10-K 0001002910-26-000009 (2026-02-18) vs 10-K 0001002910-25-000055 (2025-02-18)
| Section | Compared text | Words now | Changed |
|---|
| Risk Factors | Item 1A | 9,008 |
14.8% |
| MD&A | Item 7 | 23,262 |
35.4% |
| Legal Proceedings | Item 3, via Note 14 – COMMITMENTS AND CONTINGENCIES | 2,298 |
34.6% |
| Accounting Policies | Item 8, Note 1 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES | 4,199 |
15.9% |
The redline: what was cut and what was added
In each section, the paragraph that changed most, marked against last year's 10-K:
cut words struck through, new words highlighted and underlined.
MD&A 415 words changed in this paragraph; it is 36% similar to last year's version.
Net income attributable to Ameren common shareholders was $1,456 million, or $5.35 per diluted share, for 2025, and $1,182 million, or $4.42 per diluted share, for 2024, and $1,152 million, or $4.38 per diluted share, for 2023. 2024. Net income was favorably affected in 2024, 2025, compared with 2023, by increased infrastructure investments at Ameren Transmission and Ameren Missouri. Net income was also favorably affected in 2024, compared with 2023, by increased base rate revenues at Ameren Missouri effective June 1, 2025, pursuant to the MoPSC's June 2023 April 2025 MoPSC electric rate order as well as higher base rate revenues pursuant to the ICC's November 2023 natural gas rate order, which increased earnings and decreased tax expense at Ameren Transmission, Ameren Illinois Electric Distribution and Ameren Illinois Natural Gas. Additionally, earnings in 2024, compared with 2023, Gas due to the revaluation of excess deferred income tax regulatory liabilities. Earnings were also favorably affected by increased retail electric sales volumes at Ameren Missouri, primarily due to warmer July temperatures and colder winter temperatures in 2025, and by decreased other operations and maintenance expenses not subject to formula rates, riders, or trackers, largely because of lower energy center maintenance costs, lower storm costs, disciplined cost management including lower labor costs from decreased headcount and decreased use of contractors, and lower amortization of refueling costs for the Callaway Energy Center, partially offset by the absence in 2025 of the regulatory deferrals associated with the June 2023 MoPSC rate order. Net income in 2024, compared with 2023, was also favorably affected by increased retail electric sales volumes at an Ameren Missouri, primarily due to higher sales excluding customer energy-efficiency programs. Net income was unfavorably affected in 2024, compared with 2023, by two charges Missouri charge related to matters that originated over a decade ago. The first the resolution of these charges was recorded by Ameren Missouri related to an order from the United States District Court for the Eastern District of Missouri, which resolved all outstanding claims in the NSR and Clean Air Act litigation related to associated with the Rush Island Energy Center. The second charge was recognized Additionally, earnings were favorably affected by the increased deferral of financing costs related to rate base investments at Ameren Missouri and by increased infrastructure investments at Ameren Transmission and Ameren Illinois and ATXI for the decrease in the allowed base ROE under the MISO tariff resulting from the October 2024 FERC order, which included customer refunds for certain historical periods. Electric Distribution. Net income was unfavorably affected in 2024, 2025 compared with 2023, was also unfavorably affected 2024 by increased financing costs due to costs, primarily resulting from higher long-term interest rates on higher debt balances and interest rates at Ameren Missouri and Ameren (parent), (parent) and by increased other operations and maintenance expenses not subject to formula rates, riders, or trackers, excluding a lower recognized ROE under charge related to the MYRP, NSR and Clean Air Act litigation, primarily due to higher vegetation management costs, higher storm costs, and higher energy center maintenance expenses. Additionally, earnings were unfavorably affected by an increase in the weighted-average basic common shares outstanding, which reduced earnings per diluted share.
Source: Item 7, 10-K 0001002910-26-000009 vs Item 7, 10-K 0001002910-25-000055
Legal Proceedings 347 words changed in this paragraph; it is 35% similar to last year's version.
Federal and state laws, including the CSAPR, regulate emissions of SO2 and NOx through the reduction of emissions at their source and the use and retirement of emission allowances. allowances available for state budgets. In April 2022, the EPA proposed the Good Neighbor Rule of the Clean Air Act, which includes additional NOx emission reductions from power plants in Missouri, Illinois, and other states through revisions to the CSAPR. In January 2023, the EPA issued its final disapproval of Missouri’s proposed state implementation plan for addressing reduce the transport of ozone under from power plants by reducing the amount of CSAPR NOx allowances available for compliance. The EPA subsequently rejected state implementation plans proposed by Missouri and other states to comply with the Good Neighbor Rule of the Clean Air Act. The disapproval of the state plan allowed the EPA to implement revisions to the CSAPR through and issued a federal implementation plan that reduced the amount of NOx allowances available plan. The disapprovals for state budgets and imposed NOx emission limits on electric generating units for Missouri, Illinois, and other states under the Good Neighbor Rule of the Clean Air Act. In April 2023, the Missouri Attorney General and Ameren Missouri separately filed lawsuits in the United States Court of Appeals for the Eighth Circuit challenging the EPA’s disapproval of the Missouri state plan. Ameren expected a decision on Missouri’s proposed state implementation plan under the Good Neighbor Rule by the United States Court of Appeals for the Eighth Circuit in 2025, but, in February 2025, the EPA requested that the appellate court suspend the case indefinitely and indicated it was reviewing the basis for the disapproval of the some state implementation plans, including Missouri’s. Missouri’s, were stayed by multiple appellate courts, and in 2024, the United States Supreme Court issued a stay of the federal implementation plan. In January 2026, the EPA issued a proposed rule to reconsider the Good Neighbor Rule. Ameren Missouri complies with the current CSAPR requirements by minimizing emissions through the use of with low-sulfur coal, operation of two scrubbers at its Sioux Energy Center, and optimization of existing NOx air pollution control equipment. Reducing If a final rule is issued similar to the amount of state budget proposed rule, Ameren Missouri would not expect additional NOx allowances for compliance with NOx emission limits under the Good Neighbor Rule could result in additional controls being required on Ameren Missouri’s generating units and/or the reduction of operations. Any costs for compliance are expected at its coal-fired energy centers to be recovered from customers, subject to MoPSC prudence review, through the FAC or higher base rates. necessary.
