You should read the following discussion together with our consolidated financial statements and the related notes thereto which appear elsewhere in this annual report. We prepare our consolidated financial statements in accordance with IFRS Accounting Standards as issued by the IASB. In addition, you should read carefully notes 2(4) and 3 of the notes to our consolidated financial statements which provide summaries of certain critical accounting estimates that require our management to make difficult, complex or subjective judgments relating to matters which are highly uncertain and that may have a material impact on our financial conditions and results of operations. 50 Table of Contents Item 5.A. Operating Results Overview Our operations are reported in three segments: (1) cellular services, which include wireless voice and data transmission services, sales of wireless devices, cellular interconnection services, and various other solutions and services including certain new growth businesses and other miscellaneous cellular services, (2) fixed-line telecommunication services, which include fixed-line telephone services, broadband Internet services, advanced media platform services (including IPTV and cable TV services), and business communications and related infrastructure services, and (3) other businesses, which include our T-commerce business and certain other miscellaneous businesses that do not meet the quantitative thresholds to be separately considered reportable segments. In our cellular services segment, we earn revenue principally from our wireless voice and data transmission services through monthly plan-based fees, usage charges for outgoing voice calls, usage charges for wireless data services and value-added service fees paid by our wireless subscribers as well as interconnection fees paid to us by other telecommunications operators for use of our wireless network by their customers and subscribers. We also derive revenue from sales of wireless devices by PS&Marketing. Other sources of revenue include revenue from our other miscellaneous cellular services and our new services and products utilizing our AI and digital infrastructure capabilities and our telecommunications platforms, including a broad range of IoT solutions and enterprise communications services, cloud services, subscription services, advertising and curated shopping services, AI B2C services and AI B2B services. In our fixed-line telecommunication services segment, we earn revenue principally from our fixed-line telephone services and broadband Internet services and advanced media platform services (including IPTV and cable TV services) through monthly plan-based fees and usage charges as well as interconnection fees paid to us by other telecommunications operators for use of our fixed-line network by their customers and subscribers, and advertising fees paid to us by businesses that advertise their products and services on our advanced media platforms. In addition, we derive revenue from international calling services and our business communications and related infrastructure services through customized fee arrangements with our business customers. In our others segment, we have principally earned revenue from the T-commerce business of SK Stoa, which derives revenue through third-party seller fees earned (including commissions) for transactions in which it acts as a selling agent on SK stoa, its T-commerce network. In December 2025, we entered into an agreement to sell our entire equity stake in SK Stoa and Media S, which operates two TV channels and co-produces original television entertainment contents, to Rapport Labs Inc., a Korea-based e-commerce company, as part of our ongoing strategy to streamline and optimize our overall business portfolio. Such transaction is currently pending subject to regulatory approval and other customary closing conditions, and the assets and liabilities of SK Stoa and Media S are classified as assets and liabilities held for sale in our consolidated financial statements included in this annual report. Prior to the completion of the disposal transactions described below, we also derived revenue from online portal services under our “Nate” brand name through our former subsidiary NATE Communications Corporation, and online corporate employment benefits management and training services for Korean businesses and public institutions through our former indirect subsidiary SK M&Service. See “— Operational Efficiency.” Our cellular service revenue and fixed-line telecommunications service revenue depend principally upon the number of our subscribers and service users, the rates we charge for our services, the frequency and volume of subscriber usage of our services and the terms of our interconnection with other telecommunications operators. Our others revenue depends principally upon the gross merchandise volume, which is the total monetary value of customer purchases of goods and services, net of estimated refunds, of SK stoa and the number of merchants that utilize SK stoa to advertise and promote their products and services and the extent of such advertisement and promotion. 