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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 10-Q
 
Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended March 31, 2023

OR
Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
for the transition period from             to
Ameren Missouri Logo.jpg
Ameren Logo.jpg
Ameren Illinois Logo.jpg
Commission
File Number
Exact name of registrant as specified in its charter;
State of Incorporation;
Address and Telephone Number
IRS Employer
Identification No.
1-14756Ameren Corporation43-1723446
(Missouri Corporation)
1901 Chouteau Avenue
St. Louis, Missouri 63103
(314) 621-3222
1-2967Union Electric Company43-0559760
(Missouri Corporation)
1901 Chouteau Avenue
St. Louis, Missouri 63103
(314) 621-3222
1-3672Ameren Illinois Company37-0211380
(Illinois Corporation)
10 Richard Mark Way
Collinsville, Illinois 62234
(618) 343-8150
Securities Registered Pursuant to Section 12(b) of the Act:
Title of each classTrading Symbol(s)Name of each exchange on which registered
Common Stock, $0.01 par value per shareAEENew York Stock Exchange


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Indicate by check mark whether the registrants: (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) have been subject to such filing requirements for the past 90 days.
Ameren CorporationYesNo
Union Electric CompanyYesNo
Ameren Illinois CompanyYesNo
Indicate by check mark whether each registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).
Ameren CorporationYesNo
Union Electric CompanyYesNo
Ameren Illinois CompanyYesNo
Indicate by check mark whether each registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Ameren CorporationLarge accelerated filerAccelerated filerNon-accelerated filer
Smaller reporting companyEmerging growth company
Union Electric CompanyLarge accelerated filerAccelerated filerNon-accelerated filer
Smaller reporting companyEmerging growth company
Ameren Illinois CompanyLarge accelerated filerAccelerated filerNon-accelerated filer
Smaller reporting companyEmerging growth company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
Ameren Corporation
Union Electric Company
Ameren Illinois Company
Indicate by check mark whether each registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).
Ameren CorporationYesNo
Union Electric CompanyYesNo
Ameren Illinois CompanyYesNo
The number of shares outstanding of each registrant’s classes of common stock as of April 28, 2023, was as follows:
RegistrantTitle of each class of common stockShares outstanding
Ameren CorporationCommon stock, $0.01 par value per share262,609,472 
Union Electric CompanyCommon stock, $5 par value per share, held by Ameren Corporation102,123,834 
Ameren Illinois CompanyCommon stock, no par value, held by Ameren Corporation25,452,373 

This combined Form 10-Q is separately filed by Ameren Corporation, Union Electric Company, and Ameren Illinois Company. Each registrant hereto is filing on its own behalf all of the information contained in this quarterly report that relates to such registrant. Each registrant hereto is not filing any information that does not relate to such registrant, and therefore makes no representation as to any such information.


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TABLE OF CONTENTS
  Page
Item 1.
Union Electric Company (d/b/a Ameren Missouri)
Consolidated Statement of Income
Consolidated Balance Sheet
Ameren Illinois Company (d/b/a Ameren Illinois)
Item 2.
Item 3.
Item 4.
Item 1.
Item 1A.
Item 2.
Item 6.


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GLOSSARY OF TERMS AND ABBREVIATIONS
We use the words “our,” “we” or “us” with respect to certain information that relates to Ameren, Ameren Missouri, and Ameren Illinois, collectively. When appropriate, subsidiaries of Ameren Corporation are named specifically as their various business activities are discussed. Refer to the Form 10-K for a complete listing of glossary terms and abbreviations. Only new or significantly changed terms and abbreviations are included below.
CCN – Certificate of convenience and necessity.
Form 10-K – The combined Annual Report on Form 10-K for the year ended December 31, 2022, filed by the Ameren Companies with the SEC.