Source: Item 3, via Note 14 – COMMITMENTS AND CONTINGENCIES, 10-K 0001002910-26-000009 vs Item 3, via Note 14 – COMMITMENTS AND CONTINGENCIES, 10-K 0001002910-25-000055
Risk Factors 263 words changed in this paragraph; it is 42% similar to last year's version.
The Ameren Companies have historically experienced minimal growth in energy demand for the past two decades. Recent However, current industry projections reflect the potential for significant growth in energy demand over the next decade, primarily arising from data centers to support artificial intelligence and further augmented by onshoring and electrification of manufacturing and an increase in transportation electrification. In addition, in February 2026, Ameren Missouri executed electric service agreements with large load customers under its large load customer rate plan, representing 2.2 gigawatts of demand. The Ameren Companies may or may not experience the energy demand growth currently being forecasted depending on the decisions of potential new customers about whether to locate their operations within our service territories. If new territories or whether customers elect to locate that have signed electric service agreements begin operations within our service territories, the Ameren Companies may not be able to provide the necessary electric service within the time periods required by those customers. The Ameren Companies may need to accelerate new generation build within current plans, and construct or obtain new generation sources and expand transmission and distribution facilities that are not currently within their plans. The Ameren Companies may not be able to plan, receive regulatory approvals, and execute those plans in a timely manner. Future expected timeframes. Also, demand from these customers growth may not be realized at the current projected pace as a result rate, or in the amount, expected if construction of customer facilities is not completed within expected timeframes, which is dependent on the ability of suppliers, contractors, and developers to meet contractual commitments and timely complete projects. In addition, expected demand growth may not be realized if emerging technologies are not broadly adopted at the rate expected, increased efficiency efficiencies in computing, and computing or other advances in these new customers may be transitory and exit our service territory. Significant uncertainty exists regarding future increases in technologies reduce energy demand within the Ameren Companies’ service territory, and whether and how the Ameren Companies will construct for data centers, or obtain the assets necessary to timely serve that additional demand. large load customers, such as data centers,
Source: Item 1A, 10-K 0001002910-26-000009 vs Item 1A, 10-K 0001002910-25-000055
Accounting Policies 127 words changed in this paragraph; it is 40% similar to last year's version.
We expect that regulators will reduce future revenues for deferred tax liabilities that were initially recorded at rates in excess of the current statutory rate. Therefore, reductions in certain excess deferred tax liabilities that were recorded because of decreases in the statutory rate have been credited to a regulatory liability. A regulatory asset has been established to recognize the probable recovery through future customer rates of tax benefits related to the equity component of allowance for funds used during construction, as well as the effects of tax rate increases. To the extent deferred tax balances are included in rate base, the revaluation of deferred taxes caused by a change in the statutory rate is recorded as a regulatory asset or liability on the balance sheet and will be collected from, or refunded to, customers. For deferred tax balances not included in rate base, the revaluation of deferred taxes caused by a change in the statutory rate is recorded as an adjustment to income tax expense on the income statement.
Source: Item 8, Note 1 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, 10-K 0001002910-26-000009 vs Item 8, Note 1 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, 10-K 0001002910-25-000055
Every change, by type
Sentences and paragraphs of AEE's Risk Factors and MD&A, 10-K 2026-02-18 against 10-K 2025-02-18.
Each links to the text at sec.gov.
Quiet changes are sentences kept from last year with one to four words changed, at least one of them a hedge, a modal or a qualifier
(may, could, will, not, significant, material…). A year or date rolling forward is not counted.