51 Table of Contents Among other factors, management uses operating profit of each reportable segment presented in accordance with K-IFRS (“segment operating profit”) in its assessment of the profitability of each reportable segment. The sum of segment operating profit for all three reportable segments differs from our operating profit presented in accordance with IFRS Accounting Standards as issued by the IASB as segment operating profit does not include certain items such as donations, gain and loss from disposal of property and equipment and intangible assets and impairment loss on property and equipment and intangible assets. For a reconciliation of operating profit presented in accordance with IFRS Accounting Standards as issued by the IASB and operating profit presented in accordance with K-IFRS, see “— Explanatory Note Regarding Presentation of Certain Financial Information under K-IFRS.” In addition to the information set forth below, see note 4 of the notes to our consolidated financial statements for more detailed information regarding each of our reportable segments. A number of recent developments have had or are expected to have a material impact on our results of operations, financial condition and capital expenditures. These developments include: Rate Regulations. Under the MDDIA, wireless telecommunications service providers were obliged to provide certain benefits, such as discounted rates, to subscribers who subscribe to their service without receiving handset subsidies. Handset subsidies are provided to subscribers who agree to use our service for a predetermined service period and purchase handsets on an installment basis. In June 2017, the State Affairs Planning Advisory Committee of Korea announced that it would encourage wireless telecommunications service providers, including us, to increase the applicable discount rate offered to subscribers from 20% to 25%, which we adopted in September 2017, and to offer additional discounts to low income customers, including those on government welfare programs and senior citizen recipients of the basic pension, which we implemented in December 2017 and July 2018, respectively. Although the MDDIA was repealed in July 2025, discounted rates offered under the MDDIA have been retained through a related amendment to the Telecommunications Business Act. See “Item 4.B. Business Overview — Law and Regulation — Rate Regulation.” These Government measures have adversely affected our revenues and results of operations as more subscribers elected to receive the 25% rate discount in recent years. On the other hand, this has also led to a reduction of, or partially offset increases in, our marketing expenses as the number of subscribers who have elected to receive handset subsidies has generally declined in recent years, and has contributed to maintaining a stable churn rate. Moreover, following the abolishment of the MDDIA as discussed above, we have increased our marketing expenses relating to handset subsidies in part depending on the prevailing competitive landscape, which may have an adverse effect on our operating expenses and results of operations. Decrease in Interconnection Fees. Our wireless telecommunications services depend, in part, on our interconnection arrangements with domestic and international fixed-line and other wireless networks. Charges for interconnection affect our revenues and operating results. The MSIT determines the basic framework for interconnection arrangements, including policies relating to interconnection rates in Korea. Under our interconnection agreements, we are required to make payments in respect of calls which originate from our networks and terminate in the networks of other Korean telecommunications operators, and the other operators are required to make payments to us in respect of calls which originate in their networks and terminate in our network. The MSIT has continued to gradually decrease the interconnection rates in Korea, which has led to an overall decrease in our interconnection revenue as well as interconnection expenses from 2012 to 2025 and any further reduction in interconnection rates by the MSIT may continue to impact our results of operations. Beginning in 2017, a single interconnection rate paid by fixed-line network service providers for fixed-line to wireless calls applies to all wireless telecommunications service providers. For more information about our interconnection revenue and expenses, see “Item 4.B. Business Overview — Interconnection.” Changes in Monthly Revenue per Subscriber. We measure monthly average revenue per subscriber using two metrics: average monthly revenue per subscriber excluding MVNO subscribers leasing