Illinois price to compare: ComEd and Ameren, and how to test an offer against it

It is the price per kWh your utility charges for the power itself if you pick no supplier. Plug In Illinois, the Commission's shopping site, adds two charges to get it: the electric supply charge and the transmission charge. Transmission pays for the high-voltage lines that carry power to your area.

Your bill has a third part, delivery. You pay it to the utility whether or not you buy from a supplier. A supplier can only replace the supply and transmission parts, which is why the price to compare is the number to beat.

Plug In Illinois also lists Ameren's pieces: supply of 7.310¢ (first 800 kWh) or 5.131¢ (above), transmission of 2.765¢ and a supply cost adjustment of 0.313¢. On October 25, 2026, those listed pieces did not add up exactly to the stated totals, so this page uses the stated totals and does not add the pieces up.

Look at the top of your electric bill. If it says ComEd, use ComEd's number. If it says Ameren Illinois, use Ameren's. In general, ComEd serves northern Illinois, including Chicago, and Ameren Illinois serves most of central and southern Illinois.

Your ZIP code alone can mislead you, because a utility's area does not follow ZIP lines. The Commission also lists MidAmerican as its own area, and a city-owned utility or a co-op may not be part of the choice program. If that is you, the numbers on this page do not apply.

For where the number came from and why bills are rising, read our ComEd price reset guide and Ameren bill guide. This page is about using the number.

Type the offer's price per kWh, any monthly fee and your use. The tool prices the utility's side the way the Commission does, with Ameren's two steps, and shows the saving or the extra cost each month and over the whole offer.

1. 1
   Pick your utility.

   It is on your bill.

2. 2
   Type the offer's price.

   Use cents per kWh, such as 11.49.

3. 3
   Add the fee, your kWh and the term.

   The offer sheet lists the fee and the months.

4. 4
   ComEd only: type your adjustment.

   It is the "Purchased Electricity Adjustment" line on your bill. Leave 0 if you do not have it.

"Costs less" is money you would keep. "Costs more" is money the offer would take from you. This is an estimate of the supply price only, not a bill, and it assumes both prices stay the same for the whole offer.

ComEd's monthly adjustment. The Commission says ComEd's price to compare does not include the Purchased Electricity Adjustment, or PEA. The PEA is a credit or a charge that trues up what ComEd paid for power against what it billed, and ComEd sets it each month. You do not pay it if you buy from a supplier.

That matters, because the PEA is not always near zero. The Commission's historical file, read Oct. 25, 2026, lists ComEd's PEA from a credit of 1.785¢ per kWh to a charge of 8.166¢ per kWh in the months since July 2023. The charge peak was May 2026. So on a month with a big charge, ComEd's real supply price is well above the price to compare, and an offer looks better than the table suggests.

The renewable charge no longer tips the scale. ComEd's Renewable Energy Adjustment is 1.690¢ per kWh for every customer from October 2026, whatever supplier they choose. Since it is the same either way, it should not change which offer wins.

Ameren's two steps. Ameren's price drops after 800 kWh. A flat offer price can win in a small month and lose in a big one, so check your biggest months too. Ameren also has a monthly adjustment on its bill. The Commission says it expects it to be close to zero and leaves it out of the price to compare.

Summer prices. Both utilities set a separate summer price from June to September. The next price starts the day after May 31, 2027. Plug In Illinois posts it when it is set, so no one can say today whether an offer will beat it.

Hourly pricing. If you are on ComEd's Hourly Pricing or Ameren's Power Smart Pricing, you do not pay the fixed price to compare, and this test does not fit you. The Commission says to compare your past supply cost with what an offer would have cost. ComEd's own Hourly Pricing site has a bill comparison tool for this.

We read the Commission's offer lists for each utility on October 25, 2026 and tested every priced offer at 1,000 kWh a month against the current price to compare. This is a snapshot by a person, not a live feed, because the Commission's site does not allow robots to read it.

Read the table against the price to compare at the top of this page. A fixed price of a year or more has to be lower than it to win, and the offers under it are often short, variable or carry a monthly fee. Some rows on the list also look incomplete, such as a price of zero with a monthly fee, so read any offer's own sheet.

One more catch: on October 25, 2026, the Commission's own ComEd and Ameren Zone I offer lists still described the utility's price as the one in effect June 1 to September 30, 2026, which was the summer number. Always check the current number on the Plug In Illinois ComEd or Ameren page, or use the number at the top of this page.

What a plan finder shows. On Oct. 25, 2026 the plan finder returned 4 plans for ComEd ZIP 60614, from 10.80¢ to 12.20¢ per kWh, all above ComEd's price to compare that day. It returned 3 plans for Ameren's Peoria ZIP 61602, from 11.20¢ to 15.00¢. Offers change daily, and so does the price to compare. The checker above tells you in seconds whether the one you like is worth it, and the finder button lets you see what is offered at your ZIP.

If you change your mind, Illinois gives you time. Plug In Illinois says residential and small commercial customers in ComEd and Ameren Illinois areas can cancel a supplier agreement within 10 days of the utility processing the enrollment. The utility sends a written notice of the switch and the supplier's name. If a supplier or utility does not do what it promised, the Commission takes complaints at (800) 524-0795.

Your delivery stays with ComEd or Ameren, so the lights, outages and meter are still theirs. Check our Illinois electric rates guide for what else is on your bill.

Plug In Illinois posts only the current period on its pages. Its historical file, read Oct. 25, 2026, keeps the past ones. Past periods do not change. These are the Commission's figures for homes without electric space heat.

The big jump came June 1, 2025, when ComEd's price went from 6.552¢ to 10.028¢. Ameren's summer price rose the same month, from 8.277¢ to 12.180¢. In the table's periods through spring 2026, both stayed above their 2024 levels.

1. Every monthComEd sets its monthly adjustment (PEA), so what you pay for supply moves even when the price to compare does not.
2. Each JanuaryThe transmission charge changes. The Commission says it usually changes once a year, in January.
3. May 31, 2027The current price to compare ends.
4. The day after the current price endsThe next price starts. Plug In Illinois posts it when it is set.

An offer that is already running does not change on these dates, if its price is fixed. That is the point of a fixed price, and also why a fixed price set today may look good or bad after June.