The full word list
adverse, adversely, all, although, anticipate, anticipates, any, approximately, believe, believes, can, cannot, certain, could, expect, expects, generally, however, if, intend, intends, largely, likely, many, material, materially, may, might, most, must, never, no, not, possible, primarily, probable, should, significant, significantly, some, substantial, substantially, unlikely, will, would
AddedRisk Factors
charge for our services. From time to time, our regulators may approve riders or other recovery mechanisms that allow electric or natural gas rates to be adjusted without a traditional regulatory rate review. These mechanisms could be changed or terminated.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedRisk Factors
•increased regulatory scrutiny and oversight resulting from more frequent outages;
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedRisk Factors
Realized energy demand from current and potential new customers may differ significantly from forecasts.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedRisk Factors
are not supported by local communities or do not receive necessary approvals by local municipalities. Although customers subject to the large load customer rate plan in Ameren Missouri’s service territory are required to sign agreements for specific term lengths to reasonably ensure rates they are charged reflect a representative share of the costs incurred to serve them, these customers could terminate their agreements early or reduce minimum capacity levels. These agreements include exit fees for early termination and fees for capacity reductions, but these fees may not fully mitigate this risk. Although assets constructed or acquired to serve these customers will also be used to serve other Ameren Missouri customers, early termination or capacity reductions could impact Ameren Missouri’s ability to fully recover its investment in, and return on, those assets. Also, the Ameren Companies may not be able to provide the necessary electric service, including both energy and capacity, within the time periods required by large load customers. The Ameren Companies may need to accelerate the addition of generation resources within current plans, obtain new generation resources, expand transmission or distribution facilities that are not currently within their plans, or purchase additional energy and capacity to meet the increase in demand. In addition, demand for construction services within the utility industry has increased significantly due to growing energy demand and energy transition, creating limited availability of suppliers, contractors, and developers, which could impact the Ameren Companies' ability to timely construct or acquire assets needed to meet forecasted demand. If the Ameren Companies are required to purchase energy and capacity to meet demand, their risk management and liquidity levels may not be effective at mitigating price impacts of such purchases, or there may not be sufficient energy and capacity available, either of which could negatively impact the Ameren Companies’ ability to realize forecasted or other potential demand. The Ameren Companies may not be able to plan, receive regulatory approvals, and execute those plans in a timely manner, which could result in the Ameren Companies not realizing forecasted or other potential demand.
Read it in 10-K 2026-02-18 at sec.gov ↗
RemovedRisk Factors
In addition, in June 2024, the MoPSC issued a financing order authorizing the issuance of securitized utility tariff bonds by a wholly owned, special purpose subsidiary of Ameren Missouri to finance approximately $476 million of costs related to the accelerated retirement of the Rush Island Energy Center, which included the remaining unrecovered net plant balance associated with the facility, among other costs. Ameren Missouri will collect the amounts necessary to repay the bonds over approximately 15 years from the date of bond issuance. The securitized tariff bonds were issued in December 2024. The financing order also included a determination that the decision to retire the Rush Island Energy Center was reasonable and prudent. The MoPSC did not make a determination regarding the prudency of Ameren Missouri's prior actions that resulted in the adverse ruling in the NSR and Clean Air Act litigation discussed in Note 14 – Commitments and Contingencies under Part II, Item 8, of this report, however, claims regarding such actions could be considered in future regulatory proceedings. If future regulatory proceedings result in revenue reductions based on Ameren Missouri’s prior actions that resulted in the adverse ruling in the NSR and Clean Air Act litigation, it could have a material adverse effect on the results of operations, financial position, and liquidity of Ameren and Ameren Missouri.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedRisk Factors
Ameren Illinois’ electric distribution service business is also subject to performance metrics. Failure to achieve the metrics would result in a reduction in the company’s allowed ROE calculated under the MYRP. In 2022, the ICC issued an order approving total ROE incentives and penalties of 24 basis points under the MYRP, allocated among seven performance metrics. These performance metrics include improvements in service reliability in both the frequency and duration of outages, a reduction in peak loads, an increased percentage of
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedRisk Factors
spend with diverse suppliers, a reduction in disconnections for certain customers, and improved timeliness in response to customer requests for interconnection of distributed energy resources. These performance metrics apply annually from 2024 through 2027 under the MYRP, and the impact of any incentives and penalties will be excluded from the reconciliation cap described above. In addition, the allowed ROE on energy-efficiency investments can be increased or decreased up to 200 basis points, depending on the achievement of annual energy savings goals. Any adjustments to the allowed ROE for energy-efficiency investments will depend on annual performance for a historical period relative to energy savings goals.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedRisk Factors
In April 2024, the EPA issued a final rule that sets CO2 emission standards for existing coal-fired and new natural gas-fired power plants based on the emissions expected from adoption of carbon capture technology and/or natural gas co-firing for coal-fired power plants and
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedRisk Factors
carbon capture technology for new natural gas-fired power plants. Affected power plants are required to comply with the rule through a phased-in approach or retire. Compliance with the new rule could be required as early as 2030 for certain existing coal-fired power plants and 2032 for certain new natural gas-fired power plants. In December 2024, the United States Court of Appeals for the District of Columbia Circuit heard arguments from various stakeholders including the EPA, environmental organizations, state attorney generals, and industry groups regarding the legal merits of the final rule. In February 2025, the EPA requested that the appellate court suspend the case for 60 days and not issue an opinion so the EPA can decide how to proceed. Ameren and Ameren Missouri estimate capital expenditures of approximately $580 million may be necessary to comply with the final rule assuming it is not revised or overturned. Ameren and Ameren Missouri are monitoring the legal challenges and assessing the impacts of the final rule and, at this time, cannot predict the final impacts on their results of operations, financial position, and liquidity.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedRisk Factors
