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    Table of Contents                                Index to Financial Statements
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, 2021
OR
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from           to            
Commission
File Number
Registrant,
State of Incorporation,
Address and Telephone Number
I.R.S. Employer
Identification No.
1-3526 The Southern Company 58-0690070
(A Delaware Corporation)
30 Ivan Allen Jr. Boulevard, N.W.
Atlanta, Georgia 30308
(404) 506-5000
1-3164 Alabama Power Company 63-0004250
(An Alabama Corporation)
600 North 18th Street
Birmingham, Alabama 35203
(205) 257-1000
1-6468 Georgia Power Company 58-0257110
(A Georgia Corporation)
241 Ralph McGill Boulevard, N.E.
Atlanta, Georgia 30308
(404) 506-6526
001-11229 Mississippi Power Company 64-0205820
(A Mississippi Corporation)
2992 West Beach Boulevard
Gulfport, Mississippi 39501
(228) 864-1211
001-37803 Southern Power Company 58-2598670
(A Delaware Corporation)
30 Ivan Allen Jr. Boulevard, N.W.
Atlanta, Georgia 30308
(404) 506-5000
1-14174 Southern Company Gas 58-2210952
(A Georgia Corporation)
Ten Peachtree Place, N.E.
Atlanta, Georgia 30309
(404) 584-4000


    Table of Contents                                Index to Financial Statements
Securities registered pursuant to Section 12(b) of the Act:
Registrant Title of Each Class Trading
Symbol(s)
Name of Each Exchange
on Which Registered
The Southern Company Common Stock, par value $5 per share SO New York Stock Exchange
(NYSE)
The Southern Company Series 2016A 5.25% Junior Subordinated Notes due 2076 SOJB NYSE
The Southern Company Series 2017B 5.25% Junior Subordinated Notes due 2077 SOJC NYSE
The Southern Company 2019 Series A Corporate Units SOLN NYSE
The Southern Company Series 2020A 4.95% Junior Subordinated Notes due 2080 SOJD NYSE
The Southern Company Series 2020C 4.20% Junior Subordinated Notes due 2060 SOJE NYSE
Alabama Power Company 5.00% Series Class A Preferred Stock ALP PR Q NYSE
Georgia Power Company Series 2017A 5.00% Junior Subordinated Notes due 2077 GPJA NYSE
Southern Power Company Series 2016A 1.000% Senior Notes due 2022 SO/22B NYSE
Southern Power Company Series 2016B 1.850% Senior Notes due 2026 SO/26A NYSE
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 registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. Yes þ No ¨
Indicate by check mark whether the registrants have submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrants were required to submit such files). Yes þ No ¨
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.
Registrant Large Accelerated Filer Accelerated
Filer
Non-accelerated Filer Smaller
Reporting
Company
Emerging
Growth
Company
The Southern Company X
Alabama Power Company X
Georgia Power Company X
Mississippi Power Company X
Southern Power Company X
Southern Company Gas X
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.
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes No þ (Response applicable to all registrants.)
Registrant Description of Common Stock
Shares Outstanding at March 31, 2021
The Southern Company Par Value $5 Per Share 1,058,630,385 
Alabama Power Company Par Value $40 Per Share 30,537,500 
Georgia Power Company Without Par Value 9,261,500 
Mississippi Power Company Without Par Value 1,121,000 
Southern Power Company Par Value $0.01 Per Share 1,000 
Southern Company Gas Par Value $0.01 Per Share 100 
This combined Form 10-Q is separately filed by The Southern Company, Alabama Power Company, Georgia Power Company, Mississippi Power Company, Southern Power Company, and Southern Company Gas. Information contained herein relating to any individual registrant is filed by such registrant on its own behalf. Each registrant makes no representation as to information relating to the other registrants.
2

    Table of Contents                                Index to Financial Statements
TABLE OF CONTENTS
    Page
4
8
PART I—FINANCIAL INFORMATION
Item 1.
Item 2.
Item 3.
Item 4.
PART II—OTHER INFORMATION
Item 1.
Item 1A.
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds Inapplicable
Item 3. Defaults Upon Senior Securities Inapplicable
Item 4. Mine Safety Disclosures Inapplicable
Item 5. Other Information Inapplicable
Item 6.
3