our networks (“ARPU”) and average monthly revenue per subscriber including such MVNO subscribers (“ARPU including MVNO”). ARPU is derived by dividing the sum of total SK Telecom revenues on a separate basis from voice 52 Table of Contents service and data service for the period (excluding revenue derived from MVNO subscribers leasing our networks) by the monthly average number of subscribers (excluding the number of MVNO subscribers) for the period, then dividing that number by the number of months in the period. ARPU including MVNO is derived by dividing the sum of total SK Telecom revenues on a separate basis from voice service and data service for the period (including revenue derived from MVNO subscribers) by the monthly average number of subscribers (including the number of MVNO subscribers) for the period, then dividing that number by the number of months in the period. Our ARPU decreased by 5.1% to Won 27,845 in 2025 from Won 29,355 in 2024, which represented a decrease of 1.7% from Won 29,874 in 2023. Our ARPU including MVNO decreased by 5.5% to Won 26,146 in 2025 from Won 27,658 in 2024, which represented a decrease of 0.8% from Won 27,887 in 2023. The decreases in ARPU and ARPU including MVNO in 2025 were both primarily due to discounts on monthly subscription fees we offered for the month of August 2025 as part of the Customer Appreciation Package following the cybersecurity incident of which we became aware in April 2025 as described above. See “— Overview — Cybersecurity.” The decrease in ARPU in 2024 was primarily due to an increase in subscriptions for secondary mobile phones and non-mobile phone devices, from which we generally derive lower revenue per subscriber, which effect was offset in part by an increase in the number of subscribers that subscribe to our 5G subscription plans. The decrease in ARPU including MVNO in 2024 was primarily due to an increase in the number of MVNO subscribers from whom we derive lower ARPU. Economic Conditions in Korea. Demand for our products and services may fluctuate in light of the overall economic conditions in Korea. The overall prospects for the Korean economy and, in turn, the market conditions for the industries in which we operate, remain uncertain, and have been affected by, among others, the COVID-19 pandemic, the Russia-Ukraine war and ensuing sanctions against Russia, difficulties faced by several banks in the United States and Europe, fluctuations in policy interest rates globally (including Korea), and more recently, the military conflicts between Iran and other countries, including the United States and Israel, have adversely affected, and may continue to adversely affect, the Korean economy. In addition, an increase in unemployment among, and/or a decrease in disposable income of, our customers resulting from mixed signs of deterioration and uncertain recovery displayed by the Korean economy as described above, may decrease demand for some of our products and services or cause an increase in delinquent subscriber accounts. See “Item 3.D. Risk Factors — Risks Relating to Korea — Unfavorable financial and economic developments in Korea may have an adverse effect on us.” Operational Efficiency. We are striving to enhance our operational efficiency through our efforts to reduce operating expenses, optimize capital expenditures and reorganize non-essential business lines and investments. For example, in order to streamline our operating expenses, we have been actively utilizing AI technology in various operational processes, including our marketing activities and customer services. Furthermore, we have shifted the focus of our 5G network-related capital expenditure from expanding network coverage and increasing maximum data transmission speed to enhancing network quality. Moreover, in December 2024, we entered into agreements with Samgu Inc. and its affiliates to dispose of a 70% equity interest in SK M&Service, as well as our 100% equity interest in our former wholly-owned subsidiary NATE Communications Corporation, which operates the “Nate” internet portal, and the entirety of our 50% equity interest in our former associate F&U Credit Information, which provides credit information services. The disposals of NATE Communications Corporation, SK M&Service and F&U Credit Information were completed in January 2025, February 2025 and April 2025, respectively. More recently, in December 2025, we entered into an agreement to sell our entire equity stake in SK Stoa, which operates our T-commerce business, and Media S, which operates two TV channels and co-produces original television entertainment contents, to Rapport Labs Inc., a Korea-based e-commerce company, as part of our ongoing strategy to streamline and optimize our overall business portfolio. Such transaction is currently pending subject to regulatory approval and other customary closing conditions, and the assets and liabilities of SK Stoa and Media S are classified as assets and liabilities held for sale in our consolidated financial statements included in this annual report. 