Our aging infrastructure may pose risks to system reliability and expose us to expedited or unplanned significant capital expenditures and operating costs. Both of Ameren Missouri’s coal-fired energy centers were constructed prior to 1978, and the Callaway Energy Center began operating in 1984. The age of these energy centers increases the risks of unplanned outages, reduced generation output, and higher
Read it in 10-K 2025-02-18 at sec.gov ↗
RewordedRisk Factors
With respect to the transition of Ameren Missouri’s generation fleet that will be included in its 2025 Change to the 2023 PRP and carbon emission reduction targets, factors also include Ameren Missouri’s ability to obtain CCNs from the MoPSC, and any other required state or federal approvals for the addition of renewable resources, battery storage, or nuclear or natural gas-fired generation, retirement of energy centers, and new or continued customer energy-efficiency programs; the ability to enter into agreements for renewable, natural gas-fired, or nuclear generation or battery storage and acquire or construct that generation those resources at a reasonable cost; the ability to enter into natural gas supply agreements at reasonable prices and adequate quantities to power Ameren Missouri’s natural gas-fired energy centers; the ability to obtain NRC approval for an extension of the operating license for the Callaway Energy Center beyond its current 2044 expiration date; the continued existence and ability to qualify for, and use or transfer, federal production or investment tax credits; the cost of wind, solar, and other renewable generation and battery storage technologies; the cost of natural gas or hydrogen CT technologies; the cost of nuclear generation; the ability to maintain system reliability during and after the transition to clean energy generation; reliability; new and/or changes in environmental regulations, including those related to CO2 and other greenhouse gas emissions; energy prices; and demand.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
Based on its assumptions at December 31, 2024, 2025, its investment performance in 2024, 2025, and its pension funding policy, Ameren does not expect to make material contributions in 2025 and expects to make aggregate annual contributions of $170 approximately $45 million to $50 million in 2026 through 2029. each of the next five years, with aggregate estimated contributions of $240 million.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
Further, federal, state, and local authorities, including the United States Congress, authorities have considered initiatives to further restrict greenhouse gases to address global climate change, and the EPA previously announced plans to implement new climate change programs, including regulation of greenhouse gas emissions from the utility industry. climate-related risks.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
Regulations implementing To the extent our operations impact surface water bodies, including wetlands, the Clean Water Act govern potential impacts from our operations on water bodies including wetlands subject to the Act, requires permitting as well as evaluation of the ecological and biological impact of those operations.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
Achievement of these targets is dependent on many factors, including the pace and extent of development and deployment of low- to zero-carbon energy technologies and carbon capture technologies, the cost of those technologies, and support of such technologies by regulators; natural gas and energy prices; operational performance of low- to zero-carbon resources; new transmission infrastructure; the ability to maintain system reliability during and after the transition to clean reliability; customer demand for energy generation; including carbon-free energy; and constructive energy and economic policies, including those that address investment in energy infrastructure, global climate change, climate-related risks, incentives for clean energy technologies, and environmental regulations.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
Cyber attacks could include viruses, malicious or destructive code, phishing or quishing social engineering attacks, denial of service attacks, supply chain attacks, ransomware and other extortion-based attacks, improper access by third parties, attacks on email systems, and attacks leading to data loss, including data stored using cloud technologies, operational control, or exploitation of vulnerabilities specific to internally developed systems or to those provided and/or maintained by our suppliers, including those attacks arising from or generated by artificial intelligence, among various other security breaches. suppliers.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
The current federal administration is expected to review, EPA has revised, and has already revised, proposed revisions to, compliance requirements under a number of federal environmental regulatory programs; programs related to greenhouse gases; however, differences in energy policy priorities adopted by future federal presidential administrations could result in additional greenhouse gas reduction requirements in the United States.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
The Ameren Companies may or may not experience the energy demand growth currently being forecasted depending on the decisions of potential new customers about whether to locate their operations within our service territories. territories or whether customers that have signed electric service agreements begin operations within the expected timeframes.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
The resulting increase to the revenue requirement needed to recover such costs and earn a return on investments This could result in more frequent regulatory rate reviews and requests for cost recovery mechanisms.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
As of December 31, 2024, 2025, coal inventory was near targeted levels at the Labadie Energy Center and Sioux energy centers were at targeted levels. levels at the Sioux Energy Center.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
The payments related to the minimum tax by Ameren Missouri, Ameren Illinois, and ATXI are expected to be recovered, subject to approval by their respective regulators.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedRisk Factors
Pursuant to a Missouri law, the PPRA, Ameren Missouri’s PISA election was extended through December 2028 2035 and an additional extension through December 2033 2040 is allowed if requested by Ameren Missouri and approved by the MoPSC, among other things. MoPSC.
Read it in 10-K 2026-02-18 at sec.gov ↗
Quiet changesRisk Factors
Further reductions to emissions limits will become effective between 2030 and 2040, resulting in the possible closure of the Venice Energy Center by the end of 2029.
Read it in 10-K 2026-02-18 at sec.gov ↗
Quiet changesRisk Factors
About 97% Approximately 96% of Ameren Missouri’s coal is purchased from the Powder River Basin in Wyoming, which has a limited number of suppliers.