    Table of Contents                                Index to Financial Statements

DEFINITIONS
Term Meaning
2019 ARP Alternate Rate Plan approved by the Georgia PSC in 2019 for Georgia Power for the years 2020 through 2022
AFUDC Allowance for funds used during construction
Alabama Power Alabama Power Company
Amended and Restated Loan Guarantee Agreement Loan guarantee agreement entered into by Georgia Power with the DOE in 2014, as amended and restated in March 2019, under which the proceeds of borrowings may be used to reimburse Georgia Power for Eligible Project Costs incurred in connection with its construction of Plant Vogtle Units 3 and 4
ARO Asset retirement obligation
Atlanta Gas Light Atlanta Gas Light Company, a wholly-owned subsidiary of Southern Company Gas
Atlantic Coast Pipeline Atlantic Coast Pipeline, LLC, a joint venture to construct and operate a natural gas pipeline in which Southern Company Gas held a 5% interest through March 24, 2020
Bechtel Bechtel Power Corporation, the primary contractor for the remaining construction activities for Plant Vogtle Units 3 and 4
Bechtel Agreement The 2017 construction completion agreement between the Vogtle Owners and Bechtel
CCR Coal combustion residuals
Chattanooga Gas Chattanooga Gas Company, a wholly-owned subsidiary of Southern Company Gas
COD Commercial operation date
Contractor Settlement Agreement The December 31, 2015 agreement between Westinghouse and the Vogtle Owners resolving disputes between the Vogtle Owners and the EPC Contractor under the Vogtle 3 and 4 Agreement
COVID-19 The novel coronavirus disease declared a pandemic by the World Health Organization and the Centers for Disease Control and Prevention in March 2020
CWIP Construction work in progress
Dalton City of Dalton, Georgia, an incorporated municipality in the State of Georgia, acting by and through its Board of Water, Light, and Sinking Fund Commissioners
Dalton Pipeline A pipeline facility in Georgia in which Southern Company Gas has a 50% undivided ownership interest
DOE U.S. Department of Energy
ECO Plan Mississippi Power's environmental compliance overview plan
Eligible Project Costs Certain costs of construction relating to Plant Vogtle Units 3 and 4 that are eligible for financing under the loan guarantee program established under Title XVII of the Energy Policy Act of 2005
EPA U.S. Environmental Protection Agency
EPC Contractor Westinghouse and its affiliate, WECTEC Global Project Services Inc.; the former engineering, procurement, and construction contractor for Plant Vogtle Units 3 and 4
FERC Federal Energy Regulatory Commission
FFB Federal Financing Bank
FFB Credit Facilities Note purchase agreements among the DOE, Georgia Power, and the FFB and related promissory notes which provide for two multi-advance term loan facilities
Fitch Fitch Ratings, Inc.
Form 10-K Annual Report on Form 10-K of Southern Company, Alabama Power, Georgia Power, Mississippi Power, Southern Power, and Southern Company Gas for the year ended December 31, 2020, as applicable
GAAP U.S. generally accepted accounting principles
Georgia Power Georgia Power Company
GRAM Atlanta Gas Light's Georgia Rate Adjustment Mechanism
Guarantee Settlement Agreement The June 9, 2017 settlement agreement between the Vogtle Owners and Toshiba related to certain payment obligations of the EPC Contractor guaranteed by Toshiba
4

    Table of Contents                                Index to Financial Statements

DEFINITIONS
(continued)
Term Meaning
Gulf Power Gulf Power Company, until January 1, 2019 a wholly-owned subsidiary of Southern Company; effective January 1, 2021, Gulf Power Company merged with and into Florida Power and Light Company, with Florida Power and Light Company remaining as the surviving company
Heating Degree Days A measure of weather, calculated when the average daily temperatures are less than 65 degrees Fahrenheit
Heating Season The period from November through March when Southern Company Gas' natural gas usage and operating revenues are generally higher
HLBV Hypothetical liquidation at book value
IGCC Integrated coal gasification combined cycle, the technology originally approved for Mississippi Power's Kemper County energy facility
IIC Intercompany Interchange Contract
IRP Integrated resource plan
ITAAC Inspections, Tests, Analyses, and Acceptance Criteria, standards established by the NRC
ITC Investment tax credit
JEA Jacksonville Electric Authority
Jefferson Island
Jefferson Island Storage and Hub, L.L.C, which owns a natural gas storage facility in Louisiana consisting of two salt dome caverns; a subsidiary of Southern Company Gas through December 1, 2020
KWH Kilowatt-hour
LIBOR London Interbank Offered Rate
LIFO Last-in, first-out
LOCOM Lower of weighted average cost or current market price
LTSA Long-term service agreement
Marketers Marketers selling retail natural gas in Georgia and certificated by the Georgia PSC
MEAG Power Municipal Electric Authority of Georgia
Mississippi Power Mississippi Power Company
Mississippi Power Rate Case Settlement Agreement Settlement agreement between Mississippi Power and the Mississippi Public
Utilities Staff approved by the Mississippi PSC in March 2020 related to Mississippi Power's base rate case filed in 2019
mmBtu Million British thermal units
Moody's Moody's Investors Service, Inc.
MRA Municipal and Rural Associations
MW Megawatt
natural gas distribution utilities Southern Company Gas' natural gas distribution utilities (Nicor Gas, Atlanta Gas Light, Virginia Natural Gas, and Chattanooga Gas)
NCCR Georgia Power's Nuclear Construction Cost Recovery
Nicor Gas Northern Illinois Gas Company, a wholly-owned subsidiary of Southern Company Gas
NRC U.S. Nuclear Regulatory Commission
NYMEX New York Mercantile Exchange, Inc.
OCI Other comprehensive income
PennEast Pipeline PennEast Pipeline Company, LLC, a joint venture to construct and operate a natural gas pipeline in which Southern Company Gas has a 20% ownership interest
PEP Mississippi Power's Performance Evaluation Plan
Pivotal LNG Pivotal LNG, Inc., through March 24, 2020, a wholly-owned subsidiary of Southern Company Gas
PowerSecure PowerSecure, Inc., a wholly-owned subsidiary of Southern Company
PowerSouth PowerSouth Energy Cooperative
PPA Power purchase agreements, as well as, for Southern Power, contracts for differences that provide the owner of a renewable facility a certain fixed price for the electricity sold to the grid
5

