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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, 2022

OR
Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from             to
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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 Executive Drive
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


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 29, 2022, was as follows:
RegistrantTitle of each class of common stockShares outstanding
Ameren CorporationCommon stock, $0.01 par value per share258,226,506 
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.


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.


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.
Form 10-K – The combined Annual Report on Form 10-K for the year ended December 31, 2021, 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 in this report, 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 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, the July 2020 appeal filed by Ameren Missouri, Ameren Illinois, and ATXI challenging the refund period related to the FERC’s May 2020 order determining the allowed base ROE under the MISO tariff, the July 2020 appeal filed by Ameren Missouri, Ameren Illinois, and ATXI challenging the FERC’s rehearing denials in the transmission formula rate revision cases, and Ameren Illinois’ electric distribution service rate reconciliation request filed with the ICC in April 2022;
the length and severity of the COVID-19 pandemic, and its impacts on our business continuity plans and our results of operations, financial position, and liquidity, including but not limited to changes in customer demand resulting in changes to sales volumes; customers’ payment for our services; the health, welfare, and availability of our workforce and contractors; supplier disruptions; delays in the completion of construction projects, which could impact our expected capital expenditures and rate base growth; changes in how we operate our business and increased data security risks as a result of remote working arrangements for a significant portion of our workforce; and our ability to access the capital markets on reasonable terms and when needed;
the effect of Ameren Illinois’ use of the performance-based formula ratemaking framework for its electric distribution service under the IEIMA, which will establish and allow 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 either utilize traditional regulatory rate reviews or MYRPs for electric distribution service ratemaking effective for rates beginning in 2024;
the effect on Ameren Missouri’s investment plan and earnings if an extension to use PISA is not sought by Ameren Missouri or approved by the MoPSC;
the effect on Ameren Missouri of any customer rate caps pursuant to Ameren Missouri’s election to use the PISA, including an extension of use beyond 2023 if requested by Ameren Missouri and approved by the MoPSC under current Missouri law, or beyond 2028 if requested and approved by the MoPSC if Missouri Senate Bill 745 is enacted;
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, regulations, interpretations, or rates, and challenges to the tax positions taken by the Ameren Companies, if any, as well as resulting effects on customer rates;
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 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;
1

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 cost and availability of fuel, such as low-sulfur coal, natural gas, and enriched uranium used to produce electricity; the cost and availability of purchased power, zero emission credits, renewable energy credits, emission allowances, and natural gas for distribution; 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 Ameren Missouri’s 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 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;
business and economic conditions, which have been affected by, and will be affected by the length and severity of, the COVID-19 pandemic, including the impact of such conditions on interest rates and inflation;
disruptions of the capital 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;
the actions of credit rating agencies and the effects of such actions, including any impacts on our credit ratings that may result from the economic conditions of the COVID-19 pandemic;
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 to complete projects, which is dependent upon the availability of necessary materials and equipment, including those obligations that are affected by disruptions in the global supply chain caused by the COVID-19 pandemic;
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 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 and CO2, 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;
Ameren Missouri’s ability to construct and/or acquire wind, solar, and other renewable energy generation facilities, retire 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, related return, and, in the case of customer energy-efficiency programs, any lost margins in a timely manner, which is affected by the ability to obtain all necessary regulatory and project approvals, including certificates of convenience and necessity from the MoPSC or any other required approvals for the addition of renewable resources;
the availability of federal production and investment tax credits related to renewable energy and Ameren Missouri’s ability to use such credits; 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;
advancements in carbon-free generation and storage technologies, and the impact of constructive federal and state energy and economic policies with respect to those technologies;
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, or other stakeholders may have or develop, which could result from a variety of factors, including failures in system reliability, failure to implement our
2

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;
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, or other commodities, materials, or 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; and
acts of sabotage, war, terrorism, or other intentionally disruptive acts.
New factors emerge from time to time, and it is not possible for management to predict all of such factors, nor can it 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.
3

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,
 20222021
Operating Revenues:
Electric$1,318 $1,156 
Natural gas561 410 
Total operating revenues1,879 1,566 
Operating Expenses:
Fuel176 65 
Purchased power177 191 
Natural gas purchased for resale293 165 
Other operations and maintenance461 420 
Depreciation and amortization299 281 
Taxes other than income taxes142 128 
Total operating expenses1,548 1,250 
Operating Income331 316 
Other Income, Net60 46 
Interest Charges104 100 
Income Before Income Taxes287 262 
Income Taxes34 27 
Net Income253 235 
Less: Net Income Attributable to Noncontrolling Interests 1 2 
Net Income Attributable to Ameren Common Shareholders$252 $233 
Net Income$253 $235 
Other Comprehensive Income, Net of Taxes
Pension and other postretirement benefit plan activity, net of income taxes of $ and $, respectively
1 1 
Comprehensive Income254 236 
Less: Comprehensive Income Attributable to Noncontrolling Interests
1 2 
Comprehensive Income Attributable to Ameren Common Shareholders$253 $234 
Earnings per Common Share – Basic$0.98 $0.92 
Earnings per Common Share – Diluted$0.97 $0.91 
Weighted-average Common Shares Outstanding – Basic257.9 254.4 
Weighted-average Common Shares Outstanding – Diluted259.0 255.9 
The accompanying notes are an integral part of these consolidated financial statements.
4

