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Illinois Electricity Rates 2026: What's Coming This Summer (And How to Prepare)

Ryan Cook•April 4, 2026•Updated Apr 17, 2026

If your electric bill has felt heavier lately, you're not imagining it. Illinois electricity rates have climbed sharply since 2021 — and they're about to jump again.

This isn't a temporary blip. There are three structural forces pushing rates higher at the same time: a global energy crisis from the Iran conflict, massive data center construction across the state, and record-breaking wholesale capacity auction prices that directly set what you pay per kilowatt-hour.

Here's what's actually happening, what's coming in June, and what your options are.

Timeline showing Illinois electricity rate increases from 2021 through projected summer 2026

Where Rates Stand Right Now (April 2026)

Illinois has two major utilities, and both have seen dramatic increases:

ComEd (northern Illinois, Chicagoland):

Current supply rate: 10.8¢/kWh — up 47% from January 2025
All-in residential rate: approximately 17¢/kWh
The ICC approved a $243 million delivery rate hike effective January 2026
IRA credits of ~$13/month offset some costs through May — but expire before summer

Ameren Illinois (central and southern Illinois):

Current supply rate: 8.77¢/kWh (first 800 kWh)
All-in residential rate: approximately 15.5¢/kWh — up 94% since 2021
Summer all-in rates reach roughly 20¢/kWh (June through September)
The ICC approved a $48 million delivery rate increase for 2026

For context, both utilities were around 8¢/kWh all-in in 2021. That was just five years ago.

What's Driving the Increases

It's not one thing — it's three things happening simultaneously.

Infographic showing the three forces driving Illinois electricity rates higher

1. Capacity Auction Prices Exploded

This is the biggest single driver, and most people have never heard of it.

Your utility doesn't generate its own electricity. It buys power on wholesale markets run by regional grid operators — PJM for ComEd territory and MISO for Ameren territory. These operators run annual "capacity auctions" where power generators bid to supply electricity. The clearing price flows directly into your rate.

Those auctions have gone haywire:

Auction	Previous Price	Current Price	Increase
PJM (ComEd)	$28.92/MW-day	$329.17/MW-day	+1,038%
MISO Summer (Ameren)	$30/MW-day	$666.50/MW-day	+2,122%

These aren't typos. PJM capacity costs went up ten-fold in two years. MISO summer capacity went up twenty-two-fold in a single year.

There's no buffer between these auction prices and your bill. When the clearing price goes up, your rate goes up — typically at the next June reset.

2. Data Centers Are Eating the Grid

Illinois has approved 27 of 28 applications for tax-exempt data center status. Another 30+ facilities are planned. These aren't small buildings — a single large data center can consume 600 megawatts, roughly equivalent to powering an entire mid-size city.

Data centers now consume 5.43% of all Illinois electricity. PJM's Independent Market Monitor found that 70% — or $9.3 billion — of the capacity cost increase was driven by data center demand.

The Illinois Power Agency projects capacity shortfalls beginning in 2029 for northern Illinois and 2031 for southern Illinois. Governor Pritzker has proposed a two-year suspension of data center tax incentives starting July 2026 — but the facilities already approved aren't going away.

For a deeper dive on this, see our earlier analysis: Data Centers Drove 70% of Illinois's Capacity Cost Spike.

3. Global Energy Instability

The Iran conflict has sent oil to $112/barrel and disrupted 20% of global LNG supply. Illinois is somewhat insulated because 53% of our electricity comes from nuclear power — but the 17% that comes from natural gas is exposed to global price swings.

More importantly, the next utility procurement auctions will reflect a world where energy is more expensive everywhere. If the conflict isn't resolved before June, elevated gas futures will get baked into the rates you pay for the next 6-12 months.

What's Coming in June 2026

The June rate reset is when the 2026-2027 capacity auction prices take effect. Here's what to expect:

ComEd customers: CUB warns of another 20-25% increase on top of already elevated rates. The IRA credits that softened the blow ($13/month) expire before summer. Combined with the new capacity charge, summer bills could reach $180-220/month for a typical household.

