SOUTHERN CO

Southern Company Gas has various regulatory mechanisms, such as weather and revenue normalization and straight-fixed-variable rate design, which limit its exposure to weather changes within typical ranges in each of its utility's respective service territory. Southern Company Gas also utilizes weather hedges to limit the negative income impacts in the event of warmer-than-normal weather in Illinois for gas distribution operations and in Illinois and Georgia for gas marketing services. Therefore, weather typically does not have a significant net income impact.

During the Heating Season, natural gas usage and operating revenues are generally higher as more customers are connected to the gas distribution systems and natural gas usage is higher in periods of colder weather. Southern Company Gas' base operating expenses, excluding cost of natural gas and bad debt expense, are incurred relatively evenly throughout the year. Seasonality also affects the comparison of certain balance sheet items across quarters, including receivables, unbilled revenues, natural gas for sale, and notes payable. However, these items are comparable when reviewing Southern Company Gas' annual results. Thus, Southern Company Gas' operating results can vary significantly from quarter to quarter as a result of seasonality, which is illustrated in the table below.

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Net Income

Net income attributable to Southern Company Gas in 2023 was $615 million, an increase of $43 million, or 7.5%, compared to 2022. Net income increased primarily as a result of an impairment charge in 2022 related to the sale of natural gas storage facilities. The increase in net income was partially offset by a decrease of $29 million in net income at gas distribution operations primarily as a result of reduced revenue due to lower volumes sold, regulatory disallowances at Nicor Gas, and higher depreciation related to continued investment in infrastructure replacement programs, partially offset by lower cost of gas, and a $9 million decrease in net income at gas pipeline investments primarily as a result of higher expenses at SNG.

A condensed income statement for Southern Company Gas follows:

Operating revenues in 2023 were $4.7 billion, reflecting a $1.3 billion, or 21.1%, decrease compared to 2022. Details of operating revenues were as follows:

Revenues from infrastructure replacement programs and base rate changes increased in 2023 primarily due to rate increases at the natural gas distribution utilities and continued investment in infrastructure replacement, partially offset by lower volumes sold and regulatory disallowances at Nicor Gas. See Note 2 to the financial statements under "Southern Company Gas" for additional information.

Revenues associated with gas costs and other cost recovery decreased in 2023 primarily due to lower natural gas cost recovery associated with lower natural gas prices, the timing of natural gas purchases, and the recovery of those costs from customers. The natural gas distribution utilities have weather or revenue normalization mechanisms that mitigate revenue fluctuations from

II-35 customer consumption changes. Natural gas distribu tion rates include provisions to adjust billings for fluctuations in natural gas costs. Therefore, gas costs recovered through natural gas revenues generally equal the amount expensed in cost of natural gas and do not affect net income from gas distribution operations. See "Cost of Natural Gas" herein for additional information.

Revenues from gas marketing services decreased in 2023 primarily due to lower natural gas prices and the timing of unrealized hedge losses.

Customer Count

The number of customers served by gas distribution operations and gas marketing services can be impacted by natural gas prices, economic conditions, and competition from alternative fuels. Gas distribution operations' and gas marketing services' customers are primarily located in Georgia and Illinois.

The following table provides the number of customers served by Southern Company Gas at December 31, 2023 and 2022:

Southern Company Gas anticipates customer growth and uses a variety of targeted marketing programs to attract new customers and to retain existing customers.

Excluding Atlanta Gas Light, which does not sell natural gas to end-use customers, natural gas distribution rates include provisions to adjust billings for fluctuations in natural gas costs. Therefore, gas costs recovered through natural gas revenues generally equal the amount expensed in cost of natural gas and do not affect net income from gas distribution operations. See Note 2 to the financial statements under "Southern Company Gas –Natural Gas Cost Recovery" for additional information. Cost of natural gas at gas distribution operations repr esented 83.5% of the total cost of natural gas for 2023.

Gas marketing services customers are charged for actual and estimated natural gas consumed. Cost of natural gas includes the cost of fuel and associated transportation costs, lost and unaccounted for gas, and gains and losses associated with certain derivatives.

In 2023, cost of natural gas was $1.6 billion, a decrease of $1.4 billion, or 45.3%, compared to 2022, which reflects lower gas cost recovery in 2023 as a result of a 58.8% decrease in natural gas prices compared to 2022.

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Volumes of Natural Gas Sold

Southern Company Gas' natural gas volume metrics for gas distribution operations and gas marketing services illustrate the effects of weather and customer demand for natural gas.

The following table details the volumes of natural gas sold during all periods presented:

In 2023, other operations and maintenance expenses increased $18 million, or 1.5%, compared to 2022. The increase was primarily due to increases of $70 million in compensation and benefits and $20 million related to energy service contracts, partially offset by a decrease of $60 million in expenses passed through to customers primarily related to bad debt and energy efficiency programs at gas distribution operations. See Note 2 to the financial statements under "Southern Company Gas" for additional information.

In 2023, depreciation and amortization increased $23 million, or 4.1%, compared to 2022. The increase was primarily due to continued infrastructure investments at the natural gas distribution utilities. See Note 2 to the financial statements under "Southern Company Gas – Infrastructure Replacement Programs and Capital Projects" for additional information.

In 2023, taxes other than income taxes decreased $20 million, or 7.1%, compared to 2022. The decrease was primarily due to a $29 million decrease in revenue taxes, partially offset by increases in payroll and property taxes.

