Illinois electric bills

Data through August 2026. Updated November 6, 2026.

What Illinois homes pay

Residential customers in Illinois paid an average of 19.3¢ per kWh in August 2026, up 7.2% from 18.0¢ in August 2025. Compared with August 2023, when it was 13.7¢, the price has moved +40.6%. Over the 12 months through August 2026 the average was 19.1¢, which puts Illinois above the middle state at 15.8¢ and 16th highest among the states and DC. States closest in price are Wisconsin (18.8¢), Ohio (18.4¢), Delaware (18.1¢), Pennsylvania (20.9¢).

Monthly average revenue per kWh, all residential customers. Source: EIA Form EIA-861M.

The highest monthly average in our records is 23.9¢ (May 2026) and the lowest is 13.7¢ (August 2023). These averages include fixed charges, so they typically move a little with the seasons even without a rate change: usage rises in peak months and spreads those fixed costs over more kWh. Your own price depends on your utility and plan, and can differ from the state figure by a wide margin.

How weather moves Illinois bills

We compared monthly federal usage records with NOAA temperature data for Illinois. For the average home, each extra 100 cooling degree days has gone with about 208 more kWh in a month, and each extra 100 heating degree days with about 31 more kWh. In Illinois, heat has moved usage more than cold has, per degree day. At 19.1¢, 100 cooling degree days works out near $40 and 100 heating degree days near $6.

Put the actual weather and prices together, and an average-use home's bill over the past 12 months would have peaked around July at about $201 and bottomed around October at about $101. That is a seasonal swing of about $101 with nothing unusual going on, so comparing a July bill to an October bill says little. Use the same month a year apart when you can.

Model estimates using state price and degree days, not actual billed amounts. The model's accuracy on data it had not seen (R²) was 0.97. How we test this.

Reading a state average

A state figure is a useful yardstick but doesn't describe your bill. Different utilities within Illinois can charge noticeably different prices, and your plan may include tiers, time-of-use pricing or a separate supplier. If your all-in price (total bill divided by kWh) sits far above 19.3¢, read your plan and fixed charges closely. In a low-usage month, a fixed charge alone can do that. Our guide to reading your bill shows which lines to compare, and the high bill checklist covers what to do if usage is the issue.

Common questions

What is the average electricity price in Illinois?

The average residential price was 19.3¢ per kWh in August 2026, the latest federal figure. The 12-month average was 19.1¢. Your own rate depends on your utility and plan.

Are Illinois electric rates going up?

The state average was up 7.2% from 18.0¢ a year earlier. One month's comparison is not a forecast, and it can differ from your utility's change.

How much does weather affect a Illinois electric bill?

About 208 kWh for each extra 100 cooling degree days and 31 kWh for each extra 100 heating degree days, for an average home in the state. Your home may respond quite differently.

Which month has the highest electric bill in Illinois?

Over the past 12 months our model put the average peak near July and the low near October. This is a statewide estimate and can vary by location and heating type.

Where does this data come from?

Prices come from the U.S. Energy Information Administration's Form EIA-861M through August 2026. Weather comes from NOAA, through October 2026. Both are statewide figures.