How to Read Your ComEd Bill
ComEd (Commonwealth Edison) delivers electricity across Chicago and northern Illinois no matter who supplies your actual power — Illinois is a deregulated market, so you can choose an Alternative Retail Electric Supplier (ARES) instead of ComEd's own supply rate. Your bill separates supply, delivery, and ComEd's fixed charges and taxes.
Who ComEd is on your bill
ComEd is the regulated utility that owns and maintains the poles, wires, and meters delivering electricity to Chicago and much of northern Illinois. Regardless of who supplies your electricity, ComEd is who reads your meter, restores power after an outage, and maintains the local grid — the delivery side of your bill doesn't change based on your supplier.
Supply vs. delivery charges
Illinois allows customers served by ComEd (along with Ameren Illinois and MidAmerican) to choose who supplies the energy portion of their electric service. That means a ComEd bill splits into a supply charge — the actual electricity, which you can buy from ComEd or from an Alternative Retail Electric Supplier (ARES) — and a delivery charge, ComEd's regulated fee for the infrastructure, which stays the same no matter your supplier.
The "Price to Compare" and shopping for supply
ComEd bills include a "Price to Compare" — ComEd's own default supply rate, published so you can weigh it against offers from ARES suppliers. If you haven't shopped, you're simply on ComEd's supply rate; switching to an ARES changes only your supply price, not your delivery service, reliability, or who to call in an outage.
Fixed charges and taxes
Below supply and delivery, ComEd bills typically include a customer charge that applies every billing period regardless of usage, plus riders for things like transmission cost recovery and applicable state and local taxes. Individually these tend to be smaller line items, but they add up, especially in a low-usage month.
Reading your usage and rate history
ComEd bills generally show your usage for the current period next to recent months or the same month a year prior — a fast way to check whether a bigger bill is driven by more usage (a hot or cold month) or by a rate change on the supply or delivery side. ComEd's online account portal offers more detailed usage history, including hourly data for customers on ComEd's dynamic pricing programs.
Why comparing rate classes matters
Like most utilities, ComEd bills residential and commercial accounts under different rate classes, which affects how usage is priced and whether a demand charge applies. If you've moved from a residential to a small-business account, or your usage pattern has shifted, it's worth double-checking that your rate class still matches how you actually use electricity — a mismatch can quietly inflate the delivery portion of your bill over time.
Frequently asked questions
What is an ARES on a ComEd bill?
ARES stands for Alternative Retail Electric Supplier — a competitive company licensed to sell you electricity supply in Illinois. If you've signed up with one, your ComEd bill will show its charges for supply separately from ComEd's own delivery charges.
What is the "Price to Compare" on my ComEd bill?
It's ComEd's own default supply rate, published specifically so you have a benchmark to compare against offers from Alternative Retail Electric Suppliers. If you haven't switched, this is the rate you're currently paying for supply.
Does ComEd still deliver my power if I switch suppliers?
Yes. ComEd remains responsible for delivery, meter reading, outage response, and overall service reliability regardless of which supplier you choose — switching only changes who supplies the electricity and what you pay for it.
See this on your own bill
Upload your ComEd bill and Certo reads it for you — a free bill health score, a plain-English breakdown, and whether your supply rate is competitive.
Want it tracked automatically every month?
Plus and Pro track bill history, flag rate hikes and unusual usage, and (on Pro) build a custom efficiency checklist and savings tracker — so you're not re-checking this by hand.