AMEREN CORPORATION
CONSOLIDATED BALANCE SHEET
(Unaudited) (In millions, except per share amounts)
March 31, 2022December 31, 2021
ASSETS
Current Assets:
Cash and cash equivalents$7 $8 
Accounts receivable – trade (less allowance for doubtful accounts of $28 and $29, respectively)
560 434 
Unbilled revenue283 301 
Miscellaneous accounts receivable87 85 
Inventories520 592 
Mark-to-market derivative assets137 66 
Current regulatory assets244 319 
Current collateral assets110 66 
Other current assets83 97 
Total current assets2,031 1,968 
Property, Plant, and Equipment, Net29,578 29,261 
Investments and Other Assets:
Nuclear decommissioning trust fund1,094 1,159 
Goodwill411 411 
Regulatory assets1,377 1,289 
Pension and other postretirement benefits772 756 
Other assets934 891 
Total investments and other assets4,588 4,506 
TOTAL ASSETS$36,197 $35,735 
LIABILITIES AND EQUITY
Current Liabilities:
Current maturities of long-term debt$505 $505 
Short-term debt1,101 545 
Accounts and wages payable690 1,095 
Current regulatory liabilities219 113 
Other current liabilities630 568 
Total current liabilities3,145 2,826 
Long-term Debt, Net12,563 12,562 
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes and tax credits, net3,550 3,499 
Regulatory liabilities5,841 5,848 
Asset retirement obligations769 757 
Other deferred credits and liabilities394 414 
Total deferred credits and other liabilities10,554 10,518 
Commitments and Contingencies (Notes 2, 9, and 10)
Shareholders’ Equity:
Common stock, $.01 par value, 400.0 shares authorized – shares outstanding of 258.2 and 257.7, respectively
3 3 
Other paid-in capital, principally premium on common stock6,507 6,502 
Retained earnings3,282 3,182 
Accumulated other comprehensive income14 13 
Total shareholders’ equity9,806 9,700 
Noncontrolling Interests129 129 
Total equity9,935 9,829 
TOTAL LIABILITIES AND EQUITY$36,197 $35,735 
The accompanying notes are an integral part of these consolidated financial statements.
5

AMEREN CORPORATION
CONSOLIDATED STATEMENT OF CASH FLOWS
(Unaudited) (In millions)
 Three Months Ended March 31,
 20222021
Cash Flows From Operating Activities:
Net income $253 $235 
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization324 295 
Amortization of nuclear fuel22  
Amortization of debt issuance costs and premium/discounts4 5 
Deferred income taxes and investment tax credits, net31 26 
Allowance for equity funds used during construction(8)(7)
Stock-based compensation costs4 6 
Other11 8 
Changes in assets and liabilities:
Receivables(117)(5)
Inventories72 54 
Accounts and wages payable(235)(252)
Taxes accrued47 60 
Regulatory assets and liabilities75 (421)
Assets, other(54)(9)
Liabilities, other(26)(34)
Pension and other postretirement benefits(15)4 
Net cash provided by (used in) operating activities388 (35)
Cash Flows From Investing Activities:
Capital expenditures(774)(887)
Nuclear fuel expenditures(16)(1)
Purchases of securities – nuclear decommissioning trust fund(97)(152)
Sales and maturities of securities – nuclear decommissioning trust fund92 150 
Other15 1 
Net cash used in investing activities(780)(889)
Cash Flows From Financing Activities:
Dividends on common stock(152)(140)
Dividends paid to noncontrolling interest holders(1)(2)
Short-term debt, net555 399 
Issuances of long-term debt 450 
Issuances of common stock5 125 
Redemptions of Ameren Illinois preferred stock (13)
Employee payroll taxes related to stock-based compensation(16)(17)
Debt issuance costs (3)
Other (4)
Net cash provided by financing activities391 795 
Net change in cash, cash equivalents, and restricted cash(1)(129)
Cash, cash equivalents, and restricted cash at beginning of year155 301 
Cash, cash equivalents, and restricted cash at end of period$154 $172 
The accompanying notes are an integral part of these consolidated financial statements.
6

AMEREN CORPORATION
CONSOLIDATED STATEMENT OF SHAREHOLDERS’ EQUITY
(Unaudited) (In millions, except per share amounts)
 Three Months Ended March 31,
 20222021
Common Stock$3 $3 
Other Paid-in Capital:
Beginning of year6,502 6,179 
Settlement of forward sale agreement through common shares issuance 113 
Shares issued under the DRPlus and 401(k) plan13 12 
Stock-based compensation activity(8)(9)
Other paid-in capital, end of period6,507 6,295 
Retained Earnings:
Beginning of year3,182 2,757 
Net income attributable to Ameren common shareholders252 233 
Dividends on common stock(152)(140)
Retained earnings, end of period3,282 2,850 
Accumulated Other Comprehensive Income:
Deferred retirement benefit costs, beginning of year13 (1)
Change in deferred retirement benefit costs1 1 
Deferred retirement benefit costs, end of period14  
Total accumulated other comprehensive income, end of period14  
Total Shareholders’ Equity$9,806 $9,148 
Noncontrolling Interests:
Beginning of year129 142 
Net income attributable to noncontrolling interest holders1 2 
Dividends paid to noncontrolling interest holders(1)(2)
Redemptions of Ameren Illinois preferred stock (13)
Noncontrolling interests, end of period129 129 
Total Equity$9,935 $9,277 
Common stock shares outstanding at beginning of year257.7 253.3 
Shares issued under forward sale agreement 1.6 
Shares issued under the DRPlus and 401(k) plan0.1 0.1 
Shares issued for stock-based compensation0.4 0.5 
Common stock shares outstanding at end of period258.2 255.5 
Dividends per common share$0.59 $0.55 
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,
 20222021
Operating Revenues:
Electric$738 $641 
Natural gas80 63 
Total operating revenues818