53 Table of Contents Cybersecurity. Our business involves the storage and transmission of large amounts of personal information, and cybersecurity breaches expose us to a risk of loss of this information, which may lead to improper use or disclosure of such information, ensuing potential liability and litigation, and loss of customers, any of which could harm our reputation and adversely affect our business. We maintain a comprehensive process for assessing, identifying and managing material risks from cybersecurity threats as part of our overall risk management system and processes. On April 18, 2025, we became aware of a malware attack against our information technology infrastructure, which resulted in the leakage of certain USIM information of our 5G and LTE network subscribers. While we have addressed such incident with various remedial measures, including ongoing and planned investments in strengthening our cybersecurity and customer compensation packages, such incident resulted in a decrease in the number of our mobile phone subscribers and has had a negative impact on the average monthly churn rate of our wireless telecommunications business. In addition, on August 27, 2025, the PIPC imposed a fine of Won 134.8 billion and an administrative penalty of Won 9.6 million and issued a correctional order on us in connection with this incident. While we have provisionally paid the fine and the administrative penalty in full, we filed an administrative lawsuit challenging such decision in January 2026, which case is currently pending before the Seoul Administrative Court. See “Item 3.D. Risk Factors — Risks Relating to Our Business — Malicious and abusive Internet practices could impair our services and we may be subject to significant legal and financial exposure, damage to our reputation and a loss of confidence of our customers” and “Item 16K. Cybersecurity.” Explanatory Note Regarding Presentation of Certain Financial Information under K-IFRS In addition to preparing consolidated financial statements in accordance with IFRS Accounting Standards as issued by the IASB included in this annual report, we also prepare financial statements in accordance with Korean International Financial Reporting Standards (“K-IFRS”) as adopted by the Korean Accounting Standards Board (“KASB”), which we are required to file with the FSC and the Korea Exchange under the FSCMA. 54 Table of Contents K-IFRS requires operating profit, which is calculated as operating revenue less operating expenses, to be separately presented on the consolidated statement of income. The presentation of operating profit in our consolidated statements of income prepared in accordance with IFRS Accounting Standards as issued by the IASB included in this annual report differs from the presentation of operating profit in the consolidated statements of income prepared in accordance with K-IFRS for the corresponding periods in certain respects. The table below sets forth a reconciliation of our operating profit as presented in our consolidated statements of income prepared in accordance with IFRS Accounting Standards as issued by the IASB for each of the three years ended December 31, 2025 to the operating profit as presented in the consolidated statements of income prepared in accordance with K-IFRS. For the Year Ended December 31, 2025 2024 2023 (In billions of Won) Operating profit pursuant to IFRS Accounting Standards as issued by the IASB W 1,048.5 W 1,690.9 W 1,756.3 Differences: Other income pursuant to IFRS Accounting Standards as issued by the IASB that are classified as other non-operating income pursuant to K-IFRS: Gain on disposal of property and equipment and intangible assets (127.1 ) (37.3 ) (21.9 ) Others (43.3 ) (35.0 ) (28.5 ) (170.4 ) (72.3 ) (50.4 ) Other operating expenses pursuant to IFRS Accounting Standards as issued by the IASB that are classified as other non-operating expenses pursuant to K-IFRS: Impairment loss on property and equipment and intangible assets 3.1 94.7 10.4 Impairment loss on assets held for sale 12.3 — — Loss on disposal of property and equipment and intangible assets 15.3 17.4 9.4 Donations 15.3 15.7 14.8 Bad debt for accounts receivable – other 3.3 4.8 5.3 Others 145.8 72.2 7.5 195.1 204.8 47.3 Operating profit pursuant to K-IFRS W 1,073.2 W 1,823.4 W 1,753.2 See note 4(2) of the notes to our consolidated financial statements. However, there is no impact on profit for the year or earnings per share for each of the three years ended December 31, 2025, 2024 and 2023. 