Ameren Illinois set its summer electricity supply price at 11.326 cents per kilowatt-hour for the June 1 through September 30 period, a rate that takes effect immediately and will appear on bills this season.
The number matters: the new summer supply rate is about 39% higher than Ameren's summer price two years ago, and the Citizens Utility Board cautions that switching to an alternative electricity supplier is not an automatic path to savings. Illinois consumers have lost roughly $2 billion to alternative suppliers since 2015, CUB estimates, and the watchdog says many promotional offers carry traps that can make a switch costlier.
Market pressures behind the increase are straightforward. Rising electricity demand — including load from new and proposed data centers — is pushing wholesale prices higher, and alternative suppliers operate inside that same market. That means a supplier advertising a low introductory rate today is buying power in the same, higher-priced market as Ameren.
The conflict for customers is simple and immediate: Ameren's supply price is up, but CUB says the alternative supplier market is full of teaser rates, additional monthly fees, and contract terms that can drive bills above the utility's supply charge. Some offers start low and then reset; others add monthly charges or automatic renewals that lock customers into higher costs.
Sarah Moskowitz of the Citizens Utility Board urged consumers to read offers carefully, noting that customers have already lost far too much money to alternative suppliers over the last decade and that, even in a high-priced market, Ameren may still be the safer option for many households. Moskowitz's point underscores the practical problem: precise savings or losses depend on the specific supplier contract a customer signs and on how long the introductory terms last.
Practical steps for customers deciding now are clear. Compare any alternative offer line by line with Ameren's 11.326-cent supply rate for the summer period; factor in all monthly fees and the post‑introductory rate; check the length and renewal terms of the contract; and avoid giving account numbers or a utility bill to door-to-door canvassers to prevent unauthorized switching known as slamming.
Remember, an alternative supplier affects only the supply portion of the bill; it does not shield a customer from future delivery or distribution rate increases set by the utility. CUB also recommends common-sense measures to reduce bills regardless of supplier choice: energy efficiency upgrades, enrollment in available payment assistance programs, and cautious, documented comparisons of offers before signing.
The next rate change that matters is months away: Ameren's supply price for the October 2026 through May 2027 period is expected to decrease, but that rate has not been finalized. That timing sharpens the unresolved question for consumers: whether switching now will save money through the summer window or cost more when teaser periods expire or fees and contract terms kick in. Because outcomes vary by offer and household usage, CUB and the new summer figure together leave a narrow and concrete decision for customers to make this week.