FORWARD-LOOKING STATEMENTS
Statements in this report not based on historical facts are considered “forward-looking” and, accordingly, involve risks and uncertainties that could cause actual results to differ materially from those discussed. Although such forward-looking statements have been made in good faith and are based on reasonable assumptions, there is no assurance that the expected results will be achieved. These statements include (without limitation) statements as to future expectations, beliefs, plans, projections, strategies, targets, estimates, objectives, events, conditions, and financial performance. In connection with the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, we are providing this cautionary statement to identify important factors that could cause actual results to differ materially from those anticipated. The following factors, in addition to those discussed within Risk Factors in the Form 10-K, and elsewhere in this report and in our other filings with the SEC, could cause actual results to differ materially from management expectations suggested in such forward-looking statements:
regulatory, judicial, or legislative actions, and any changes in regulatory policies and ratemaking determinations, that may change regulatory recovery mechanisms, such as those that may result from the impact of a final ruling to be issued by the United States District Court for the Eastern District of Missouri regarding its September 2019 remedy order for the Rush Island Energy Center, the MoPSC staff review of the planned Rush Island Energy Center retirement, Ameren Missouri’s electric regulatory rate review filed in August 2022 with the MoPSC, Ameren Missouri’s proposed customer energy-efficiency plan under the MEEIA filed with the MoPSC in March 2023, Ameren Illinois’ MYRP electric distribution service regulatory rate review filed in January 2023 with the ICC, Ameren Illinois’ natural gas regulatory rate review filed in January 2023 with the ICC, Ameren Illinois’ electric distribution service revenue requirement reconciliation adjustment request filed with the ICC in April 2023, and the August 2022 United States Court of Appeals for the District of Columbia Circuit ruling that vacated FERC’s MISO ROE-determining orders and remanded the proceedings to the FERC;
our ability to control costs and make substantial investments in our businesses, including our ability to recover costs and investments, and to earn our allowed ROEs, within frameworks established by our regulators, while maintaining affordability of our services for our customers;
the effect of Ameren Illinois’ use of the performance-based formula ratemaking framework for its electric distribution service under the IEIMA, which established and allows for a reconciliation of electric distribution service rates through 2023, its participation in electric energy-efficiency programs, and the related impact of the direct relationship between Ameren Illinois’ ROE and the 30-year United States Treasury bond yields;
the effect and duration of Ameren Illinois’ election to utilize MYRPs for electric distribution service ratemaking effective for rates beginning in 2024, including the effect of the reconciliation cap on the electric distribution revenue requirement;
the effect on Ameren Missouri of any customer rate caps or limitations on increasing the electric service revenue requirement pursuant to Ameren Missouri’s election to use the PISA;
Ameren Missouri’s ability to construct and/or acquire wind, solar, and other renewable energy generation facilities and battery storage, as well as natural gas-fired combined cycle energy centers, retire fossil fuel-fired energy centers, and implement new or existing customer energy-efficiency programs, including any such construction, acquisition, retirement, or implementation in connection with its Smart Energy Plan, integrated resource plan, or emissions reduction goals, and to recover its cost of investment, a related return, and, in the case of customer energy-efficiency programs, any lost margins in a timely manner, each of which is affected by the ability to obtain all necessary regulatory and project approvals, including CCNs from the MoPSC or any other required approvals for the addition of renewable resources;
Ameren Missouri’s ability to use or transfer federal production and investment tax credits related to renewable energy projects; the cost of wind, solar, and other renewable generation and storage technologies; and our ability to obtain timely interconnection agreements with the MISO or other RTOs at an acceptable cost for each facility;
the success of competitive bids related to requests for proposals associated with the MISO’s long-range transmission planning;
the inability of our counterparties to meet their obligations with respect to contracts, credit agreements, and financial instruments, including as they relate to the construction and acquisition of electric and natural gas utility infrastructure and the ability of counterparties
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to complete projects, which is dependent upon the availability of necessary materials and equipment, including those obligations that are affected by supply chain disruptions;
advancements in energy technologies, including carbon capture, utilization, and sequestration, hydrogen fuel for electric production and energy storage, next generation nuclear, and large-scale long-cycle battery energy storage, and the impact of federal and state energy and economic policies with respect to those technologies;
the effects of changes in federal, state, or local laws and other governmental actions, including monetary, fiscal, foreign trade, and energy policies;
the effects of changes in federal, state, or local tax laws or rates, including the effects of the IRA and the 15% minimum tax on adjusted financial statement income, as well as additional regulations, interpretations, amendments, or technical corrections to or in connection with the IRA, and challenges, if any, to the tax positions taken by the Ameren Companies, as well as resulting effects on customer rates and the recoverability of the minimum tax imposed under the IRA;
