On a ComEd commercial account, the demand charge does not appear on the bill under that name. It appears as the Distribution Facilities Charge, on the delivery side of the bill. It follows the general demand-charge mechanism, but ComEd applies a specific set of rules that decide exactly which moment of the month sets it.
It is billed on demand, not on energy
The Distribution Facilities Charge is not billing the energy you used over the month. It is billing the highest rate at which you drew power, your peak demand, measured in kilowatts over a thirty minute interval. A site can use a modest amount of total energy and still carry a large Distribution Facilities Charge, because the two numbers measure different things.
Two rules decide which interval counts
First, ComEd measures billed demand as the highest thirty minute demand recorded inside the on-peak window: nine in the morning to six in the evening, Monday through Friday, excluding holidays. Power drawn outside that window does not set the charge, no matter how high it climbs. A spike at eight thirty in the morning, thirty minutes before the window opens, can be the highest reading of the day and still set nothing.
Second, the charge is a flat rate per kilowatt of that billed demand. There is no separate off-peak demand charge, and on the standard commercial delivery classes there is no ratchet carrying a past peak forward. One qualifying interval, priced once, for the month.
What the rate has looked like
The per kilowatt rate depends on the delivery class and the year. Reconstructed from real reconciled ComEd bills, to the cent:
- A Small Load account (under 100 kW) on a 2025 bill: about $14.59 per kW. A 40.91 kW peak produced a $596.88 Distribution Facilities Charge.
- A Medium Load account (100 to 400 kW) on a 2025 bill: about $14.92 per kW. A 242.57 kW peak produced a $3,619.14 charge.
- A Retail Delivery Service account on a 2026 bill: about $12.93 per kW under the newer bill format. A 46.20 kW peak produced a $597.37 charge.
The rate itself is rarely the surprise. The surprise is that a single interval, often half an hour long, sets a line that can rival the entire energy cost for the month, and the bill shows only the result, never the interval that produced it.
Find the interval that set yours
The bill gives you the Distribution Facilities Charge as a finished number. The interval data behind it holds the thirty minutes that actually set it. You can reconstruct that on your own ComEd bill, reconciled to the cent, with the free demand charge tool. We do not sell energy and we take no commission. The tool exists to make the charge legible, nothing more.