Ameren customers: Summer supply rates historically jump from ~9¢ to ~12¢/kWh as seasonal capacity charges kick in. With the new MISO auction prices, the CUB warns summer bills could hit $200+/month for average homes.

Neither utility expects relief anytime soon. CUB's assessment: rates will stay elevated "for at least the next few years" due to structural demand growth from data centers and infrastructure investment.

How Illinois Compares to the Rest of the Country

Despite the increases, Illinois is still slightly below the national average — but the gap is closing fast.

Bar chart comparing Illinois electricity rates to neighboring states and the national average

State	Rate (Apr 2026)	Rank
Missouri	11.8¢/kWh	3rd cheapest
Iowa	12.8¢/kWh	8th cheapest
Indiana	16.2¢/kWh	31st
Illinois	16.4¢/kWh	32nd
Wisconsin	18.2¢/kWh	36th
National avg.	17.5¢/kWh	—

Source: Choose Energy, April 2026

Illinois went from well-below-average to essentially average in just a few years. And with summer rates pushing toward 20¢+, Illinois could land above the national average by July.

When Will Rates Come Back Down?

The honest answer: probably not for a while. Here's why:

Data center demand is structural — those facilities run 24/7 for decades. The 27 already approved aren't going away.
Grid infrastructure costs money — aging transmission lines, new capacity to meet demand, and reliability upgrades all get baked into delivery charges.
Capacity auctions look forward — even if gas prices stabilize, the auctions are pricing in tight supply margins through at least 2028.
The Iran conflict — if it persists, global energy costs stay elevated and trickle into US markets.

CUB and industry analysts broadly agree: expect elevated rates through at least 2028-2029, with the possibility of marginal relief if data center growth slows or new generation capacity comes online.

What You Can Do Right Now

You have three realistic options to control your electricity costs:

1. Solar — Lock in your rate for 15-25 years

Solar eliminates your exposure to all three forces pushing rates up. Once panels are on your roof, your energy cost is fixed — no auctions, no data center demand, no geopolitical risk.

Lease ($0 down): Fixed monthly payment for 15 years, typically lower than your current bill. Battery backup included.
Cash purchase: Own the system. Federal tax credit + Illinois SREC payments bring the payback to 8-10 years, then free power for 15+ more.
Solar for All: Income-qualified? The state installs solar at zero cost. No credit check.

2. Energy efficiency — Reduce your usage

This won't stop rate increases, but it reduces the volume they apply to:

Air-seal and insulate your attic (biggest bang for the buck)
Smart thermostat programming
LED lighting throughout
High-efficiency HVAC when it's time to replace

3. Alternative supply — Shop your rate

Illinois is a deregulated market. You can choose an alternative electricity supplier through the ICC's Plug In Illinois site. Fixed-rate plans can lock in your supply cost — but read the fine print on contract terms and cancellation fees.

The Bottom Line

Illinois electricity rates are up 47-94% since 2021. Another increase hits in June 2026. The forces driving it — data centers, capacity auctions, and global energy instability — aren't temporary.

You can wait and absorb each increase, or you can take control of your energy cost now. The incentives are still available, and the math gets better every time rates go up.

See what solar saves in your city →

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

Frequently Asked Questions

Illinois residential electricity rates average 15–17¢ per kWh all-in as of April 2026, with ComEd customers paying approximately 17¢/kWh and Ameren Illinois customers paying about 15.5¢/kWh. Summer rates in Ameren territory climb to roughly 20¢/kWh from June through September. Both utilities have seen dramatic increases since 2021 — Ameren Illinois rates are up 94% and ComEd rates are up 47% since January 2025 alone. The Illinois Commerce Commission approved a $243 million delivery rate hike for ComEd effective January 2026, plus a $48 million delivery increase for Ameren. Another rate adjustment takes effect in June 2026 when new capacity auction prices flow through. For specific per-city rates, see our Illinois rate tracker updated monthly with the latest ComEd and Ameren data.

