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CostPerKWh

Cost to run a window AC

A window or portable air conditioner draws its BTU rating divided by its efficiency ratio in watts while the compressor runs. Pick your state or enter your own rate to see what it costs you.

Official EIA data · August 2026

BTU
h
days

BTU and CEER (Combined Energy Efficiency Ratio) are on the yellow EnergyGuide label. Watts ≈ BTU ÷ CEER.

EIA average residential price, August 2026. Your bill shows your exact rate.

Cost to run a window AC per month

$31.70

174.5 kWh at 18.16¢/kWh (U.S. average)

Per hour of use
$0.13
Per day of use
$1.06
Per year (same use every month)
$380.37

Power draw

727 W

0.73 kW

Energy per year

2,095 kWh

if used like this all year

Full details Costs in every state, real-world usage, formula and tips

Cost to run a window AC in every state

For an 8,000 BTU unit with a CEER of 11, running 8 hours a day, 30 days a month, at each state's average residential electricity rate (August 2026, EIA). Click a state for more detail.

StateRatePer hourPer monthPer year
Nevada 12.72¢ $0.09 $22.20 $266.43
Louisiana 12.87¢ $0.09 $22.46 $269.57
North Dakota 13.31¢ $0.10 $23.23 $278.78
Utah 13.31¢ $0.10 $23.23 $278.78
Idaho 13.37¢ $0.10 $23.34 $280.04
Tennessee 13.42¢ $0.10 $23.42 $281.09
Nebraska 13.54¢ $0.10 $23.63 $283.60
Kentucky 13.80¢ $0.10 $24.09 $289.05
Arkansas 14.37¢ $0.10 $25.08 $300.99
Mississippi 14.43¢ $0.10 $25.19 $302.24
Wyoming 14.43¢ $0.10 $25.19 $302.24
Washington 14.63¢ $0.11 $25.54 $306.43
Oklahoma 14.82¢ $0.11 $25.87 $310.41
North Carolina 14.95¢ $0.11 $26.09 $313.13
Florida 14.99¢ $0.11 $26.16 $313.97
Arizona 15.05¢ $0.11 $26.27 $315.23
South Dakota 15.15¢ $0.11 $26.44 $317.32
Kansas 15.47¢ $0.11 $27.00 $324.03
Montana 15.57¢ $0.11 $27.18 $326.12
South Carolina 15.76¢ $0.11 $27.51 $330.10
Georgia 15.90¢ $0.12 $27.75 $333.03
Texas 15.91¢ $0.12 $27.77 $333.24
Oregon 15.92¢ $0.12 $27.79 $333.45
Missouri 16.02¢ $0.12 $27.96 $335.55
West Virginia 16.31¢ $0.12 $28.47 $341.62
Alabama 16.33¢ $0.12 $28.50 $342.04
New Mexico 16.51¢ $0.12 $28.82 $345.81
Indiana 17.02¢ $0.12 $29.71 $356.49
Iowa 17.06¢ $0.12 $29.78 $357.33
Colorado 17.17¢ $0.12 $29.97 $359.63
Minnesota 17.20¢ $0.13 $30.02 $360.26
Virginia 17.64¢ $0.13 $30.79 $369.48
Delaware 18.70¢ $0.14 $32.64 $391.68
Illinois 19.32¢ $0.14 $33.72 $404.67
Ohio 19.38¢ $0.14 $33.83 $405.92
Wisconsin 19.41¢ $0.14 $33.88 $406.55
Maryland 21.40¢ $0.16 $37.35 $448.23
Pennsylvania 21.77¢ $0.16 $38.00 $455.98
Michigan 22.99¢ $0.17 $40.13 $481.54
Vermont 23.84¢ $0.17 $41.61 $499.34
Connecticut 24.51¢ $0.18 $42.78 $513.37
New Jersey 24.61¢ $0.18 $42.96 $515.47
District of Columbia 25.98¢ $0.19 $45.35 $544.16
New Hampshire 27.64¢ $0.20 $48.24 $578.93
Rhode Island 28.18¢ $0.20 $49.19 $590.24
New York 28.65¢ $0.21 $50.01 $600.09
Alaska 29.41¢ $0.21 $51.33 $616.01
California 29.75¢ $0.22 $51.93 $623.13
Massachusetts 30.48¢ $0.22 $53.20 $638.42
Maine 32.11¢ $0.23 $56.05 $672.56
Hawaii 47.18¢ $0.34 $82.35 $988.21

How the cost is calculated

Divide the cooling capacity by the efficiency ratio: BTU ÷ CEER = watts. An 8,000 BTU unit with a CEER of 11 draws about 730 W while the compressor runs.

How to lower the cost

  • Pick the size the ENERGY STAR chart recommends for the room; oversized units waste energy and leave the air clammy.
  • Seal the gaps around the unit with the foam panels that come with it.
  • Clean the filter every couple of weeks during the season.

Quick answers

How much does it cost to run a window AC per month?

At the U.S. average residential rate of 18.16¢ per kWh (August 2026), an 8,000 BTU unit with a CEER of 11, running 8 hours a day, 30 days a month uses about 175 kWh and costs about $31.70 a month, or $380.37 a year if used the same way all year.

How much does it cost to run a window AC per hour?

At 727 W it uses 0.73 kWh per hour, which costs $0.13 at the U.S. average rate, from $0.09 in Nevada to $0.34 in Hawaii.

Where is it cheapest to run a window AC?

Electricity prices vary a lot by state. In August 2026, Nevada had the lowest average residential rate (12.72¢/kWh) and Hawaii the highest (47.18¢/kWh). The same use costs $22.20 a month in Nevada and $82.35 in Hawaii.

Sources

Last reviewed November 2, 2026. Rates refreshed automatically when EIA publishes a new month.

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See everything

These are estimates. State rates are EIA averages (total residential revenue ÷ kWh sold), so they include fixed monthly charges spread across usage; your own price per kWh, time-of-use rates and taxes can differ. Real appliance use depends on the model, settings, climate and habits.