Read it in 10-K 2026-02-18 at sec.gov ↗
Quiet changesRisk Factors
Our ability to successfully execute our strategic plan, including the transition of Ameren Missouri’s generation fleet that will be included in its 2025 Change to the 2023 PRP, may affect customers’, investors’, legislators’, regulators’, creditors’, and rating agencies’ opinions and actions.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
The PPRA became effective in August 2025. The law includes certain provisions that affect the regulation of Ameren Missouri’s electric and natural gas businesses. These provisions create modifications to the PISA and integrated resource planning, require electric utilities to submit service tariff schedules for certain large load customers, allow the MoPSC to authorize inclusion of construction work in progress in rate base for new natural gas-fired generation facilities and new generation facilities approved through integrated resource planning, and allow natural gas utilities to file regulatory rate reviews using a future test year, among other things.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
In April 2025, the MoPSC issued an order in Ameren Missouri’s 2024 electric service regulatory rate review, approving nonunanimous stipulations and agreements. The order authorized an increase of $355 million to Ameren Missouri’s annual revenue requirement for electric retail service, effective June 1, 2025. The approved revenue requirement was based on infrastructure investments as of December 31, 2024. The order did not explicitly specify an ROE, capital structure, rate base, or any rate base disallowances. The order provides for the continued use of all existing riders and trackers. The order also changed annualized depreciation, regulatory asset and liability amortization amounts, and the base level of expenses for trackers. On an annualized basis, these changes reflect an increase in “Depreciation and amortization” of approximately $70 million, among other expense changes, on Ameren’s and Ameren Missouri’s consolidated statements of income.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
In July 2025, the MoPSC issued an order in Ameren Missouri’s 2024 natural gas delivery service regulatory rate review, approving a unanimous stipulation and agreement. The order authorized an increase of $32 million to Ameren Missouri’s annual revenue requirement for natural gas delivery service, effective September 1, 2025. The order did not explicitly specify an ROE, capital structure, rate base, or any rate base disallowances. The order provides for the continued use of all of Ameren Missouri’s existing riders and trackers.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
In November 2025, the MoPSC approved Ameren Missouri’s request to modify its existing large primary service tariff to require customers requesting 75 MWs or more of demand and who are served at transmission level voltage to comply with additional tariff terms. The additional terms include a service term of 12 years plus a ramp period of up to five years to reach peak demand, minimum demand charges of 80% of contracted capacity, customer exit terms and fees, and customer credit and collateral requirements, among other terms. In addition, new customer programs would be available under this tariff, which allow customers to support renewable generation, battery storage, and/or nuclear generation through incremental payments. The MoPSC order also includes an earnings sharing mechanism that would apply if Ameren Missouri’s earned ROE for a calendar year exceeds 9.74%, which can be adjusted by the MoPSC in future electric rate orders. If this were to occur, Ameren Missouri would defer 65% of the return in excess of the 9.74% ROE to a regulatory liability, which would be returned to retail electric customers in a future rate review. In addition, if large load customer revenues were reduced in a calendar year due to certain events, as determined by the MoPSC, Ameren Missouri may defer a portion of the reduced revenues to a regulatory asset to be included in its revenue requirement in the next electric rate review. In February 2026, Ameren Missouri executed electric service agreements with large load customers consistent with the tariff terms discussed above, representing 2.2 gigawatts of demand. Ameren and Ameren Missouri do not expect a material impact to their results of operations, financial position, or liquidity in 2026 related to these agreements.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
In August 2025, Ameren Missouri filed for a CCN to construct the Reform Solar Project (250-MW facility). Ameren Missouri expects a decision by the MoPSC in the first half of 2026. In February 2026, the MoPSC issued an order approving a nonunanimous stipulation and agreement related to a requested CCN for the Big Hollow Natural Gas (800-MW facility) and the Big Hollow Battery Energy Storage (400-MW facility) projects. Also in February 2026, Ameren Missouri acquired the Split Rail Solar Project, which includes solar panels, project design, land rights, and engineering, procurement, and construction agreements, for approximately $600 million, and took over construction management of the project, which is expected to be placed in-service in the second quarter of 2026.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
In January 2026, the CRGA was enacted and will become effective in June 2026. The law includes certain provisions that affect Ameren Illinois’ electric distribution and transmission businesses. These provisions increase the annual spending cap on energy-efficiency investments beginning in 2027 and modify the ROE component of the return on those investments.
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
Earnings per diluted share in 2025, compared with 2024, were favorably affected by:
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
•decreased income tax expense at Ameren Transmission, Ameren Illinois Electric Distribution and Ameren Illinois Natural Gas resulting from the revaluation of excess deferred income tax regulatory liabilities, resulting from TCJA for FERC-regulated and ICC-regulated jurisdictions, related to ratemaking treatment of net operating loss carryforwards by affiliates under a tax allocation agreement, see Note 12 – Income Taxes under Part II, Item 8, of this report for additional information (32 cents per share);
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
•a higher allowance for equity funds used during construction at Ameren Transmission (4 cents per share).
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
Earnings per diluted share in 2025, compared with 2024, were unfavorably affected by:
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
•increased losses related to equity method investments at Ameren Transmission and Ameren (parent) (4 cents per share).
Read it in 10-K 2026-02-18 at sec.gov ↗
AddedMD&A
Revenues; Fuel and Purchased Power Expenses; Other Operations and Maintenance Expenses; Depreciation and Amortization Expenses; Taxes Other Than Income Taxes; Other Income, Net; Interest Charges; and Income Taxes, see the major headings below.