    Table of Contents                                Index to Financial Statements

DEFINITIONS
(continued)
Term Meaning
PSC Public Service Commission
PTC Production tax credit
Rate CNP Alabama Power's Rate Certificated New Plant, consisting of Rate CNP New Plant, Rate CNP Compliance, and Rate CNP PPA
Rate ECR Alabama Power's Rate Energy Cost Recovery
Rate RSE Alabama Power's Rate Stabilization and Equalization
Registrants Southern Company, Alabama Power, Georgia Power, Mississippi Power, Southern Power Company, and Southern Company Gas
ROE Return on equity
S&P S&P Global Ratings, a division of S&P Global Inc.
SCS Southern Company Services, Inc., the Southern Company system service company and a wholly-owned subsidiary of Southern Company
SEC U.S. Securities and Exchange Commission
SEGCO Southern Electric Generating Company, 50% owned by each of Alabama Power and Georgia Power
Sequent Sequent Energy Management, L.P. and Sequent Energy Canada Corp., wholly-owned subsidiaries of Southern Company Gas
SNG Southern Natural Gas Company, L.L.C., a pipeline system in which Southern Company Gas has a 50% ownership interest
Southern Company The Southern Company
Southern Company Gas Southern Company Gas and its subsidiaries
Southern Company Gas Capital Southern Company Gas Capital Corporation, a 100%-owned subsidiary of Southern Company Gas
Southern Company power pool The operating arrangement whereby the integrated generating resources of the traditional electric operating companies and Southern Power (excluding subsidiaries) are subject to joint commitment and dispatch in order to serve their combined load obligations
Southern Company system Southern Company, the traditional electric operating companies, Southern Power, Southern Company Gas, Southern Electric Generating Company, Southern Nuclear, SCS, Southern Communications Services, Inc., PowerSecure, and other subsidiaries
Southern Holdings Southern Company Holdings, Inc., a wholly-owned subsidiary of Southern Company
Southern Nuclear Southern Nuclear Operating Company, Inc., a wholly-owned subsidiary of Southern Company
Southern Power Southern Power Company and its subsidiaries
SouthStar SouthStar Energy Services, LLC (a Marketer), a wholly-owned subsidiary of Southern Company Gas
SP Solar SP Solar Holdings I, LP, a limited partnership indirectly owning substantially all of Southern Power's solar facilities, in which Southern Power has a 67% ownership interest
SP Wind SP Wind Holdings II, LLC, a holding company owning a portfolio of eight operating wind facilities, in which Southern Power is the controlling partner in a tax equity arrangement
Subsidiary Registrants Alabama Power, Georgia Power, Mississippi Power, Southern Power, and Southern Company Gas
Tax Reform The impact of the Tax Cuts and Jobs Act, which became effective on January 1, 2018
Toshiba Toshiba Corporation, the parent company of Westinghouse
traditional electric operating companies Alabama Power, Georgia Power, and Mississippi Power
VCM Vogtle Construction Monitoring
VIE Variable interest entity
Virginia Natural Gas Virginia Natural Gas, Inc., a wholly-owned subsidiary of Southern Company Gas
Vogtle 3 and 4 Agreement Agreement entered into with the EPC Contractor in 2008 by Georgia Power, acting for itself and as agent for the Vogtle Owners, and rejected in bankruptcy in July 2017, pursuant to which the EPC Contractor agreed to design, engineer, procure, construct, and test Plant Vogtle Units 3 and 4
6

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DEFINITIONS
(continued)
Term Meaning
Vogtle Owners Georgia Power, Oglethorpe Power Corporation, MEAG Power, and Dalton
Vogtle Services Agreement The June 2017 services agreement between the Vogtle Owners and the EPC Contractor, as amended and restated in July 2017, for the EPC Contractor to transition construction management of Plant Vogtle Units 3 and 4 to Southern Nuclear and to provide ongoing design, engineering, and procurement services to Southern Nuclear
WACOG Weighted average cost of gas
Westinghouse Westinghouse Electric Company LLC
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    Table of Contents                                Index to Financial Statements
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION
This Quarterly Report on Form 10-Q contains forward-looking statements. Forward-looking statements include, among other things, statements concerning the potential and expected effects of the COVID-19 pandemic, regulated rates, the strategic goals for the business, customer and sales growth, economic conditions, cost recovery and other rate actions, projected equity ratios, current and proposed environmental regulations and related compliance plans and estimated expenditures, pending or potential litigation matters, access to sources of capital, financing activities, completion dates and costs of construction projects, matters related to the abandonment of the Kemper IGCC, completion of announced dispositions, filings with state and federal regulatory authorities, and estimated construction plans and expenditures. In some cases, forward-looking statements can be identified by terminology such as "may," "will," "could," "would," "should," "expects," "plans," "anticipates," "believes," "estimates," "projects," "predicts," "potential," or "continue" or the negative of these terms or other similar terminology. There are various factors that could cause actual results to differ materially from those suggested by the forward-looking statements; accordingly, there can be no assurance that such indicated results will be realized. These factors include:

the impact of recent and future federal and state regulatory changes, including tax, environmental, and other laws and regulations to which Southern Company and its subsidiaries are subject, as well as changes in application of existing laws and regulations;
the potential effects of the continued COVID-19 pandemic, including, but not limited to, those described in Item 1A "Risk Factors" of the Form 10-K;
the extent and timing of costs and legal requirements related to CCR;
current and future litigation or regulatory investigations, proceedings, or inquiries, including litigation and other disputes related to the Kemper County energy facility;
the effects, extent, and timing of the entry of additional competition in the markets in which Southern Company's subsidiaries operate, including from the development and deployment of alternative energy sources;
variations in demand for electricity and natural gas;
available sources and costs of natural gas and other fuels;
the ability to complete necessary or desirable pipeline expansion or infrastructure projects, limits on pipeline capacity, and operational interruptions to natural gas distribution and transmission activities;
transmission constraints;
effects of inflation;
the ability to control costs and avoid cost and schedule overruns during the development, construction, and operation of facilities or other projects, including Plant Vogtle Units 3 and 4 (which includes components based on new technology that only within the last few years began initial operation in the global nuclear industry at this scale) and Plant Barry Unit 8, due to current and future challenges which include, but are not limited to, changes in labor costs, availability, and productivity; challenges with management of contractors or vendors; subcontractor performance; adverse weather conditions; shortages, delays, increased costs, or inconsistent quality of equipment, materials, and labor; contractor or supplier delay; delays due to judicial or regulatory action; nonperformance under construction, operating, or other agreements; operational readiness, including specialized operator training and required site safety programs; engineering or design problems; design and other licensing-based compliance matters, including, for nuclear units, inspections and the timely submittal by Southern Nuclear of the ITAAC documentation for each unit and the related reviews and approvals by the NRC necessary to support NRC authorization to load fuel; challenges with start-up activities, including major equipment failure, or system integration; and/or operational performance; and challenges related to the COVID-19 pandemic;
the ability to overcome or mitigate the current challenges at Plant Vogtle Units 3 and 4, as described in Note (B) to the Condensed Financial Statements under "Georgia Power – Nuclear Construction" in Item 1 herein, that could further impact the cost and schedule for the project;
legal proceedings and regulatory approvals and actions related to construction projects, such as Plant Vogtle Units 3 and 4, Plant Barry Unit 8, and pipeline projects, including PSC approvals and FERC and NRC actions;
under certain specified circumstances, a decision by holders of more than 10% of the ownership interests of Plant Vogtle Units 3 and 4 not to proceed with construction and the ability of other Vogtle Owners to tender a portion of their ownership interests to Georgia Power following certain construction cost increases;
8

    Table of Contents                                Index to Financial Statements
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION
(continued)
in the event Georgia Power becomes obligated to provide funding to MEAG Power with respect to the portion of MEAG Power's ownership interest in Plant Vogtle Units 3 and 4 involving JEA, any inability of Georgia Power to receive repayment of such funding;
the ability to construct facilities in accordance with the requirements of permits and licenses (including satisfaction of NRC requirements), to satisfy any environmental performance standards and the requirements of tax credits and other incentives, and to integrate facilities into the Southern Company system upon completion of construction;
investment performance of the employee and retiree benefit plans and nuclear decommissioning trust funds;
advances in technology, including the pace and extent of development of low- to no-carbon energy technologies and negative carbon concepts;
performance of counterparties under ongoing renewable energy partnerships and development agreements;
state and federal rate regulations and the impact of pending and future rate cases and negotiations, including rate actions relating to ROE, equity ratios, additional generating capacity, and fuel and other cost recovery mechanisms;
the ability to successfully operate the electric utilities' generating, transmission, and distribution facilities and Southern Company Gas' natural gas distribution and storage facilities and the successful performance of necessary corporate functions;
the inherent risks involved in operating and constructing nuclear generating facilities;
the inherent risks involved in transporting and storing natural gas;
the performance of projects undertaken by the non-utility businesses and the success of efforts to invest in and develop new opportunities;
internal restructuring or other restructuring options that may be pursued;
potential business strategies, including acquisitions or dispositions of assets or businesses, which cannot be assured to be completed or beneficial to Southern Company or its subsidiaries;
the ability of counterparties of Southern Company and its subsidiaries to make payments as and when due and to perform as required;
the ability to obtain new short- and long-term contracts with wholesale customers;
the direct or indirect effect on the Southern Company system's business resulting from cyber intrusion or physical attack and the threat of physical attacks;
interest rate fluctuations and financial market conditions and the results of financing efforts;
access to capital markets and other financing sources;
changes in Southern Company's and any of its subsidiaries' credit ratings;
changes in the method of determining LIBOR or the replacement of LIBOR with an alternative reference rate;
the ability of Southern Company's electric utilities to obtain additional generating capacity (or sell excess generating capacity) at competitive prices;
catastrophic events such as fires, earthquakes, explosions, floods, tornadoes, hurricanes and other storms, droughts, pandemic health events, political unrest, or other similar occurrences;
the direct or indirect effects on the Southern Company system's business resulting from incidents affecting the U.S. electric grid, natural gas pipeline infrastructure, or operation of generating or storage resources;
impairments of goodwill or long-lived assets;
the effect of accounting pronouncements issued periodically by standard-setting bodies; and
other factors discussed elsewhere herein and in other reports (including the Form 10-K) filed by the Registrants from time to time with the SEC.
The Registrants expressly disclaim any obligation to update any forward-looking statements.
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    Table of Contents                                Index to Financial Statements
PART I
Item 1. Financial Statements (Unaudited).
  Page
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    Table of Contents                                Index to Financial Statements

THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
 
  For the Three Months Ended March 31,
  2021 2020
  (in millions)
Operating Revenues:
Retail electric revenues $ 3,342  $ 3,078 
Wholesale electric revenues 545  418 
Other electric revenues 170  151 
Natural gas revenues (includes alternative revenue programs of $2 and $9, respectively)
1,694  1,249 
Other revenues 159  122 
Total operating revenues 5,910  5,018 
Operating Expenses:
Fuel 848  636 
Purchased power 207  181 
Cost of natural gas 583  439 
Cost of other sales 82  55 
Other operations and maintenance 1,372  1,296 
Depreciation and amortization 871  857 
Taxes other than income taxes 345  330 
Estimated loss on Plant Vogtle Units 3 and 4 48  — 
(Gain) loss on dispositions, net (44) (39)
Total operating expenses 4,312  3,755 
Operating Income 1,598  1,263 
Other Income and (Expense):
Allowance for equity funds used during construction 46  34 
Earnings from equity method investments 45  42 
Interest expense, net of amounts capitalized (450) (456)
Other income (expense), net 58  103 
Total other income and (expense) (301) (277)
Earnings Before Income Taxes 1,297  986 
Income taxes 190  145 
Consolidated Net Income 1,107  841 
Dividends on preferred stock of subsidiaries 4 
Net loss attributable to noncontrolling interests (32) (31)
Consolidated Net Income Attributable to
   Southern Company
$ 1,135  $ 868 
Common Stock Data:
Earnings per share -
Basic $ 1.07  $ 0.82 
Diluted $ 1.06  $ 0.81 
Average number of shares of common stock outstanding (in millions)
Basic 1,060  1,057 
Diluted 1,066  1,067 
The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.
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THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
 
  For the Three Months Ended March 31,
  2021 2020
  (in millions)
Consolidated Net Income $ 1,107  $ 841 
Other comprehensive income (loss):
Qualifying hedges:
Changes in fair value, net of tax of $(10) and $(30), respectively
(30) (86)
Reclassification adjustment for amounts included in net income,
   net of tax of $18 and $13, respectively
55  38 
Pension and other postretirement benefit plans:
Reclassification adjustment for amounts included in net income,
   net of tax of $1 and $2, respectively
3 
Total other comprehensive income (loss) 28  (47)
Comprehensive Income 1,135  794 
Dividends on preferred stock of subsidiaries 4 
Comprehensive loss attributable to noncontrolling interests (32) (31)
Consolidated Comprehensive Income Attributable to
   Southern Company
$ 1,163  $ 821 
The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