the effects on energy prices and demand for our services resulting from technological advances, including advances in customer energy efficiency, electric vehicles, electrification of various industries, energy storage, and private generation sources, which generate electricity at the site of consumption and are becoming more cost-competitive;
the cost and availability of fuel, such as low-sulfur coal, natural gas, and enriched uranium used to produce electricity; the cost and availability of natural gas for distribution and purchased power, including capacity, zero emission credits, renewable energy credits, and emission allowances; and the level and volatility of future market prices for such commodities and credits;
disruptions in the delivery of fuel, failure of our fuel suppliers to provide adequate quantities or quality of fuel, or lack of adequate inventories of fuel, including nuclear fuel assemblies from the one NRC-licensed supplier of Ameren Missouri’s Callaway Energy Center assemblies;
the cost and availability of transmission capacity for the energy generated by Ameren Missouri’s energy centers or required to satisfy our energy sales;
the effectiveness of our risk management strategies and our use of financial and derivative instruments;
the ability to obtain sufficient insurance, or, in the absence of insurance, the ability to timely recover uninsured losses from our customers;
the impact of cyberattacks and data security risks on us or our suppliers, which could, among other things, result in the loss of operational control of energy centers and electric and natural gas transmission and distribution systems and/or the loss of data, such as customer, employee, financial, and operating system information;
acts of sabotage, which have increased in frequency and severity within the utility industry, war, terrorism, or other intentionally disruptive acts;
business, economic, and capital market conditions, including the impact of such conditions on interest rates, inflation, and investments;
the impact of inflation or a recession on our customers and the related impact on our results of operations, financial position, and liquidity;
disruptions of the capital and credit markets, deterioration in credit metrics of the Ameren Companies, or other events that may have an adverse effect on the cost or availability of capital, including short-term credit and liquidity, and our ability to access the capital and credit markets on reasonable terms when needed;
the actions of credit rating agencies and the effects of such actions;
the impact of weather conditions and other natural phenomena on us and our customers, including the impact of system outages and the level of wind and solar resources;
the construction, installation, performance, and cost recovery of generation, transmission, and distribution assets;
the ability to maintain system reliability during the transition to clean energy generation by Ameren Missouri and the electric utility industry, including within the MISO, as well as Ameren Missouri’s ability to meet generation capacity obligations;
the effects of failures of electric generation, electric and natural gas transmission or distribution, or natural gas storage facilities systems and equipment, which could result in unanticipated liabilities or unplanned outages;
the operation of Ameren Missouri’s Callaway Energy Center, including planned and unplanned outages, as well as the ability to recover costs associated with such outages and the impact of such outages on off-system sales and purchased power, among other things;
Ameren Missouri’s ability to recover the remaining investment and decommissioning costs associated with the retirement of an energy center, as well as the ability to earn a return on that remaining investment and those decommissioning costs;
the impact of current environmental laws and new, more stringent, or changing requirements, including those related to NSR, CO2, NOx, and other emissions and discharges, Illinois emission standards, cooling water intake structures, CCR, energy efficiency, and wildlife protection, that could limit or terminate the operation of certain of Ameren Missouri’s energy centers, increase our operating costs or investment requirements, result in an impairment of our assets, cause us to sell our assets, reduce our customers’ demand for electricity or natural gas, or otherwise have a negative financial effect;
the impact of complying with renewable energy standards in Missouri and Illinois and with the zero emission standard in Illinois;
the effectiveness of Ameren Missouri’s customer energy-efficiency programs and the related revenues and performance incentives earned under its MEEIA programs;
Ameren Illinois’ ability to achieve the performance standards applicable to its electric distribution business and electric customer energy-efficiency goals and the resulting impact on its allowed ROE;
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labor disputes, work force reductions, changes in future wage and employee benefits costs, including those resulting from changes in discount rates, mortality tables, returns on benefit plan assets, and other assumptions;
the impact of negative opinions of us or our utility services that our customers, investors, legislators, regulators, creditors, or other stakeholders may have or develop, which could result from a variety of factors, including failures in system reliability, failure to implement our investment plans or to protect sensitive customer information, increases in rates, negative media coverage, or concerns about ESG practices;
the impact of adopting new accounting guidance;
the effects of strategic initiatives, including mergers, acquisitions, and divestitures;
legal and administrative proceedings;
pandemics or other health events, including the COVID-19 pandemic, and their impacts on our results of operations, financial position, and liquidity; and
the impacts of the Russian invasion of Ukraine, related sanctions imposed by the U.S. and other governments, and any broadening of the conflict, including potential impacts on the cost and availability of fuel, natural gas, enriched uranium, and other commodities, materials, and services, the inability of our counterparties to perform their obligations, disruptions in the capital and credit markets, and other impacts on business, economic, and geopolitical conditions, including inflation.