55 Table of Contents Operating Results The following table sets forth summary consolidated statement of income information, including that expressed as a percentage of operating revenue and other income, for the periods indicated: For the year ended December 31, 2025 2024 2023 (In billions of Won, except percentages) Operating revenue and other income W 17,269.6 100.0 % W 18,012.9 100.0 % W 17,658.9 100.0 % Revenue 17,099.2 99.0 17,940.6 99.6 17,608.5 99.7 Other income 170.4 1.0 72.3 0.4 50.4 0.3 Operating expenses 16,221.1 93.9 16,322.0 90.6 15,902.6 90.1 Operating profit 1,048.5 6.1 1,690.9 9.4 1,756.3 9.9 Profit before income tax 722.3 4.2 1,761.8 9.8 1,488.2 8.4 Income tax expense 347.2 2.0 374.7 2.1 342.2 1.9 Profit for the year 375.1 2.2 1,387.1 7.7 1,145.9 6.5 Attributable to: Owners of the Parent Company 408.4 2.4 1,250.2 6.9 1,093.6 6.2 Non-controlling interests (33.3 ) (0.2 ) 136.9 0.8 52.3 0.3 The following table sets forth additional information about our operations with respect to our reportable segments during the periods indicated: For the year ended December 31, 2025 2024 2023 Amount Percentage of Total Revenue Amount Percentage of Total Revenue Amount Percentage of Total Revenue (In billions of Won, except percentages) Cellular Services Revenue Wireless Service(1) W 9,715.6 56.8 % W 10,401.6 58.0 % W 10,329.0 58.7 % Cellular Interconnection 369.9 2.2 400.5 2.2 432.7 2.5 Wireless Device Sales 1,034.7 6.1 1,078.7 6.0 993.9 5.6 Miscellaneous(2) 1,432.3 8.4 1,437.4 8.0 1,367.6 7.8 Total Cellular Services Revenue 12,552.5 73.4 13,318.2 74.2 13,123.2 74.5 Fixed-line Telecommunication Services Revenue Fixed-line Telephone Service 142.5 0.8 156.5 0.9 147.7 0.8 Fixed-line Interconnection 12.4 0.1 14.0 0.1 15.8 0.1 Broadband Internet Service and Advanced Media Platform Service(3) 2,508.1 14.7 2,510.3 14.0 2,494.0 14.2 International Calling Service 200.9 1.2 213.7 1.2 190.9 1.1 Miscellaneous(4) 1,327.2 7.8 1,180.9 6.6 1,079.6 6.1 Total Fixed-line Telecommunication Services Revenue 4,191.1 24.5 4,075.4 22.7 3,928.0 22.3 Others Revenue T-commerce(5) 312.9 1.8 302.3 1.7 301.3 1.7 Portal Service(6) — — 21.3 0.1 23.2 0.1 Miscellaneous(7) 42.7 0.2 223.4 1.2 232.8 1.3 Total Others Revenue 355.6 2.1 547.0 3.0 557.3 3.2 Total Revenue 17,099.2 100.0 17,940.6 100.0 17,608.5 100.0 56 Table of Contents For the year ended December 31, 2025 2024 2023 Amount Percentage of Total Revenue Amount Percentage of Total Revenue Amount Percentage of Total Revenue (In billions of Won, except percentages) Segment Operating Expenses(8) Cellular Services 11,808.3 69.1 11,746.3 65.5 11,673.1 66.3 Fixed-line Telecommunication Services 3,834.8 22.4 3,754.7 20.9 3,582.1 20.3 Others 382.9 2.2 616.2 3.4 600.1 3.4 Total Segment Operating Expenses 16,026.0 93.7 16,117.2 89.8 15,855.3 90.0 Segment Operating Profit (Loss) (9) Cellular Services 744.2 4.4 1,571.9 8.8 1,450.1 8.2 Fixed-line Telecommunication Services 356.3 2.1 320.7 1.8 345.9 2.0 Others (27.3 ) (0.2 ) (69.2 ) (0.4 ) (42.8 ) (0.2 ) Total Segment Operating Profit W 1,073.2 6.3 % W 1,823.4 10.2 % W 1,753.2 10.0 % (1) Wireless service revenue includes revenue from wireless voice and data transmission services principally derived through monthly plan-based fees, usage charges for outgoing voice calls, usage charges for wireless data services and value-added service fees such as fees for T Universe subscription program paid by wireless subscribers. (2) Miscellaneous cellular services revenue includes revenue from our IoT and other solutions as well as other miscellaneous cellular services. (3) Broadband internet service and advanced media platform service revenue includes revenues from our broadband Internet services as well as IPTV and cable TV services. (4) Miscellaneous fixed-line telecommunication services revenue includes revenues from business communications and related infrastructure services (other than fixed-line telephone service) provided by SK Broadband. (5) T-commerce services revenue includes revenues from SK Stoa. In December 2025, we entered into an agreement to sell our entire equity stake in SK Stoa and Media S to Rapport Labs Inc., a Korea-based e-commerce company. Such transaction is currently pending subject to regulatory approval and other customary closing conditions, and the assets and liabilities of SK Stoa and Media S are classified as assets and liabilities held for sale in our consolidated financial statements included in this annual report. See “— Overview — Operational Efficiency.” (6) Portal service revenue includes revenues from our former subsidiary NATE Communications Corporation. See “— Overview — Operational Efficiency.” (7) Miscellaneous revenue includes revenues from our former indirect subsidiary SK M&Service and other minor miscellaneous revenue items. See “— Overview — Operational Efficiency.” (8) “Segment operating expenses” mean operating expenses for each reportable segment presented in accordance with K-IFRS and therefore does not include certain expenses that are classified as other non-operating expenses under K-IFRS. For more information on the differences between our consolidated operating expenses pursuant to K-IFRS and pursuant to IFRS Accounting Standards as issued by the IASB, see “— Explanatory Note Regarding Presentation of Certain Financial Information under K-IFRS.” Segment operating expenses presented above, which represent the difference between segment revenue and segment operating profit (loss), are not separately reviewed by or reported to our chief operating decision maker. (9) Segment operating profit (loss) for each of the segments above is presented net of consolidation adjustments. Accordingly, they do not reconcile with the segment operating profit (loss) for each of such segments set forth in note 4(1) of the notes to our consolidated financial statements, which is expressed prior to making such consolidation adjustments. 