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    Table of Contents                                Index to Financial Statements
THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
  For the Three Months Ended March 31,
  2021 2020
  (in millions)
Operating Activities:
Consolidated net income $ 1,107  $ 841 
Adjustments to reconcile consolidated net income to net cash provided from operating activities —
Depreciation and amortization, total 964  949 
Deferred income taxes 140  (58)
Allowance for equity funds used during construction (46) (34)
Pension, postretirement, and other employee benefits (78) (67)
Settlement of asset retirement obligations (109) (86)
Stock based compensation expense 83  72 
Estimated loss on Plant Vogtle Units 3 and 4 48  — 
Storm damage accruals 54  56 
(Gain) loss on dispositions, net (41) (38)
Natural gas cost under recovery – long-term (185) — 
Other, net 114  55 
Changes in certain current assets and liabilities —
-Receivables 308  317 
-Prepayments (98) (110)
-Natural gas for sale, net of temporary LIFO liquidation 456  246 
-Natural gas cost under recovery (487) — 
-Other current assets 63  (67)
-Accounts payable (216) (504)
-Accrued taxes (212) (102)
-Accrued compensation (417) (473)
-Accrued interest (90) (60)
-Customer refunds   (103)
-Other current liabilities (116) 60 
Net cash provided from operating activities 1,242  894 
Investing Activities:
Business acquisitions, net of cash acquired (345) — 
Property additions (1,678) (1,560)
Nuclear decommissioning trust fund purchases (550) (254)
Nuclear decommissioning trust fund sales 546  249 
Proceeds from dispositions 20  982 
Cost of removal, net of salvage (85) (69)
Change in construction payables, net (116) (141)
Payments pursuant to LTSAs (60) (26)
Other investing activities 25  (70)
Net cash used for investing activities (2,243) (889)
Financing Activities:
Increase (decrease) in notes payable, net 182  (685)
Proceeds —
Long-term debt 2,150  2,653 
Common stock 14  52 
Short-term borrowings 325  565 
Redemptions and repurchases —
Long-term debt (384) (1,481)
Short-term borrowings (25) (100)
Capital contributions from noncontrolling interests 313  16 
Distributions to noncontrolling interests (46) (48)
Payment of common stock dividends (678) (655)
Other financing activities (117) (132)
Net cash provided from financing activities 1,734  185 
Net Change in Cash, Cash Equivalents, and Restricted Cash 733  190 
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period 1,068  1,978 
Cash, Cash Equivalents, and Restricted Cash at End of Period $ 1,801  $ 2,168 
Supplemental Cash Flow Information:
Cash paid (received) during the period for —
Interest (net of $21 and $20 capitalized for 2021 and 2020, respectively)
$ 519  $ 490 
Income taxes, net (51) (16)
Noncash transactions —
Accrued property additions at end of period 872  733 
Contributions from noncontrolling interests 89  — 
Contributions of wind turbine equipment 82  17 
Right-of-use assets obtained under leases 76  28 
The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.
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    Table of Contents                                Index to Financial Statements
THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
 
Assets At March 31, 2021 At December 31, 2020
  (in millions)
Current Assets:
Cash and cash equivalents $ 1,770  $ 1,065 
Receivables —
Customer accounts 1,716  1,753 
Energy marketing 412  516 
Unbilled revenues 544  672 
Other accounts and notes 478  512 
Accumulated provision for uncollectible accounts (124) (118)
Materials and supplies 1,504  1,478 
Fossil fuel for generation 494  550 
Natural gas for sale 197  460 
Prepaid expenses 657  276 
Assets from risk management activities, net of collateral 100  147 
Regulatory assets – asset retirement obligations 214  214 
Natural gas cost under recovery 487  — 
Other regulatory assets 788  810 
Other current assets 232  282 
Total current assets 9,469  8,617 
Property, Plant, and Equipment:
In service 111,579  110,516 
Less: Accumulated depreciation 32,887  32,397 
Plant in service, net of depreciation 78,692  78,119 
Nuclear fuel, at amortized cost 820  818 
Construction work in progress 9,525  8,697 
Total property, plant, and equipment 89,037  87,634 
Other Property and Investments:
Goodwill 5,280  5,280 
Nuclear decommissioning trusts, at fair value 2,346  2,303 
Equity investments in unconsolidated subsidiaries 1,368  1,362 
Other intangible assets, net of amortization of $339 and $328, respectively
477  487 
Leveraged leases 562  556 
Miscellaneous property and investments 463  398 
Total other property and investments 10,496  10,386 
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization 1,821  1,802 
Deferred charges related to income taxes 803  796 
Unamortized loss on reacquired debt 274  280 
Regulatory assets – asset retirement obligations, deferred 4,966  4,934 
Other regulatory assets, deferred 7,263  7,198 
Other deferred charges and assets 1,264  1,288 
Total deferred charges and other assets 16,391  16,298 
Total Assets $ 125,393  $ 122,935 
The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

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    Table of Contents                                Index to Financial Statements
THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
 