New factors emerge from time to time, and it is not possible for us to predict all of such factors, nor can we assess the impact of each such factor on the business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained or implied in any forward-looking statement. Given these uncertainties, undue reliance should not be placed on these forward-looking statements. Except to the extent required by the federal securities laws, we undertake no obligation to update or revise publicly any forward-looking statements to reflect new information or future events.
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PART I. FINANCIAL INFORMATION
ITEM 1. FINANCIAL STATEMENTS.

AMEREN CORPORATION
CONSOLIDATED STATEMENT OF INCOME AND COMPREHENSIVE INCOME
(Unaudited) (In millions, except per share amounts)
 Three Months Ended March 31,
 20232022
Operating Revenues:
Electric$1,590 $1,318 
Natural gas472 561 
Total operating revenues2,062 1,879 
Operating Expenses:
Fuel113 176 
Purchased power495 177 
Natural gas purchased for resale208 293 
Other operations and maintenance448 461 
Depreciation and amortization320 299 
Taxes other than income taxes127 142 
Total operating expenses1,711 1,548 
Operating Income351 331 
Other Income, Net78 60 
Interest Charges127 104 
Income Before Income Taxes302 287 
Income Taxes37 34 
Net Income265 253 
Less: Net Income Attributable to Noncontrolling Interests 1 1 
Net Income Attributable to Ameren Common Shareholders$264 $252 
Net Income$265 $253 
Other Comprehensive Income (Loss), Net of Taxes
Pension and other postretirement benefit plan activity, net of income taxes of $ and $, respectively
(1)1 
Comprehensive Income264 254 
Less: Comprehensive Income Attributable to Noncontrolling Interests
1 1 
Comprehensive Income Attributable to Ameren Common Shareholders$263 $253 
Earnings per Common Share – Basic$1.01 $0.98 
Earnings per Common Share – Diluted$1.00 $0.97 
Weighted-average Common Shares Outstanding – Basic262.2 257.9 
Weighted-average Common Shares Outstanding – Diluted263.1 259.0 
The accompanying notes are an integral part of these consolidated financial statements.
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AMEREN CORPORATION
CONSOLIDATED BALANCE SHEET
(Unaudited) (In millions, except per share amounts)
March 31,
2023
December 31, 2022
ASSETS
Current Assets:
Cash and cash equivalents$10 $10 
Accounts receivable – trade (less allowance for doubtful accounts of $34 and $31, respectively)
625 600 
Unbilled revenue299 446 
Miscellaneous accounts receivable62 54 
Inventories630 667 
Current regulatory assets292 354 
Investment in industrial development revenue bonds 240 
Current collateral assets29 142 
Other current assets115 155 
Total current assets2,062 2,668 
Property, Plant, and Equipment, Net31,735 31,262 
Investments and Other Assets:
Nuclear decommissioning trust fund1,019 958 
Goodwill411 411 
Regulatory assets1,599 1,426 
Pension and other postretirement benefits423 411 
Other assets815 768 
Total investments and other assets4,267 3,974 
TOTAL ASSETS$38,064 $37,904 
LIABILITIES AND EQUITY
Current Liabilities:
Current maturities of long-term debt$100 $340 
Short-term debt1,248 1,070 
Accounts and wages payable664 1,159 
Other current liabilities745 797 
Total current liabilities2,757 3,366 
Long-term Debt, Net14,181 13,685 
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes and tax credits, net3,856 3,804 
Regulatory liabilities5,395 5,309 
Asset retirement obligations769 763 
Other deferred credits and liabilities370 340 
Total deferred credits and other liabilities10,390 10,216 
Commitments and Contingencies (Notes 2, 9, and 10)
Shareholders’ Equity:
Common stock, $.01 par value, 400.0 shares authorized – shares outstanding of 262.6 and 262.0, respectively
3 3 
Other paid-in capital, principally premium on common stock6,861 6,860 
Retained earnings3,745 3,646 
Accumulated other comprehensive loss(2)(1)
Total shareholders’ equity10,607 10,508 
Noncontrolling Interests129 129 
Total equity10,736 10,637 
TOTAL LIABILITIES AND EQUITY$38,064 $37,904 
The accompanying notes are an integral part of these consolidated financial statements.