Read it in 10-K 2026-02-18 at sec.gov ↗
RemovedMD&A
In September 2023, the United States District Court for the Eastern District of Missouri granted Ameren Missouri’s request to modify a September 2019 remedy order issued by the district court in order to allow the retirement of the Rush Island Energy Center in advance of its previously expected retirement date of 2039, in lieu of installing a flue gas desulfurization system. Ameren Missouri retired the Rush Island Energy Center on October 15, 2024. In December 2024, the United States District Court for the Eastern District of Missouri issued an order resolving all outstanding claims in this case. The order requires Ameren Missouri to fund a program to provide electric buses and charging stations to schools in the metro St. Louis area and a program to provide air purifiers to eligible Ameren Missouri electric residential customers. These programs are estimated to cost approximately $64 million. As of December 31, 2024, Ameren and Ameren Missouri recorded liabilities of $64 million and charges of $59 million in 2024 related to the cost of these programs.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
In June 2024, Ameren Missouri filed a request with the MoPSC seeking approval to increase its annual revenues for electric service. In February 2025, Ameren Missouri filed an updated electric rate increase request seeking approval to increase its annual revenues for electric service by $446 million. The electric rate increase request is based on a 10.25% ROE, a capital structure composed of 52% common equity, a rate base of $13.9 billion, and a test year ended March 31, 2024, with certain pro-forma adjustments through the true-up date of December 31, 2024. In February 2025, the MoPSC staff recommended an increase to Ameren Missouri's annual electric service revenues of $384 million based on a 9.74% ROE, a capital structure composed of 52% common equity, and a rate base of $13.9 billion. The MoPSC proceeding relating to the proposed electric service rate changes will take place over a period of up to 11 months, with a decision by the MoPSC expected by May 2025 and new rates effective by June 2025.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
In June 2024, the MoPSC issued a financing order authorizing the issuance of securitized utility tariff bonds by AMF to finance $476 million of costs related to the accelerated retirement of the Rush Island Energy Center, which included the remaining unrecovered net plant balance associated with the facility, among other costs. Ameren Missouri will collect the amounts necessary to repay the bonds over approximately 15 years from the date of bond issuance. The securitized tariff bonds were issued in December 2024. The financing order also included a determination that the decision to retire the Rush Island Energy Center was reasonable and prudent. The MoPSC did not make a determination regarding the prudency of Ameren Missouri's prior actions that resulted in the adverse ruling in the NSR and Clean Air Act litigation discussed in Note 14 – Commitments and Contingencies under Part II, Item 8, of this report, however, claims regarding such actions could be considered in future regulatory proceedings. If future regulatory proceedings result in revenue reductions based on Ameren Missouri’s prior actions that resulted in the adverse ruling in the NSR and Clean Air Act litigation, it could have a material adverse effect on the results of operations, financial position, and liquidity of Ameren and Ameren Missouri.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
In 2024, the MoPSC issued orders approving requested CCNs for the Split Rail, Vandalia, Bowling Green, and Cass County solar projects. Ameren Missouri acquired the Cass County, Boomtown, and Huck Finn solar projects in June 2024, September 2024, and October 2024, respectively, and placed the assets of the projects, totaling $1 billion, in service in December 2024. In October 2024, the MoPSC issued an order approving a nonunanimous stipulation and agreement filed by Ameren Missouri, the MoPSC staff, and other intervenors requesting a CCN for the Castle Bluff Natural Gas Project. The order also includes the use of a post-construction cost deferral related to the project, which allows Ameren Missouri to defer and recover depreciation expense, financing costs, and applicable income taxes incurred from the date the project is placed in service to the date when project costs are reflected in updated base rates as a result of a regulatory rate review. The period of deferral would be limited to the earlier of the time the project costs are reflected in base rates or six months.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
In September 2024, Ameren Missouri filed a request with the MoPSC seeking approval to increase its annual revenues for natural gas delivery service by $40 million. The natural gas rate increase request is based on a 10.25% ROE, a capital structure composed of 52% common equity, a rate base of $531 million, and a test year ended March 31, 2024, with certain pro-forma adjustments expected through the true-up date of December 31, 2024. The MoPSC proceeding relating to the proposed natural gas delivery service rate changes will take place over a period of up to 11 months, with a decision by the MoPSC expected by August 2025 and new rates effective by September 2025.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
In November 2024, the MoPSC issued an order approving a nonunanimous stipulation and agreement for Ameren Missouri’s MEEIA 2025 plan, which includes a portfolio of customer energy-efficiency and demand response programs, along with the continued use of the MEEIA rider, which allows Ameren Missouri to collect from customers its actual MEEIA program costs, related lost electric revenues, and performance incentives. Ameren Missouri intends to invest $51 million annually in 2025 and 2026 and $22 million in 2027 for customer energy-efficiency and demand response programs. In addition, the order approved performance incentives applicable to each plan year to earn revenues by achieving certain spending and demand response goals. If 100% of the goals are achieved in 2025, 2026, and 2027, Ameren Missouri would earn performance incentive revenues of $5 million, $5 million, and $2 million, respectively.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
transmission capital investments included in the order, among other things. In January 2024, the ICC denied Ameren Illinois’ rehearing request, and Ameren Illinois filed an appeal with the Illinois Appellate Court for the Fifth Judicial District. In January 2025, the appellate court ruled on the appeal filed by Ameren Illinois. In that ruling, the court reversed a reduction of planned transmission capital investments of $48 million, but affirmed the ICC-approved 9.44% ROE and the remaining reduction of planned distribution capital investments. Ameren Illinois took prudent steps to align its operations with the ICC order, while continuing to ensure safe and adequate service is maintained.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
billion. Ameren Illinois used a 2026 future test year in this proceeding. A decision by the ICC in this proceeding is required by early December 2025, with new rates expected to be effective in December 2025.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
In October 2024, the FERC issued an order, which decreased the allowed base ROE for FERC-regulated transmission rate base under the MISO tariff from 10.02% to 9.98% and required refunds, with interest, for the periods from November 2013 to February 2015 and from late September 2016 forward. In November 2024, the MISO transmission owners, including Ameren Missouri, Ameren Illinois, and ATXI, filed a request for rehearing with the FERC, arguing, among other things, the FERC should not have ordered refunds back to September 2016 or imposed interest on those refunds. Also in November 2024, another intervenor filed a request for rehearing with the FERC, requesting the FERC correct aspects of the ROE methodology used in the October 2024 order and reconsider its decision in a February 2015 complaint case to deny refunds for the period from February 2015 to May 2016. In December 2024, the FERC issued a notice indicating a future order related to the rehearing requests will be issued but did not specify a timeline. In January 2025, the MISO transmission owners, including Ameren Missouri, Ameren Illinois, and ATXI, filed an appeal of the October 2024 order to the United States Court of Appeals for the District of Columbia Circuit. As a result of the October 2024 order, Ameren and Ameren Illinois recognized reductions to electric revenues of $10 million and $7 million, respectively, and recognized interest expense of $2 million and $1 million, respectively, on their statements of income in 2024.