57 Table of Contents 2025 Compared to 2024 Operating Revenue and Other Income. Our consolidated operating revenue and other income decreased by 4.1% to Won 17,269.6 billion in 2025 from Won 18,012.9 billion, due to a decrease in operating revenue, offset in small part by an increase in other income, as discussed below. Our consolidated operating revenue decreased by 4.7% to Won 17,099.2 billion in 2025 from Won 17,940.6 billion in 2024, due to decreases in cellular services revenue and others revenue, which were partially offset by an increase in fixed-line telecommunications services revenue. Our consolidated other income increased by 135.7% to Won 170.4 billion in 2025 from Won 72.3 billion in 2024, primarily due to the gain on disposal of property and equipment and intangible assets we recognized in 2025 relating to the disposal of our Pangyo office building. The following sets forth additional information about our operating revenues with respect to each of our reportable segments. • Cellular services: The revenue of our cellular services segment, which is composed of revenues from wireless service, cellular interconnection, wireless device sales and miscellaneous cellular services, decreased by 5.7% to Won 12,552.5 billion in 2025 from Won 13,318.2 billion in 2024. The decrease in our cellular services revenue was mainly due to a decrease in wireless service revenue, which was enhanced by decreases in wireless device sales revenue and cellular interconnection revenue. - Wireless service revenue decreased by 6.6% to Won 9,715.6 billion in 2025 from Won 10,401.6 billion in 2024, primarily attributable to discounts on monthly subscription fees we offered for the month of August 2025 as part of the Customer Appreciation Package following the cybersecurity incident of which we became aware in April 2025 as described above. See “— Overview — Cybersecurity.” - Wireless device sales revenue decreased by 4.1% to Won 1,034.7 billion in 2025 from Won 1,078.7 billion in 2024, primarily due to the decrease in the sales volume of the handsets we sold during the year, which was also mainly attributable to the cybersecurity incident described above. See “— Overview — Cybersecurity.” - Cellular interconnection revenue decreased by 7.6% to Won 369.9 billion in 2025 from Won 400.5 billion in 2024, primarily attributable to a decrease in interconnection rates. • Fixed-line telecommunications services: The revenue of our fixed-line telecommunication services segment, which is composed of revenues from broadband Internet service and advanced media platform service (including IPTV and cable TV services), fixed-line telephone service, international calling service, fixed-line interconnection and miscellaneous fixed-line telecommunication services, increased by 2.8% to Won 4,191.1 billion in 2025 from Won 4,075.4 billion in 2024, due to an increase in miscellaneous fixed-line telecommunication services revenue, offset in part by decreases in fixed-line telephone service revenue and international calling service revenue. - Miscellaneous fixed-line telecommunication services revenue increased by 12.4% to Won 1,327.2 billion in 2025 from Won 1,180.9 billion in 2024, primarily due to an increase in revenue from our business communications and related infrastructure services, including our data center services. - Fixed-line telephone service revenue decreased by 8.9% to Won 142.5 billion in 2025 from Won 156.5 billion in 2024, primarily due to a decrease in the number of fixed-line telephone subscribers to 3.3 million as of December 31, 2025 from 3.4 million as of December 31, 2024. - International calling service revenue decreased by 6.0% to Won 200.9 billion in 2025 from Won 213.7 billion in 2024, primarily due to a decrease in international calling volume. 