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Ameren vs ComEd 2026: Which Costs More Per kWh? (ComEd Runs ~1.5¢ Higher)

Ryan Cook•April 4, 2026•Updated Sep 13, 2026

If you live in Illinois, you're on one of two electric utilities: ComEd in the north or Ameren Illinois in the central and southern parts of the state. Both have raised rates dramatically since 2021, but they've done it differently — and one is consistently more expensive than the other depending on when you look.

Here's how they actually compare in 2026, broken down by every component that shows up on your bill.

Map showing ComEd territory in northern Illinois and Ameren territory in central and southern Illinois with current rates

ComEd vs Ameren: Which Costs More Per kWh?

In the non-summer months (the April 2026 figures below), ComEd is more expensive. But Ameren catches up — and sometimes passes ComEd — during summer months.

Updated September 13, 2026: the figures in this section are the April 2026 non-summer rates. The summer Price to Compare through September 30, 2026 is 11.326¢ for Ameren Illinois and 10.399¢ for ComEd, per the ICC's Plug In Illinois pages.

Component	ComEd	Ameren Illinois
Supply rate	10.8¢/kWh	8.8¢/kWh
Delivery charges	~6.5¢/kWh	~4.6¢/kWh
Monthly customer charge	$15.50	$14.51
All-in rate (non-summer)	~17¢/kWh	~15.5¢/kWh
All-in rate (summer)	~21¢/kWh	~20¢/kWh
Increase since 2021	+113%	+94%

ComEd runs about 1.5¢/kWh higher than Ameren during non-summer months. That gap narrows in summer when Ameren's delivery rates jump sharply.

How Your Bill Is Built

Most people look at one number — the total on the bill. But your rate is actually made up of several components, and ComEd and Ameren structure them differently.

Stacked bar chart breaking down the components of a ComEd vs Ameren bill

Supply Charges (what the electricity itself costs)

This is the "Price to Compare" — the part you can theoretically shop for with an alternative supplier.

ComEd (April 2026): 10.819¢/kWh

Electric supply: 7.841¢/kWh
Transmission: 1.819¢/kWh
Purchased electricity adjustment: +1.159¢/kWh (changes monthly)

Ameren (April 2026): 8.769¢/kWh (first 800 kWh)

Electric supply: 5.927¢/kWh
Transmission: 2.629¢/kWh
Supply cost adjustment: 0.312¢/kWh

ComEd's supply rate is 2¢/kWh higher than Ameren's. The main reason: ComEd is in PJM territory, where capacity auction prices have been higher than MISO (Ameren's grid operator). The June reset that pushed ComEd's summer Price to Compare to 10.399¢ is covered in full in our ComEd rate increase 2026 breakdown. PJM's 2026-2027 capacity price cleared at $329/MW-day, while MISO's annual average was around $217/MW-day.

Delivery Charges (what the poles and wires cost)

This is the non-shoppable part — you pay it regardless of who supplies your electricity.

ComEd:

Customer charge: $15.50/month
Distribution: 6.333¢/kWh (Distribution Facilities Charge, beginning with April 2026 bills) plus a 0.128¢/kWh distribution tax
Metering: $3.87/month (standard meter)

Ameren:

Customer charge: $8.55/month
Meter charge: $5.96/month
Distribution (non-summer): 4.572¢/kWh (first 800 kWh)
Distribution (summer): 7.811¢/kWh — jumps 71% in June

This is where Ameren's summer spike comes from. Their delivery rate nearly doubles between May and June. ComEd's delivery rate stays relatively flat year-round.

The Summer Flip

During non-summer months (October-May), ComEd is clearly more expensive. But starting in June, Ameren's delivery charges spike and the gap almost disappears:

Season	ComEd All-In	Ameren All-In	Difference
Winter (Jan-May)	~17¢/kWh	~15.5¢/kWh	ComEd +1.5¢
Summer (Jun-Sep)	~21¢/kWh	~20¢/kWh	ComEd +1¢
Peak summer day	~23¢/kWh	~22¢/kWh	Nearly even

In the hottest months, when air conditioning drives usage to 1,200+ kWh, total bills land in the same ballpark — $200-260/month for both utilities.