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
•increased base rate revenues at Ameren Illinois Natural Gas effective November 28, 2023, pursuant to the November 2023 ICC natural gas rate order, partially offset by increased depreciation and amortization expenses included in base rates (4 cents per share); and
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
•increased taxes other than income taxes at Ameren Missouri, largely resulting from the absence in 2024 of employee retention tax credits received under the Coronavirus Aid, Relief, and Economic Security Act (2 cents per share).
Read it in 10-K 2025-02-18 at sec.gov ↗
RemovedMD&A
(d)The electric deferred income tax adjustment relates to certain excess deferred income taxes that will be amortized through 2025. Offsetting expense increases or decreases are reflected within "Income Taxes" on the statement of income. This item has no overall impact on earnings.
Read it in 10-K 2025-02-18 at sec.gov ↗
RewordedMD&A
Base rates (estimate)(b) $ 62 249 $ 14 96 $ — $ 89 81 $ — $ 165 426 Effect of weather (estimate)(c) 3 66 — — — — 3 66 Retail sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA) 27 20 — — — — 27 Customer charges 2 20 RESRAM(d) (23) — — — — 2 (23) Rush Island Energy Center base rate revenue deferral (13) — — — — (13) MEEIA 2019 performance incentives 1 Securitized utility tariff bond surcharges 46 — — — — 1 46 Off-system sales, capacity, transmission, and FAC revenues, net 96 452 — — — — 96 Recovery of power restoration efforts provided to other utilities 1 3 — — — 4 452 Ameren Illinois energy-efficiency program investment revenues — 21 12 — — — 21 Electric deferred income tax adjustment(d) — (23) 12 Other 4 18 — — — (23) Other 6 4 — 15 (15) 10 (6) 16 Cost recovery mechanisms – offset in fuel and purchased power(e) (54) (193) (12) 201 — — (12) (259) (41) 148 Other cost recovery mechanisms(f) 22 45 (5) (17) — — — 67 (22) Total electric revenue change $ 153 784 $ (129) 310 $ — $ 104 81 $ (27) (47) $ 101 1,128 Natural gas revenue change:
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Ameren Missouri’s ability to obtain CCNs from the MoPSC, and any other required state or federal approvals for the addition of renewable resources, battery storage, or nuclear or natural gas-fired generation, retirement of energy centers, and new or continued customer energy-efficiency programs; the ability to enter into agreements for renewable, natural gas-fired, or nuclear generation or battery storage and acquire or construct that generation those resources at a reasonable cost; the ability of suppliers, contractors, and developers to meet contractual commitments and timely complete projects, projects timely, which is dependent upon the availability of necessary labor, materials, and equipment, geopolitical conflict, or government actions, among other things; changes in the scope and timing of projects; the ability to enter into natural gas supply agreements at reasonable prices and adequate quantities to power Ameren Missouri’s natural gas-fired energy centers; the continued existence and ability to qualify for, and use or transfer, federal production or investment tax credits; the ability to maintain system reliability; new and/or changes in environmental regulations, including those related to CO2 and other greenhouse gas emissions; energy prices; and demand;
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
DRPlus and 401(k)(b)(c) Various $ 44 $ 40 $ 47 ATM program(d) Various 530 233 299 Total Ameren common stock issuances(e) $ 574 $ 273 $ 346 Maturities of Long-term Debt Ameren: 2.50% Senior unsecured notes due 2024 September $ — $ 450 $ Ameren Missouri: 3.50% Senior secured notes due 2024 April — 350 4.85% Securitized utility tariff bonds due 2039(a) October 17 — Ameren Missouri: Illinois: 3.25% First mortgage bonds due 2025 June 300 — ATXI: 3.43% Senior unsecured notes due 2050 August — 49 Total Ameren long-term debt maturities $ 317 (f) $ 849 (f)
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Month Issued, Redeemed, Repurchased, or Matured 2025 2024 2023 Issuances of Long-term Debt Ameren: 5.70% 5.375% Senior unsecured notes due 2026 November 2035 March $ 749 $ — $ 599 5.00% Senior unsecured notes due 2029 December — 699 Ameren Missouri: 5.25% First mortgage bonds due 2054 January — 347 — 5.45% 5.25% First mortgage bonds due 2053 March 2035 April 500 — 499 5.20% First mortgage bonds due 2034 April — 499 — 5.125% First mortgage bonds due 2055 October — 449 — 4.85% Securitized utility tariff bonds due 2039(a) December — 476 — Ameren Illinois: 4.95% 5.625% First mortgage bonds due 2033 May 2055 March 350 — 498 5.55% First mortgage bonds due 2054 June — 624 5.625% First mortgage bonds due 2055 September 361 — ATXI: 5.17% Senior unsecured notes due 2039 August — 70 — 5.42% Senior unsecured notes due 2053 August — 70 — Total Ameren long-term debt issuances $ 1,960 $ 2,535 $ 2,295 Issuances of Common Stock Ameren:
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Energy costs (excluding the estimated effect of weather) $ 95 459 $ — $ $ $ — $ 95 459 Effect of higher net energy costs included in base rates 22 weather (estimate)(a) 11 — — — — 22 Retail sales volumes 6 11 Transmission service charges 10 — — — — 6 Transmission service charges 8 10 Other (1) — — — — 8 Other (3) — — — — (2) (3) Cost recovery mechanisms – offset in electric revenue(a) (54) (193) revenue(b) (12) 201 — — (12) (259) (41) 148 Total fuel and purchased power change $ 74 467 $ (193) 201 $ $ $ (12) (43) $ (131) 625
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Base rates (estimate) $ 9 $ — $ 4 $ — $ — $ 47 $ — $ — $ 47 Sales volume (excluding the estimated effects 13 Effect of weather) 2 weather (estimate)(c) 12 — — — — 2 Effect of weather (estimate)(c) 12 Other 1 — — — — 1 Other — — 3 — — 3 Cost recovery mechanisms – offset in natural gas purchased for resale(e) (20) (4) — (16) 23 — — (36) 19 Other cost recovery mechanisms(f) (2) — 7 — — 5 3 — — 3 Total natural gas revenue change $ (19) 18 $ — $ 41 30 $ — $ — $ 22 48
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
In addition to changes by segment as segments discussed below, other operations and maintenance expenses decreased $34 $18 million in 2024 for activity not reported as part of a segment, as reflected in “Other/Intersegment Eliminations” above, primarily because of a $14 million increase in the elimination of intercompany rent related to ATXI’s operations control center discussed below; a $10 million increase in the elimination of the non-service cost component of net periodic benefit income at Ameren Services; and a $8 million gain on the sale of land. above.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Other income, net, decreased $2 $16 million in 2024, 2025, compared with 2023 2024, primarily due to a decrease of $5 million in lower allowance for equity funds used during construction, primarily related to lower average construction work in progress balances and a decrease of $2 $13 million in the reduction in non-service cost component of net periodic benefit income. income and an increase of $5 million in charitable donations.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Ameren Illinois’ cash used in investing activities decreased $267 increased $18 million during 2024, 2025, compared with 2023, 2024, due to a decrease an increase in capital expenditures, largely resulting from increased expenditures for natural gas and electric distribution infrastructure upgrades as well as increased expenditures related to major storms, partially offset by decreased expenditures for electric transmission infrastructure upgrades. infrastructure.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Depreciation and amortization expenses increased $203 million, $134 million, decreased $22 million and $63 $57 million at Ameren, Ameren and Ameren Missouri, respectively, and increased $33 million at Ameren Illinois, respectively, primarily because of additional property, plant, and equipment investments across their respective segments. Illinois.
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Base rate Additionally, revenues were unfavorably favorably affected by a decrease in the allowed base ROE under the MISO tariff resulting from absence of the October 2024 FERC order, which included customer refunds order that decreased base ROE for certain historical periods (-$7 (+$10 million).
Read it in 10-K 2026-02-18 at sec.gov ↗
RewordedMD&A
Base rate Additionally, revenues were unfavorably favorably affected by a decrease in the allowed base ROE under the MISO tariff resulting from absence of the October 2024 FERC order, which included customer refunds order that decreased base ROE for certain historical periods (-$7 (+$7 million).
Read it in 10-K 2026-02-18 at sec.gov ↗
Quiet changesMD&A
Related to these projects, Ameren began substation upgrades in May 2024 in advance of transmission line construction, which is expected to begin in spring 2026, with forecasted completion dates near the end of this decade.
Read it in 10-K 2026-02-18 at sec.gov ↗
Quiet changesMD&A
Related to these projects, Ameren began substation upgrades in May 2024 in advance of transmission line construction, which is expected to begin in spring 2026, with forecasted completion dates near the end of this decade.
Read it in 10-K 2026-02-18 at sec.gov ↗
Quiet changesMD&A
Ameren Illinois will reconcile reconciles its actual revenue requirement, as adjusted for certain cost variations, to ICC-approved electric distribution service rates on an annual basis, subject to a reconciliation cap.
Read it in 10-K 2026-02-18 at sec.gov ↗
