Published on December 18, 2025 3:55 pm
Last Updated on December 18, 2025 3:55 pm
The Illinois Commerce Commission (ICC) struck $11.2 million from Ameren Illinois’ $59.6 million multi-year rate reconciliation request. The decision is the first in a new performance-based evaluation process designed to reconcile actual utility spending with the approved investments outlined in the utility’s multi-year grid and rate plans.
“The ICC’s responsibility is to balance the interests of Illinois’ utilities and their consumers, and our new grid planning process is designed to hold the state’s largest electric utilities accountable for their performance,” said ICC Chairman Doug Scott. “The ICC’s decision today reiterates that unsupported departures from Ameren’s approved grid plan are inconsistent with the goals of the grid planning process, and it is the utility’s responsibility to prove that any adjustments made are reasonable and prudent for maintaining our power system.”
The decision requires Ameren to include affordability data updates and cost benefit analyses of related grid plan projects in future rate reconciliation dockets to allow the ICC and relevant stakeholders to evaluate the impact of Ameren’s grid plan in real time.
In 2024, the ICC approved Ameren’s revised grid plan to strengthen power grid reliability, support progress toward Illinois’ clean energy goals, and hold Ameren accountable for meeting the performance metrics set by the Commission. In addition to the electric grid plan requirement, the Climate and Equitable Jobs Act (CEJA) subjects Ameren and ComEd to performance-based evaluations in place of a preapproved formula rates.
The ICC issued its decision after reviewing Ameren’s reconciliation filing, along with materials submitted by the utility, ICC staff, and various intervenors over the course of an eight-month legal proceeding. In accordance with the Public Utilities Act, proposed costs are recoverable only when the utility demonstrates they are reasonable and prudent. In addition to traditional standards under the Public Utilities Act, the ICC evaluated Ameren’s actual costs using the cost-effectiveness, coordinated long term planning, equity, affordability, and transparency considerations outlined in CEJA.
The impact of the decision on individual customers will vary based on service class and energy usage.
Ameren Illinois serves 1.2 million electric customers in central and southern Illinois. More information regarding Ameren’s annual reconciliation can be found in Docket No. 25-0382.
