Illinois has about 200,000 residential pools, one for every 64 residents. Here is what running one costs at Illinois's electricity price, and the calculators to keep yours clear.
Electricity in Illinois averages 19.32 cents per kWh, above the median state's 16.32 cents. For a typical 20,000-gallon pool turned over in 8 hours a day:
| Pump | Per month | Per year, if run year-round |
|---|---|---|
| Single-speed, 1.7 kW, 8 h a day | $79.88 | $959 |
| Variable-speed at half speed, 16 h a day | $19.97 | $240 |
Switching saves about $59.91 a month in Illinois. Run your own pump and pool size in the pool pump calculator, already set to Illinois's price.
A covered spa whose 4 kW heater runs about 2 hours a day, with a 300 W pump on for 12 hours, uses about 353 kWh a month: $68.13 a month at Illinois prices.
Heater time is the big variable: a cold winter or a waterlogged cover can double it. Enter your own numbers in the hot tub electricity cost calculator.
Wherever you swim, clear water comes down to a few numbers: free chlorine at 7.5% of your stabilizer or more, pH between 7.2 and 7.8, and enough pump time to filter all the water every day. Sunny, hot weeks use chlorine fastest, so test more often then.
About 200,000 residential pools, one for every 64 residents. That ranks Illinois 11th of 50 states for the number of pools and 33rd for pools per person.
At Illinois's average residential electricity price of 19.32 cents per kWh, a 1.7 kW single-speed pump running 8 hours a day costs about $79.88 a month. A variable-speed pump moving the same water at half speed costs about $19.97.
About $68.13 a month for a spa whose 4 kW heater runs 2 hours a day and whose 300 W pump runs 12 hours, at 19.32 cents per kWh. Your heater time depends on weather and your cover.
How to Raise pH in a Pool: Soda Ash, Aeration or BoraxLow pool pH stings eyes and eats equipment. Here's how to raise it with aeration, soda ash or borax, how much to start with, and why it keeps dropping.
Pool Green but Chlorine Is High? 4 Real Causes and FixesA green pool with a high chlorine reading usually means metals, too much stabilizer, a misleading test or pollen. Here's how to tell which one you have and what to do.
Pool Salt Cell Guide: How It Works, Cleaning and Low Salt ReadingsHow a pool salt cell makes chlorine, how to clean it, how long it lasts, and why it reads 'low salt' when the water isn't. A practical guide for salt pool owners.Sources: pool counts from RubyHome, Swimming Pool Statistics (2026); electricity prices from US EIA, Electric Power Monthly, Table 5.6.A, residential price, August 2026. Costs are estimates for the setups described.