mexico 14.1 $0.13 $30.86 $371
Louisiana 14.2 $0.13 $31.08 $373
Arkansas 14.4 $0.13 $31.52 $378
Tennessee 14.5 $0.13 $31.74 $381
Montana 14.7 $0.13 $32.18 $386
Wyoming 14.8 $0.13 $32.39 $389
Kentucky 15.0 $0.14 $32.83 $394
Washington 15.0 $0.14 $32.83 $394
Kansas 15.1 $0.14 $33.05 $397
North Carolina 15.1 $0.14 $33.05 $397
Arizona 15.2 $0.14 $33.27 $399
Florida 15.2 $0.14 $33.27 $399
South Dakota 15.7 $0.14 $34.36 $413
Georgia 15.8 $0.14 $34.58 $415
Colorado 16.2 $0.15 $35.46 $426
Mississippi 16.2 $0.15 $35.46 $426
South Carolina 16.2 $0.15 $35.46 $426
Oregon 16.3 $0.15 $35.68 $428
Texas 16.4 $0.15 $35.90 $431
Alabama 16.8 $0.15 $36.77 $442
West Virginia 16.8 $0.15 $36.77 $442
Minnesota 17.0 $0.15 $37.21 $447
Virginia 17.6 $0.16 $38.52 $463
Indiana 18.2 $0.16 $39.84 $478
Delaware 19.4 $0.17 $42.46 $510
Ohio 19.5 $0.18 $42.68 $512
Wisconsin 19.7 $0.18 $43.12 $518
Pennsylvania 21.6 $0.19 $47.28 $568
Maryland 21.8 $0.20 $47.72 $573
Michigan 22.0 $0.20 $48.15 $578
New Jersey 23.3 $0.21 $51.00 $612
Illinois 23.9 $0.22 $52.31 $628
Vermont 24.9 $0.22 $54.50 $654
Washington, D.C. 25.4 $0.23 $55.60 $668
New Hampshire 27.3 $0.25 $59.75 $717
Connecticut 27.4 $0.25 $59.97 $720
Alaska 28.2 $0.25 $61.72 $741
Maine 28.6 $0.26 $62.60 $752
Massachusetts 28.8 $0.26 $63.04 $757
Rhode Island 29.5 $0.27 $64.57 $775
New York 29.9 $0.27 $65.45 $786
California 33.3 $0.30 $72.89 $875
Hawaii 52.0 $0.47 $114 $1,367

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 18.4¢/kWh, one hour costs about $0.17. In Idaho (12.4¢/kWh) it's $0.11, while in Hawaii (52¢/kWh) it's $0.47.

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

With typical usage (8 hours/day), expect about $40.27 per month at the U.S. average rate — from $27.14 in Idaho up to $114 in Hawaii. Rates are as of May 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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