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

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

The short answer

Running a 900W window air conditioner in Connecticut costs about $0.22 an hour. At 8 hours a day, that’s roughly $52.92 a month and $635 a year.

That’s based on Connecticut’s average residential rate of 24.2¢/kWh (EIA, July 2026), 32% above the US average.

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

Window Air Conditioner cost by daily use in Connecticut

Cost at 24.2¢/kWh, the Connecticut average (EIA, Jul 2026)
Daily usekWh/monthPer dayPer monthPer year
1 hour/day 27.4 $0.22 $6.61 $79.37
2 hours/day 54.8 $0.43 $13.23 $159
4 hours/day 109.5 $0.87 $26.46 $317
8 hours/day 219.0 $1.74 $52.92 $635
12 hours/day 328.5 $2.61 $79.37 $952
24 hours/day 657.1 $5.22 $159 $1,905

Connecticut vs other states

At typical use, a window air conditioner costs $635 a year in Connecticut — $627 less than in Hawaii and $301 more than in Louisiana.

Connecticut has the 11th-most-expensive residential electricity of the 50 states and DC. Connecticut price per kWh · all states ranked

Electricity price trend in Connecticut

24.2¢/kWh in July 2026 — ▼ −12.5% 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.
  • Summers in Connecticut are relatively mild, so cooling costs are concentrated in a few hot weeks each year.

Questions

Frequently asked questions

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

Running a 900W window air conditioner for 24 hours uses about 21.6 kWh, which costs about $5.22 at Connecticut’s average rate of 24.2¢/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 Connecticut that costs $52.92.

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

Connecticut has the 11th-most-expensive residential electricity of the 50 states and DC at 24.2¢/kWh — pricier than most. Running a window air conditioner here costs about $635 a year at typical use, compared with $481 at the national average rate.

What is the electricity rate in Connecticut right now?

The average residential electricity rate in Connecticut was 24.2¢ per kWh in July 2026, according to the latest EIA data — down 12.5% 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.

Window Air Conditioner costs in nearby states

Cheapest and priciest states

Comparisons

Sources & method