Liabilities and Stockholders' Equity At March 31, 2021 At December 31, 2020
  (in millions)
Current Liabilities:
Securities due within one year $ 3,535  $ 3,507 
Notes payable 1,092  609 
Energy marketing trade payables 475  494 
Accounts payable 2,058  2,312 
Customer deposits 470  487 
Accrued taxes —
Accrued income taxes 71  130 
Other accrued taxes 412  699 
Accrued interest 423  513 
Accrued compensation 584  1,025 
Asset retirement obligations 642  585 
Operating lease obligations 244  241 
Other regulatory liabilities 462  509 
Other current liabilities 1,118  968 
Total current liabilities 11,586  12,079 
Long-term Debt 46,727  45,073 
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes 8,839  8,175 
Deferred credits related to income taxes 5,676  5,767 
Accumulated deferred ITCs 2,214  2,235 
Employee benefit obligations 2,091  2,213 
Operating lease obligations, deferred 1,652  1,611 
Asset retirement obligations, deferred 10,043  10,099 
Accrued environmental remediation 208  216 
Other cost of removal obligations 2,215  2,211 
Other regulatory liabilities, deferred 226  251 
Other deferred credits and liabilities 557  480 
Total deferred credits and other liabilities 33,721  33,258 
Total Liabilities 92,034  90,410 
Redeemable Preferred Stock of Subsidiaries 291  291 
Total Stockholders' Equity (See accompanying statements)
33,068  32,234 
Total Liabilities and Stockholders' Equity $ 125,393  $ 122,935 
The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.
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    Table of Contents                                Index to Financial Statements
SOUTHERN COMPANY AND SUBSIDIARY COMPANIES
CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED)
Southern Company Common Stockholders' Equity
  Number of
Common Shares
Common Stock Accumulated
Other
Comprehensive Income
(Loss)
  Issued Treasury Par Value Paid-In Capital Treasury Retained Earnings Noncontrolling Interests Total
  (in millions)
Balance at December 31, 2019 1,054  (1) $ 5,257  $ 11,734  $ (42) $ 10,877  $ (321) $ 4,254  $ 31,759 
Consolidated net income (loss) —  —  —  —  —  868  —  (31) 837 
Other comprehensive income (loss) —  —  —  —  —  —  (47) —  (47)
Stock issued —  43  —  —  —  —  52 
Stock-based compensation —  —  —  —  —  —  — 
Cash dividends of $0.62 per share
—  —  —  —  —  (655) —  —  (655)
Capital contributions from
   noncontrolling interests
—  —  —  —  —  —  —  16  16 
Distributions to noncontrolling interests —  —  —  —  —  —  —  (48) (48)
Other —  —  —  —  (2) (2) —  (3)
Balance at March 31, 2020 1,057  (1) $ 5,266  $ 11,782  $ (44) $ 11,088  $ (367) $ 4,191  $ 31,916 
Balance at December 31, 2020 1,058  (1) $ 5,268  $ 11,834  $ (46) $ 11,311  $ (395) $ 4,262  $ 32,234 
Consolidated net income (loss)           1,135    (32) 1,103 
Other comprehensive income             28    28 
Stock issued 2    5  9          14 
Stock-based compensation       9          9 
Cash dividends of $0.64 per share
          (678)     (678)
Capital contributions from
   noncontrolling interests
              403  403 
Distributions to noncontrolling interests               (46) (46)
Other       2        (1) 1 
Balance at March 31, 2021 1,060  (1) $ 5,273  $ 11,854  $ (46) $ 11,768  $ (367) $ 4,586  $ 33,068 
The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

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ALABAMA POWER COMPANY
CONDENSED STATEMENTS OF INCOME (UNAUDITED)
 
For the Three Months Ended March 31,
  2021 2020
  (in millions)
Operating Revenues:
Retail revenues $ 1,352  $ 1,205 
Wholesale revenues, non-affiliates 92  56 
Wholesale revenues, affiliates 32  19 
Other revenues 83  71 
Total operating revenues 1,559  1,351 
Operating Expenses:
Fuel 291  215 
Purchased power, non-affiliates 50  40 
Purchased power, affiliates 30  18 
Other operations and maintenance 361  350 
Depreciation and amortization 211  200 
Taxes other than income taxes 103  106 
Total operating expenses 1,046  929 
Operating Income 513  422 
Other Income and (Expense):
Allowance for equity funds used during construction 12  10 
Interest expense, net of amounts capitalized (84) (88)
Other income (expense), net 32  24 
Total other income and (expense) (40) (54)
Earnings Before Income Taxes 473  368 
Income taxes 110  84 
Net Income 363  284 
Dividends on Preferred Stock 4 
Net Income After Dividends on Preferred Stock $ 359  $ 280 


CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
 
For the Three Months Ended March 31,
  2021 2020
  (in millions)
Net Income $ 363  $ 284 
Other comprehensive income (loss):
Qualifying hedges:
Reclassification adjustment for amounts included in net income,
   net of tax of $— and $—, respectively
1 
Total other comprehensive income (loss) 1 
Comprehensive Income $ 364  $ 285 
The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.
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    Table of Contents                                Index to Financial Statements
ALABAMA POWER COMPANY
CONDENSED STATEMENTS OF CASH FLOWS (UNAUDITED)
 