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AMEREN CORPORATION
CONSOLIDATED STATEMENT OF CASH FLOWS
(Unaudited) (In millions)
 Three Months Ended March 31,
 20232022
Cash Flows From Operating Activities:
Net income $265 $253 
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization350 324 
Amortization of nuclear fuel19 22 
Amortization of debt issuance costs and premium/discounts3 4 
Deferred income taxes and investment tax credits, net35 31 
Allowance for equity funds used during construction(9)(8)
Stock-based compensation costs8 4 
Other(6)11 
Changes in assets and liabilities:
Receivables112 (117)
Inventories37 72 
Accounts and wages payable(362)(235)
Taxes accrued50 47 
Regulatory assets and liabilities(40)75 
Assets, other(14)(10)
Liabilities, other(6)(39)
Pension and other postretirement benefits(58)(15)
Counterparty collateral, net112 (31)
Net cash provided by operating activities496 388 
Cash Flows From Investing Activities:
Capital expenditures(931)(774)
Nuclear fuel expenditures(20)(16)
Purchases of securities – nuclear decommissioning trust fund(29)(97)
Sales and maturities of securities – nuclear decommissioning trust fund17 92 
Other(1)15 
Net cash used in investing activities(964)(780)
Cash Flows From Financing Activities:
Dividends on common stock(165)(152)
Dividends paid to noncontrolling interest holders(1)(1)
Short-term debt, net179 555 
Issuances of long-term debt499  
Issuances of common stock5 5 
Employee payroll taxes related to stock-based compensation(20)(16)
Debt issuance costs(5) 
Other(3) 
Net cash provided by financing activities489 391 
Net change in cash, cash equivalents, and restricted cash21 (1)
Cash, cash equivalents, and restricted cash at beginning of year216 155 
Cash, cash equivalents, and restricted cash at end of period$237 $154 
The accompanying notes are an integral part of these consolidated financial statements.
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AMEREN CORPORATION
CONSOLIDATED STATEMENT OF SHAREHOLDERS’ EQUITY
(Unaudited) (In millions, except per share amounts)
 Three Months Ended March 31,
 20232022
Common Stock$3 $3 
Other Paid-in Capital:
Beginning of year6,860 6,502 
Shares issued under the DRPlus and 401(k) plan12 13 
Stock-based compensation activity(11)(8)
Other paid-in capital, end of period6,861 6,507 
Retained Earnings:
Beginning of year3,646 3,182 
Net income attributable to Ameren common shareholders264 252 
Dividends on common stock(165)(152)
Retained earnings, end of period3,745 3,282 
Accumulated Other Comprehensive Income (Loss):
Deferred retirement benefit costs, beginning of year(1)13 
Change in deferred retirement benefit costs(1)1 
Deferred retirement benefit costs, end of period(2)14 
Total accumulated other comprehensive income (loss), end of period(2)14 
Total Shareholders’ Equity$10,607 $9,806 
Noncontrolling Interests:
Beginning of year129 129 
Net income attributable to noncontrolling interest holders1 1 
Dividends paid to noncontrolling interest holders(1)(1)
Noncontrolling interests, end of period129 129 
Total Equity$10,736 $9,935 
Common stock shares outstanding at beginning of year262.0 257.7 
Shares issued under the DRPlus and 401(k) plan0.1 0.1 
Shares issued for stock-based compensation0.5 0.4 
Common stock shares outstanding at end of period262.6 258.2 
Dividends per common share$0.63 $0.59 
The accompanying notes are an integral part of these consolidated financial statements.
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UNION ELECTRIC COMPANY (d/b/a AMEREN MISSOURI)
CONSOLIDATED STATEMENT OF INCOME
(Unaudited) (In millions)
 Three Months Ended March 31,
 20232022
Operating Revenues:
Electric$841 $738 
Natural gas82 80 
Total operating revenues923 818 
Operating Expenses:
Fuel113 176 
Purchased power208 50 
Natural gas purchased for resale47 46 
Other operations and maintenance239 232 
Depreciation and amortization176 164 
Taxes other than income taxes80 85 
Total operating expenses863 753 
Operating Income60 65 
Other Income, Net19 23 
Interest Charges51 39 
Income Before Income Taxes28 49 
Income Taxes Benefit(1)(2)
Net Income29 51 
Preferred Stock Dividends1 1 
Net Income Available to Common Shareholder$28 $50 
The accompanying notes as they relate to Ameren Missouri are an integral part of these consolidated financial statements.
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UNION ELECTRIC COMPANY (d/b/a AMEREN MISSOURI)
CONSOLIDATED BALANCE SHEET
(Unaudited) (In millions, except per share amounts)
March 31,
2023
December 31, 2022
ASSETS
Current Assets:
Cash and cash equivalents$3 $