Why Both Utilities Cost So Much More Than in 2021

Five years ago, both utilities charged around 8¢/kWh all-in. The increases come from different sources but hit at the same time:

Capacity costs — the wholesale price of guaranteeing enough power plants exist to meet peak demand. PJM capacity rose 1,038% in two years. MISO summer capacity rose 2,122% in one year. These costs flow directly into supply rates.

Data centers — Illinois approved 27 data centers that collectively consume 5.43% of statewide electricity. PJM's market monitor attributed 70% ($9.3 billion) of capacity cost increases to data center demand.

Infrastructure investment — both utilities won ICC approval for delivery rate hikes: $243 million for ComEd, $48 million for Ameren. Grid upgrades, aging equipment replacement, and storm hardening all cost money.

Global energy — the Iran conflict has pushed oil to $112/barrel and disrupted global LNG. While Illinois is 53% nuclear (good insulation), the 17% natural gas component still feels the pressure.

What About Alternative Suppliers?

Illinois is a deregulated electricity market. You can choose a different supplier for the "supply" portion of your bill through Plug In Illinois. The delivery charges stay the same regardless.

Should you switch? It depends:

Fixed-rate plans can lock in your supply cost below the current Price to Compare — useful if you expect rates to keep rising
But — read the fine print. Many alternative suppliers charge early termination fees, have variable-rate periods after the fixed term, or include hidden charges
CUB recommends comparing carefully and watching for introductory teaser rates that spike after 3-6 months

The supply portion is typically 55-65% of your total bill. Even if you find a great alternative supplier, you're only shopping that portion — delivery charges stay fixed.

The Solar Equation: How It Changes by Utility

Solar economics actually differ meaningfully between ComEd and Ameren territory:

Factor	ComEd Territory	Ameren Territory
Rate you're offsetting	~17-21¢/kWh	~15.5-20¢/kWh
Grid operator	PJM	MISO
Net metering	Supply-rate credit (~6-8¢/kWh)	Supply-rate credit (~6-8¢/kWh)
SREC value	Same statewide	Same statewide
Avg. sun hours	4.0-4.2/day	4.3-4.7/day
Solar payback	Faster (higher rate)	Slightly longer
25-year savings	Higher (higher rate)	Still substantial

ComEd customers actually benefit more from solar in dollar terms because they're offsetting a higher per-kWh rate. But Ameren territory gets slightly more sunshine, which partially compensates.

Either way, both utilities are now expensive enough that solar pays for itself well within the system's lifespan. The question isn't whether solar makes financial sense — it's which option fits your situation:

$0 down lease — predictable payment, battery included, maintenance covered
Cash purchase — own the system and maximize savings with Illinois Shines RECs
Solar for All — income-qualified? Zero cost to you

The Bottom Line

ComEd is more expensive than Ameren by about 1.5¢/kWh in non-summer months. That gap narrows in summer. Both utilities have raised rates dramatically since 2021, and neither expects to come back down anytime soon.

The underlying forces — data center demand, capacity auction prices, infrastructure costs, and now global energy instability — are structural, not cyclical. Your bill trajectory is clear: up.

Solar gives you a way off that escalator. Whether you're in Chicago or Springfield, Naperville or Belleville, the math works.

Check your city's solar savings →

Sources

Ryan Cook is the founder of Ltd Solar Consulting, helping Illinois homeowners across both ComEd and Ameren territory. Get a free quote or call (618) 217-2001.

Frequently Asked Questions

ComEd is more expensive than Ameren Illinois in most of the year, averaging about 17¢/kWh all-in during non-summer months compared to Ameren's 15.5¢/kWh — a difference of roughly 1.5¢/kWh. However, the gap narrows during the summer months (June through September) when Ameren's delivery rates spike by approximately 71%, pushing Ameren's all-in summer rate to about 20¢/kWh versus ComEd's 21¢/kWh. On the hottest peak-demand days, both utilities can reach 22-23¢/kWh, making total monthly bills nearly identical in the $200-260 range for typical summer usage of 1,200+ kWh. Since 2021, ComEd rates have risen 113% while Ameren has risen 94%, so ComEd's relative increase has been sharper even though both utilities are now dramatically more expensive than they were five years ago.