58 Table of Contents • Others: The revenue of our others segment decreased by 35.0% to Won 355.6 billion in 2025 from Won 547.0 billion in 2024, primarily due to an 80.9% decrease in our miscellaneous others revenue to Won 42.7 billion in 2025 from Won 223.4 billion in 2024, which mainly reflected the disposal of our former subsidiary SK M&Service in February 2025, and no recognized revenue from our portal service business in 2025 compared to Won 21.3 billion in 2024, which reflected the disposal of our former subsidiary NATE Communications Corporation in January 2025. See “— Overview — Operational Efficiency.” Such decreases were slightly offset by a 3.5% increase in the revenue of SK Stoa’s T-commerce business to Won 312.9 billion in 2025 from Won 302.3 billion in 2024, which mainly reflected an increase in the gross value of merchandise sold. Operating Expenses. Our consolidated operating expenses decreased by 0.6% to Won 16,221.1 billion in 2025 from Won 16,322.0 billion in 2024, primarily due to a 2.6% decrease in depreciation and amortization expenses to Won 3,467.1 billion in 2025 from Won 3,560.4 billion in 2024, a 1.3% decrease in commission expenses to Won 5,494.7 billion in 2025 from Won 5,564.3 billion in 2024, an 8.3% decrease in network interconnection expenses to Won 635.1 billion in 2025 from Won 692.9 billion in 2024 and a 4.3% decrease in cost of goods sold to Won 1,269.5 billion in 2025 from Won 1,326.2 billion in 2024, partially offset by a 10.5% increase in other operating expenses to Won 2,059.3 billion in 2025 from Won 1,864.0 billion in 2024. The decrease in depreciation and amortization expenses was primarily related to a decrease in acquisitions of property and equipment, a decrease in the amortization expenses for our frequency usage rights, as well as the expiration of the applicable amortization period for certain of our software assets. The decrease in commission expenses was primarily due to the expiration of the amortization period for capitalized commissions from prior years. The decrease in network interconnection expenses was primarily due to decreases in wireless-to-fixed-line and fixed-line-to-wireless interconnection rates. The decrease in cost of goods sold was primarily due to a decrease in the number of wireless devices sold in 2025. The increase in other operating expenses was primarily due to the USIM replacement fees incurred in connection with the cybersecurity incident described above. See “— Overview — Cybersecurity.” The following sets forth additional information about our segment operating expenses with respect to each of our reportable segments, which do not include certain expenses that are classified as other non-operating expenses under K-IFRS. For more information on the difference between our consolidated operating expenses pursuant to K-IFRS and pursuant to IFRS Accounting Standards as issued by the IASB, see “— Explanatory Note Regarding Presentation of Certain Financial Information under K-IFRS” and note 4(2) of the notes to our consolidated financial statements. • Cellular services: The segment operating expenses for our cellular services segment increased by 0.5% to Won 11,808.3 billion in 2025 from Won 11,746.3 billion in 2024, primarily due to the USIM replacement fees incurred in connection with the cybersecurity incident described above. See “— Overview — Cybersecurity.” • Fixed-line telecommunication services: The segment operating expenses for our fixed-line telecommunication services segment increased by 2.1% to Won 3,834.8 billion in 2025 from Won 3,754.7 billion in 2024, primarily due to an increase in SK Broadband’s labor costs, which in turn primarily reflected the one-time costs of engaging in a voluntary retirement program and higher wage levels, as well as an increase in depreciation expense in connection with its acquisition of the business operations of the Pangyo Data Center from SK Inc. 59 Table of Contents • Others: The segment operating expenses for our others segment decreased by 37.9% to Won 382.9 billion in 2025 from Won 616.2 billion in 2024, primarily reflecting the disposals of our former subsidiaries NATE Communications Corporation and SK M&Service in January 2025 and February 2025, respectively. Operating Profit. Our consolidated operating profit significantly decreased by 38.0% to Won 1,048.5 billion in 2025 from Won 1,690.9 billion in 2024, as the decrease in operating revenue and other income outpaced the decrease in operating expenses in 2025. The following sets forth additional information about our segment operating profit (loss) with respect to each of our reportable segments. Our segment operating profit (loss) with respect to each of our reportable segments is based on K-IFRS and the sum of segment operating profit for all three reportable segments differs from our consolidated operating profit presented in accordance with IFRS Accounting Standards as issued by the IASB. For a reconciliation of operating profit presented in accordance with IFRS Accounting Standards as issued by the IASB and operating profit presented in accordance with K-IFRS, see “— Explanatory Note Regarding Presentation of Certain Financial Information under K-IFRS” and note 4(2) of the notes to our consolidated financial statements. • Cellular services: The segment operating profit of our cellular services segment decreased by 52.7% to Won 744.2 billion