U.S. residential electricity EIA data: July 2026 US average 18.3¢/kWh Updated

Cooling · Washington

How Much Does It Cost to Run a Window Air Conditioner in Washington?

The short answer

Running a 900W window air conditioner in Washington costs about $0.13 an hour. At 8 hours a day, that’s roughly $32.22 a month and $387 a year.

That’s based on Washington’s average residential rate of 14.7¢/kWh (EIA, July 2026), 20% below the US average.

Source: U.S. EIA, July 2026 data · Updated

Window Air Conditioner cost by daily use in Washington

Cost at 14.7¢/kWh, the Washington average (EIA, Jul 2026)
Daily usekWh/monthPer dayPer monthPer year
1 hour/day 27.4 $0.13 $4.03 $48.32
2 hours/day 54.8 $0.26 $8.05 $96.64
4 hours/day 109.5 $0.53 $16.11 $193
8 hours/day 219.0 $1.06 $32.22 $387
12 hours/day 328.5 $1.59 $48.33 $580
24 hours/day 657.1 $3.18 $96.66 $1,160

Washington vs other states

At typical use, a window air conditioner costs $387 a year in Washington — $875 less than in Hawaii and $52.30 more than in Louisiana.

Washington has the 13th-cheapest residential electricity of the 50 states and DC. Washington electricity rates · all states ranked

Electricity price trend in Washington

14.7¢/kWh in July 2026 — ▲ +9.4% from a year earlier.

How to lower the cost of running a window air conditioner

Window air conditioners cool a single room and are far cheaper to run than central AC when you only need one or two rooms cool. Wattage scales with capacity: small 5,000 BTU units draw around 450–500W, a 10,000 BTU unit around 900W, and large 15,000+ BTU units 1,300–1,500W. ENERGY STAR models with inverter compressors can use 20–35% less. The compressor cycles with the thermostat, so enter the hours it actually runs.

  • Pick the right size — an oversized unit cycles constantly and dehumidifies poorly.
  • Seal the gaps around the unit with foam strips to keep hot air out.
  • Clean the washable filter every two weeks in peak season.

Questions

Frequently asked questions

How much does it cost to run a window air conditioner for 24 hours in Washington?

Running a 900W window air conditioner for 24 hours uses about 21.6 kWh, which costs about $3.18 at Washington’s average rate of 14.7¢/kWh.

How many kWh does a window air conditioner use per month?

At 8 hours a day, a typical window air conditioner uses about 219 kWh a month. In Washington that costs $32.22.

Is it expensive to run a window air conditioner in Washington?

Washington has the 13th-cheapest residential electricity of the 50 states and DC at 14.7¢/kWh — cheaper than most. Running a window air conditioner here costs about $387 a year at typical use, compared with $481 at the national average rate.

What is the electricity rate in Washington right now?

The average residential electricity rate in Washington was 14.7¢ per kWh in July 2026, according to the latest EIA data — up 9.4% from a year earlier.

Is a window AC cheaper to run than central air?

For cooling one or two rooms, yes. A 900W window unit uses about a quarter of the power of a typical 3,500W central system.

Sources & method