The last lines on a ComEd bill are taxes, and they are the only lines printed without a rate. A home bill prints State Tax. A business bill prints State Electricity Excise Tax and, in most towns, Municipal Utility Tax. On the home bill used throughout this site, 1,518 kilowatt hours, the State Tax was $5.01 and the bill did not say how it got there.
This page has the filed rates, shows the $5.01 reproduced from them to the cent, and says plainly which parts of these two lines cannot be checked from the bill alone.
Three names, two taxes
ComEd's tariff collects both under one rider, Rider TAX, Municipal and State Tax Additions, applicable to every rate ComEd offers except the two that serve retail electric suppliers and metering service providers rather than customers.
State Tax and State Electricity Excise Tax are the same line. Rider TAX says the state tax additions are separately stated on the monthly bill of each retail customer, and ComEd's residential layout shortens the name while its commercial layout spells it out. The tax is the Illinois electricity excise tax, which the rider describes as an excise tax on the privilege of using electricity purchased for use or consumption and not for resale, imposed under the Electricity Excise Tax Law, 35 ILCS 640/2-4.
Municipal Utility Tax is a separate tax that exists only where a municipality has adopted an ordinance imposing it, under Section 8-11-2 of the Illinois Municipal Code. Rider TAX says it is stated on the bill with the designation Municipal Tax or City Tax or a similar legend, which is why the printed name varies. ComEd collects it and passes it to the municipality.
Both are charged on kilowatt hours delivered, so both apply whoever supplies your energy.
The state tax, tier by tier
Rider TAX files the state tax as ten rates, each applied to a slice of the month's kilowatt hours in order. These are the filed rates on 1st Revised Sheet No. 258, effective November 5, 2021, and ComEd's 2026 filing index through August shows no revision to that sheet since.
| Kilowatt hours in the month |
Rate (cents per kWh) |
| The first 2,000 |
0.330 |
| The next 48,000 |
0.319 |
| The next 50,000 |
0.303 |
| The next 400,000 |
0.297 |
| The next 500,000 |
0.286 |
| The next 2,000,000 |
0.270 |
| The next 2,000,000 |
0.254 |
| The next 5,000,000 |
0.233 |
| The next 10,000,000 |
0.207 |
| All over 20,000,000 |
0.202 |
Almost every home lands entirely in the first tier. A household would need to use more than 2,000 kilowatt hours in a month, which the reference home did in five of the thirteen months on its usage graph, before the second rate touched a single unit. A business at 18,000 kilowatt hours reaches the second tier and no further.
Rider TAX also names who is not charged: business enterprises exempted under Section 2-4(c) of the Excise Tax Law, and self-assessing purchasers, who pay the state directly instead of through the utility.
Checked against a real bill
The reference bill is a home at 1,518 kilowatt hours, May 1 to June 2, 2026. It printed State Tax $5.01 and no rate.
| Step |
Figure |
| Kilowatt hours, all inside the first tier |
1,518 |
| Times the filed first-tier rate |
0.330 cents per kWh |
| Result |
$5.0094, printed $5.01 |
It reconciles to the cent from the filed tier. Dividing the other way, $5.01 over 1,518 kilowatt hours is 0.330 cents, the first-tier rate exactly, which is how the bill's own arithmetic confirms which tier it was in.
A worked example for a business, from the filed tiers
This is arithmetic on the filed rates, not a bill. A business using 18,000 kilowatt hours in a month, with no exemption:
| Slice |
Kilowatt hours |
Rate |
Amount |
| First tier |
2,000 |
0.330 cents |
$6.60 |
| Second tier |
16,000 |
0.319 cents |
$51.04 |
| State Electricity Excise Tax |
18,000 |
|
$57.64 |
The tiers step down slowly, so the tax is close to proportional to usage for any account under 50,000 kilowatt hours: 0.320 cents per kilowatt hour on average here, against 0.330 on the first 2,000.
The municipal tax, a rate each municipality sets
The municipal tax uses the same ten kilowatt hour categories, labelled A to J on the filed sheets, but the rate in each category is set by the municipality's ordinance, not by the state or by ComEd. Rider TAX lists them town by town, and the list changes as towns adopt or amend ordinances: ComEd filed a revised sheet for Campton Hills effective January 1, 2026 and for Lake Forest effective March 1, 2026.
Every filed municipal rate includes an addition equal to three percent of the tax, which the Municipal Code allows the utility to keep as reimbursement for administering the collection. The rates on the sheet are the rates on the bill, three percent included.
A few rows from the filed table, in cents per kilowatt hour:
| Municipality |
First 2,000 kWh (A) |
Next 48,000 kWh (B) |
Next 50,000 kWh (C) |
| Chicago |
0.628 |
0.412 |
0.371 |
| Aurora |
0.628 |
0.412 |
0.371 |
| Arlington Heights |
0.628 |
0.412 |
0.371 |
| Berwyn |
0.610 |
0.400 |
0.359 |
| Barrington |
0.572 |
0.375 |
0.337 |
| Amboy |
0.333 |
0.218 |
0.197 |
Most of the larger towns sit at the same figures as Chicago; smaller ones are lower, and some are below half of it. In the first tier the municipal tax at the Chicago rate is nearly twice the state tax, which makes it the larger of the two tax lines on a business bill in most of ComEd's territory. On 18,000 kilowatt hours at the Chicago rates, the same arithmetic as above gives $12.56 on the first 2,000 and $65.92 on the next 16,000, $78.48 in all.
Where there is no ordinance, there is no line. The reference home bill above prints no municipal tax at all, which is what a service address outside a taxing municipality produces.
What the bill alone cannot tell you
Three things, and this page will not fill them in with a guess.
The rate. Neither tax line prints one. The state tax can be recovered by dividing, as above, but only because the tiers are filed; the bill itself gives you a dollar amount and nothing else.
The municipality. The municipal line does not name the town whose ordinance set it. The service address on the bill usually settles it, but an address near a boundary, or an unincorporated one, does not, and the filed rate for the town is the only way to check the line.
Whether an exemption applied. The excise tax exclusions for certain business enterprises and self-assessing purchasers are a matter of the account's status with the state, not anything printed on the bill. A business bill whose state tax is lower than the tiers produce is either exempt in part or in error, and the bill cannot say which.
The free bill reader re-adds these lines into the printed total, which is how it confirms they were read correctly, and it reports them as read from the bill rather than reconciled to the tariff, because of exactly the three gaps above.
Can they be avoided?
Not by anything a household or an ordinary business can elect. Both taxes are charged on kilowatt hours delivered, so switching to a retail electric supplier does not touch them. Using less electricity reduces them in proportion, at about a third of a cent per kilowatt hour for the state and around two thirds of a cent for the municipality at the Chicago rate. The statutory exemptions are for specific enterprise categories and for purchasers who assess the tax themselves, and they are claimed with the state, not on the bill.
What this page was checked against
The state tiers, the statutory citations, the exclusions and the municipal mechanics are quoted from Rider TAX in ComEd's filed Schedule of Rates, Sheet No. 258 and the municipal rate sheets that follow it. The 2026 filing index was read to confirm which of those sheets have been revised since. The printed $5.01 is from one real home bill and the filed first-tier rate reproduces it to the cent. No business bill with a real tax line has been reconciled here, and the business figures on this page are arithmetic on the filed tiers, labelled as such.
The other per kilowatt hour line the bill prints in the delivery section, also uniform and also unavoidable, is the IL Electricity Distribution Charge. The rider block above the taxes is in every line on a ComEd bill, explained, and the Customer Charge covers the fixed lines that do not move with usage at all.