On affordability, Ameren Illinois is generally the cheaper utility for most of the year, though neither is affordable by historical standards. Non-summer residential rates favor Ameren customers by about 1.5¢/kWh — a monthly savings of roughly $15 on 1,000 kWh of usage compared to ComEd. The difference comes mainly from grid operator costs: ComEd sits in PJM territory where capacity auctions cleared at $329/MW-day, while Ameren is in MISO territory at roughly $217/MW-day annual average. Ameren also has lower delivery charges ($8.55 customer charge vs. $15.50 for ComEd) during non-summer months. During summer, however, Ameren's seasonal delivery rate spike pushes costs to nearly match ComEd. Both utilities have seen 90%+ rate increases since 2021, making Illinois one of the fastest-rising electricity markets in the Midwest regardless of territory.

ComEd's residential delivery charge in 2026 is 6.333¢/kWh for the Distribution Facilities Charge (single-family, no electric heat) plus a 0.128¢/kWh Illinois Electricity Distribution Tax charge — about 6.46¢/kWh — beginning with April 2026 bills, plus a fixed monthly customer charge of $15.50 and a standard metering charge of $3.87 per month. Delivery charges are the non-shoppable portion of the bill, covering the poles, wires, transformers, and grid maintenance that get electricity from power plants to your home. ComEd's delivery rate increased in January 2026 after the Illinois Commerce Commission approved a $243 million delivery rate hike. For a typical Chicagoland household using 750 kWh per month, delivery charges alone total approximately $68 per month before supply costs are added. Unlike Ameren, ComEd's delivery rate stays relatively flat year-round rather than spiking seasonally — which is why ComEd is consistently more expensive in non-summer months.

Ameren Illinois residential customers pay approximately 15.5¢/kWh all-in during non-summer months and roughly 20¢/kWh during the summer period from June through September. The non-summer 2026 supply rate (Price to Compare) was 8.769¢/kWh for the first 800 kWh, which included 5.927¢/kWh for electric supply, 2.629¢/kWh for transmission, and a 0.312¢/kWh supply cost adjustment; the summer rate is 11.326¢/kWh through September 30, 2026. Delivery charges are 4.572¢/kWh in non-summer months but jump to 7.811¢/kWh in summer — a 71% increase. Ameren's fixed monthly charges total about $14.51 ($8.55 customer charge plus $5.96 meter charge). Rates have risen 94% since 2021 when Ameren was around 8¢/kWh all-in. The January 2026 $48 million delivery rate hike approved by the Illinois Commerce Commission adds further pressure, and MISO summer capacity costs cleared at $666.50/MW-day for 2026.

Electricity in ComEd territory is relatively expensive compared to both other Illinois utilities and many peer Midwest utility service areas. ComEd's all-in residential rate of approximately 17¢/kWh exceeds Ameren Illinois (15.5¢/kWh), MidAmerican Energy in the Quad Cities (12-13¢/kWh), and several major Midwest investor-owned utilities such as DTE Energy in Michigan (approximately 18¢/kWh but with different rate structures) and Duke Energy Indiana (around 14¢/kWh). ComEd has risen 113% since 2021 — faster than most peer utilities. The main driver is PJM capacity auction pricing, which cleared at $329/MW-day for 2026-2027, combined with heavy data center demand in the ComEd service territory that has consumed significant grid capacity. The Citizens Utility Board projects ComEd rates will remain elevated through at least 2028 due to these structural pressures.

ComEd costs more than Ameren during winter primarily because of higher supply costs from PJM's capacity market and higher distribution charges on ComEd's delivery side. In April 2026, ComEd's supply rate was 10.819¢/kWh compared to Ameren's 8.769¢/kWh — a 2¢/kWh difference driven mainly by PJM capacity prices clearing at $329/MW-day versus MISO at approximately $217/MW-day annual average. On the delivery side, ComEd charges $15.50 per month customer fee plus 6.333¢/kWh distribution (plus a 0.128¢/kWh distribution tax), while Ameren charges a combined $14.51 in fixed monthly fees plus only 4.572¢/kWh distribution during non-summer months. The result is roughly a 1.5¢/kWh all-in advantage for Ameren customers from October through May. However, Ameren's delivery rate jumps 71% in summer, which nearly erases the winter advantage during the June-through-September cooling season.