ComEd's June 2026 rate increase reflects the record-breaking PJM capacity auction, where clearing prices rose from $28.92/MW-day to $329.17/MW-day — a 1,038% increase. Capacity costs flow directly into the supply portion of your bill at the June annual reset, which means most ComEd residential customers should expect a double-digit percentage jump in the supply rate starting with their June or July 2026 statement. The $13/month IRA rate-relief credit that offset some costs through May 2026 also expires right before the spike hits. A typical Chicagoland household using 750 kWh/month will likely see $15–$30 added to their monthly bill starting this summer. Our interactive rate tool tracks the exact per-utility rates as they update.

Ameren Illinois summer 2026 all-in rates are projected at approximately 20¢/kWh during the June-through-September summer period, driven by the MISO summer capacity auction that cleared at $666.50/MW-day — up 2,122% from the prior year's $30/MW-day. Ameren's baseline supply rate currently sits at 8.77¢/kWh for the first 800 kWh, but summer seasonal pricing layered with the new capacity costs pushes the all-in rate substantially higher. For a typical 1,000 kWh/month Central or Southern Illinois household, this works out to roughly $200/month summer bills compared to about $155/month in winter. Ameren territory has now seen a 94% rate increase since 2021, faster than any major Midwest utility, making it the hardest-hit region for electricity cost inflation.

Three structural forces are pushing Illinois electricity rates higher simultaneously. First, PJM and MISO wholesale capacity auctions have seen historic increases — PJM cleared at $329.17/MW-day (up 1,038%) and MISO summer at $666.50/MW-day (up 2,122%). Second, data center construction is consuming 5.43% of all Illinois electricity, and PJM's Independent Market Monitor attributed 70% — or $9.3 billion — of the capacity cost spike to data center demand. Illinois has approved 27 of 28 data center applications with another 30+ planned. Third, global energy instability from the Iran conflict has pushed LNG and natural gas prices higher, which affects the 17% of Illinois generation coming from natural gas. The Illinois Power Agency projects capacity shortfalls beginning in 2029 for northern Illinois and 2031 for southern Illinois, meaning rate pressure will continue.

Illinois electricity rates are not expected to decrease in the near-term, with most forecasts projecting continued increases through at least 2028. The Illinois Power Agency has flagged capacity shortfalls starting in 2029 for northern Illinois and 2031 for southern Illinois, which typically correlates with sustained upward rate pressure until new generation capacity comes online. Governor Pritzker has proposed a two-year suspension of data center tax incentives starting July 2026, which could slow new demand growth, but the 27 data centers already approved will continue consuming capacity. The most reliable ways to reduce your effective electricity cost are locking in a fixed lease rate with solar (typically around 10¢/kWh avg. for 15 years with battery), installing a solar system to offset grid purchases, or qualifying for Illinois Solar for All if income-eligible.

The most effective protection against rising Illinois electricity rates is locking in a fixed-rate solar lease or purchasing a solar system. A typical 15-year lease runs roughly 10¢/kWh average with a battery included, compared to 15–20¢/kWh and climbing on utility rates — the savings gap widens every year rates rise. For homeowners who don't qualify for solar or prefer not to install, strategies include: switching to an alternative retail electric supplier with a fixed-term contract, enrolling in ComEd's Residential Real-Time Pricing for load-shifting households, or qualifying for Illinois Solar for All if your household income is at or below 80% of Area Median Income. Energy efficiency upgrades — heat pumps, insulation, LED lighting — also reduce the kilowatt-hours your bill is exposed to at increasing rates.

The 2026 average residential electricity rate in Illinois is approximately 15–17¢/kWh all-in, depending on your utility territory and season. ComEd residential customers (northern Illinois, Chicagoland) average 17¢/kWh in 2026, with supply at roughly 10.8¢/kWh plus delivery and miscellaneous charges. Ameren Illinois residential customers (central and southern Illinois) average 15.5¢/kWh annually, rising to approximately 20¢/kWh during the June–September summer period. MidAmerican Energy customers in the Quad Cities area pay rates closer to 12–13¢/kWh. For context, Illinois was around 8¢/kWh statewide in 2021 — the current rate environment represents a roughly 90% increase in five years, with another June 2026 reset pushing rates higher still based on record PJM and MISO capacity auction results.