In 2022, Southern Company Gas recorded pre-tax impairment charges totaling approximately $131 million ($99 million after tax) as a result of an agreement to sell two natural gas storage facilities. See Note 15 to the financial statements under "Southern Company Gas" for additional information.

Estimated Loss on Regulatory Disallowance

In 2023, Southern Company Gas recorded pre-tax charges related to the disallowance of certain capital investments at Nicor Gas, $88 million of which was recorded in estimated loss on regulatory disallowance. See Note 2 under "Southern Company Gas – Infrastructure Replacement Programs and Capital Projects – Nicor Gas" for additional information.

In 2023, interest expense, net of amounts capitalized increased $47 million, or 17.9%, compared to 2022. The increase reflects $43 million related to higher interest rates and $8 million related to higher average outstanding borrowings. See Note 8 to the financial statements for additional information.

In 2023, income taxes increased $31 million, or 17.2%, compared to 2022. The increase was primarily due to $33 million of tax benefit in 2022 related to the impairment charges associated with the sale of two natural gas storage facilities and higher taxes

II-37 related to increased earnings, partially offset by approximately $24 million related to the regulatory disallowances at Nicor Gas. See Notes 2 and 15 to the financial statements under "Southern Company Gas" and Note 10 to the financial statements for additional information.

Segment Information

Gas distribution operations is the largest component of Southern Company Gas' business and is subject to regulation and oversight by regulatory agencies in each of the states it serves. These agencies approve natural gas rates designed to provide Southern Company Gas with the opportunity to generate revenues to recover the cost of natural gas delivered to its customers and its fixed and variable costs, including depreciation, interest expense, operations and maintenance, taxes, and overhead costs, and to earn a reasonable return on its investments.

With the exception of Atlanta Gas Light, Southern Company Gas' second largest utility that operates in a deregulated natural gas market and has a straight-fixed-variable rate design that minimizes the variability of its revenues based on consumption, the earnings of the natural gas distribution utilities can be affected by customer consumption patterns that are a function of weather conditions, price levels for natural gas, and general economic conditions that may impact customers' ability to pay for natural gas consumed. Southern Company Gas has various regulatory and other mechanisms, such as weather and revenue normalization mechanisms and weather derivative instruments, that limit its exposure to changes in customer consumption, including weather changes within typical ranges in its natural gas distribution utilities' service territories. See Note 2 to the financial statements under "Southern Company Gas" for additional information.

In 2023, net income decreased $29 million, or 6.2%, compared to 2022. Operating revenues decreased $1.2 billion primarily due to lower gas cost recovery and lower volumes sold, partially offset by rate increases and continued investment in infrastructure replacement. Gas costs recovered through natural gas revenues generally equal the amount expensed in cost of natural gas. Operating expenses decreased $1.2 billion primarily due to a $1.3 billion decrease in the cost of natural gas as a result of lower gas prices compared to 2022 and lower taxes other than income taxes, partially offset by $88 million related to the regulatory disallowances at Nicor Gas, higher depreciation resulting from additional assets placed in service, higher compensation and benefits expenses, and a $20 million increase related to energy service contracts. The decrease in operating expenses also includes costs passed through directly to customers, primarily related to bad debt expenses, energy efficiency programs, and revenue taxes. The decrease in net income also includes an increase of $46 million in interest expense, net of amounts capitalized primarily due to higher interest rates and higher average outstanding debt, partially offset by a $19 million decrease in income taxes primarily as a result of the tax benefit resulting from the regulatory disallowances at Nicor Gas. See Note 2 to the financial statements under "Southern Company Gas" for additional information.

Gas Pipeline Investments

Gas pipeline investments consists primarily of joint ventures in natural gas pipeline investments including SNG and Dalton Pipeline. In 2023, net income decreased $9 million compared to 2022. The decrease was primarily due to lower earnings at SNG resulting from higher expenses. See Note 7 to the financial statements under "Southern Company Gas" for additional information.

Gas marketing services provides energy-related products and services to natural gas markets and participants in customer choice programs that were approved in various states to increase competition. These programs allow customers to choose their natural gas supplier while the local distribution utility continues to provide distribution and transportation services. Gas marketing

II-38 services is weather sensitive and uses a variety of hedging strategies, such as weather derivative instruments and other risk management tools, to partially mitigate potential weather impacts.

In 2023, net income decreased $3 million, or 3.2%, compared to 2022. The decrease was due to a $90 million decrease in operating revenues primarily due to lower gas prices and the timing of unrealized hedge losses, largely offset by an $87 million decrease in operating expenses primarily related to a $106 million decrease in cost of gas, partially offset by higher compensation and benefits.

All Other

All other includes natural gas storage businesses, a renewable natural gas business, AGL Services Company, and Southern Company Gas Capital, as well as various corporate operating expenses that are not allocated to the reportable segments and interest income (expense) associated with affiliate financing arrangements. All other included a natural gas storage facility in Texas through its sale in November 2022 and a natural gas storage facility in California through its sale in September 2023. See Note 15 to the financial statements under "Southern Company Gas" for additional information.

In 2023, net income increased $84 million compared to 2022. The increase was primarily due to a decrease in operating expenses primarily related to pre-tax impairment charges in 2022 totaling approximately $131 million ($99 million after tax) as a result of an agreement to sell two natural gas storage facilities, lower depreciation, lower cost of gas, and lower taxes other than income taxes, partially offset by a decrease in operating revenues of $19 million and an increase in income taxes. See Note 10 to the financial statements and Note 15 to the financial statements under "Southern Company Gas" for additional information.