  For the Three Months Ended March 31,
  2021 2020
  (in millions)
Operating Activities:
Net income $ 363  $ 284 
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total 248  241 
Deferred income taxes 33  10 
Pension, postretirement, and other employee benefits (29) (25)
Settlement of asset retirement obligations (49) (46)
Other, net (15) 10 
Changes in certain current assets and liabilities —
-Receivables 40  93 
-Fossil fuel stock 38  (15)
-Prepayments (73) (80)
-Materials and supplies (4) (22)
-Other current assets (11) (14)
-Accounts payable (299) (305)
-Accrued taxes 104  100 
-Accrued compensation (105) (111)
-Retail fuel cost over recovery (18) 47 
-Other current liabilities (9) (12)
Net cash provided from operating activities 214  155 
Investing Activities:
Property additions (466) (340)
Nuclear decommissioning trust fund purchases (310) (81)
Nuclear decommissioning trust fund sales 310  81 
Cost of removal, net of salvage (23) (15)
Change in construction payables 32  (65)
Other investing activities (9) (4)
Net cash used for investing activities (466) (424)
Financing Activities:
Redemptions — Pollution control revenue bonds   (87)
Capital contributions from parent company 600  610 
Payment of common stock dividends (246) (239)
Other financing activities (13) (11)
Net cash provided from financing activities 341  273 
Net Change in Cash, Cash Equivalents, and Restricted Cash 89 
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period 530  894 
Cash, Cash Equivalents, and Restricted Cash at End of Period $ 619  $ 898 
Supplemental Cash Flow Information:
Cash paid during the period for —
Interest (net of $3 capitalized for both 2021 and 2020)
$ 93  $ 92 
Noncash transactions —
Accrued property additions at end of period 198  135 
Right-of-use assets obtained under leases 1 
The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.
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    Table of Contents                                Index to Financial Statements
ALABAMA POWER COMPANY
CONDENSED BALANCE SHEETS (UNAUDITED)
 
Assets At March 31, 2021 At December 31, 2020
(in millions)
Current Assets:
Cash and cash equivalents $ 619  $ 530 
Receivables —
Customer accounts 394  429 
Unbilled revenues 124  152 
Affiliated 35  31 
Other accounts and notes 71  66 
Accumulated provision for uncollectible accounts (33) (43)
Fossil fuel stock 197  235 
Materials and supplies 550  546 
Prepaid expenses 114  42 
Other regulatory assets 224  226 
Other current assets 43  33 
Total current assets 2,338  2,247 
Property, Plant, and Equipment:
In service 32,015  31,816 
Less: Accumulated provision for depreciation 10,123  10,009 
Plant in service, net of depreciation 21,892  21,807 
Nuclear fuel, at amortized cost 268  270 
Construction work in progress 1,052  866 
Total property, plant, and equipment 23,212  22,943 
Other Property and Investments:
Nuclear decommissioning trusts, at fair value 1,198  1,157 
Equity investments in unconsolidated subsidiaries 63  63 
Miscellaneous property and investments 128  131 
Total other property and investments 1,389  1,351 
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization 140  151 
Deferred charges related to income taxes 237  235 
Regulatory assets – asset retirement obligations 1,446  1,441 
Other regulatory assets, deferred 2,161  2,162 
Other deferred charges and assets 282  273 
Total deferred charges and other assets 4,266  4,262 
Total Assets $ 31,205  $ 30,803 
The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.

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    Table of Contents                                Index to Financial Statements
ALABAMA POWER COMPANY
CONDENSED BALANCE SHEETS (UNAUDITED)
 
Liabilities and Stockholder's Equity At March 31, 2021 At December 31, 2020
  (in millions)
Current Liabilities:
Securities due within one year $ 815  $ 311 
Accounts payable —
Affiliated 220  316 
Other 392  545 
Customer deposits 105  104 
Accrued taxes 257  152 
Accrued interest 75  90 
Accrued compensation 113  212 
Asset retirement obligations 275  254 
Other regulatory liabilities 98  108 
Other current liabilities 108  107 
Total current liabilities 2,458  2,199 
Long-term Debt 8,055  8,558 
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes 3,318  3,273 
Deferred credits related to income taxes 2,006  2,016 
Accumulated deferred ITCs 92  94 
Employee benefit obligations 187  214 
Operating lease obligations 112  119 
Asset retirement obligations, deferred 3,688  3,720 
Other cost of removal obligations 320  335 
Other regulatory liabilities, deferred 98  124 
Other deferred credits and liabilities 54  50 
Total deferred credits and other liabilities 9,875  9,945 
Total Liabilities 20,388  20,702 
Redeemable Preferred Stock 291  291 
Common Stockholder's Equity (See accompanying statements)
10,526  9,810 
Total Liabilities and Stockholder's Equity $ 31,205  $ 30,803 
The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.
20

    Table of Contents                                Index to Financial Statements
ALABAMA POWER COMPANY
CONDENSED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY (UNAUDITED)
Number of
Common
Shares
Issued
Common
Stock
Paid-In
Capital
Retained
Earnings
Accumulated
Other
Comprehensive
Income (Loss)
Total
(in millions)
Balance at December 31, 2019 31  $ 1,222  $ 4,755  $ 3,001  $ (23) $ 8,955 
Net income after dividends on
   preferred stock
—  —  —  280  —  280 
Capital contributions from parent company —  —  612  —  —  612 
Other comprehensive income —  —  —  — 
Cash dividends on common stock —  —  —  (239) —  (239)
Balance at March 31, 2020 31  $ 1,222  $ 5,367  $ 3,042  $ (22) $ 9,609 
Balance at December 31, 2020 31  $ 1,222  $ 5,413  $ 3,194  $ (19) $ 9,810 
Net income after dividends on
   preferred stock
      359    359 
Capital contributions from parent company     602      602 
Other comprehensive income