in 2025 from Won 1,571.9 billion in 2024, due to the greater decrease in segment operating revenue as compared to the decrease in segment operating expenses, for the various reasons described above. The segment operating margin (which, with respect to each reportable segment, is segment operating profit (loss) divided by revenue from such segment, expressed as a percentage) of our cellular services segment decreased to 5.9% in 2025 from 11.8% in 2024. • Fixed-line telecommunication services: The segment operating profit of our fixed-line telecommunication services segment increased by 11.1% to Won 356.3 billion in 2025 from Won 320.7 billion in 2024, due to the greater increase in segment operating revenue as compared to the increase in segment operating expenses, for the reasons described above. The segment operating margin of our fixed-line telecommunication services segment increased to 8.5% in 2025 from 7.9% in 2024. • Others: The segment operating loss of our others segment decreased by 60.5% to Won 27.3 billion in 2025 from Won 69.2 billion in 2024, due to the greater decrease in segment operating expenses as compared to the decrease in segment operating revenue as described above. The segment operating margin of our others segment improved to (7.7)% in 2025 from (12.7)% in 2024. Finance Income and Finance Costs. Our finance income decreased by 38.2% to Won 219.4 billion in 2025 from Won 355.0 billion in 2024, primarily due to a 69.4% decrease in gain relating to financial instruments at fair value through profit or loss to Won 58.3 billion in 2025 from Won 190.4 billion in 2024, primarily reflecting the base effect of gain on derivatives recognized in 2024 in connection with our acquisition of additional equity interest in SK Broadband. Our finance costs decreased by 20.4% to Won 482.0 billion in 2025 from Won 605.9 billion in 2024, primarily due to a significant decrease in loss relating to financial instruments at fair value through profit or loss to Won 16.4 billion in 2025 from Won 133.0 billion in 2024, primarily reflecting the significantly higher loss recognized in 2024 in connection with a forward transaction related to our investment in Penguin Solutions Inc. Gains (Losses) Related to Investments in Subsidiaries, Associates and Joint Ventures. We recorded losses related to investments in subsidiaries, associates and joint ventures of Won 63.6 billion in 2025, primarily due to our share of loss from Rebellions, Inc. (formerly known as SAPEON Korea Inc.) of Won 77.6 billion, compared to gains related to investments in subsidiaries, associates and joint ventures of Won 321.8 billion in 2024, primarily in connection with the one-time effect of reclassification of our equity interest in SAPEON Korea Inc. from a consolidated subsidiary to an associate, following its merger with and into Rebellions, Inc. in 2024. 60 Table of Contents Income Tax. Income tax expense decreased by 7.3% to Won 347.2 billion in 2025 from Won 374.7 billion in 2024 primarily due to a 59.0% decrease in profit before income tax to Won 722.3 billion in 2025 from Won 1,761.8 billion in 2024. Such decrease was partially offset by income tax paid and other of Won 111.8 billion in 2025 compared to income tax refund and other of Won 18.3 billion in 2024. Our effective tax rate in 2025 increased to 48.1% from 21.3% in 2024. Our effective tax rate in 2025 was greater than the maximum statutory tax rate of 26.4%, primarily due to additional income tax resulting from a change in the tax authority’s interpretation. Our effective tax rate in 2024 was lower than the maximum statutory tax rate of 26.4%, primarily due to changes in unrecognized deferred taxes as well as tax credits and tax reductions. Profit for the Year. Principally as a result of the factors discussed above, our profit for the year decreased by 73.0% to Won 375.1 billion in 2025 from Won 1,387.1 billion in 2024. Profit for the year as a percentage of operating revenue and other income was 2.2% in 2025 compared to 7.7% in 2024. 2024 Compared to 2023 Operating Revenue and Other Income. Our consolidated operating revenue and other income increased by 2.0% to Won 18,012.9 billion in 2024 from Won 17,658.9 billion in 2023 due to increases in operating revenue and, to a much lesser extent, other income, as discussed below. Our consolidated operating revenue increased by 1.9% to Won 17,940.6 billion in 2024 from Won 17,608.5 billion in 2023, due to increases in cellular services revenue and fixed-line telecommunications services revenue, which were slightly offset by a decrease in others revenue. Our consolidated other income increased by 43.5% to Won 72.3 billion in 2024 from Won 50.4 billion in 2023, primarily due to the gain on disposal of property and equipment and intangible assets we recognized in 2024 relating to certain ancillary properties. The following sets forth additional information about our operating revenues with respect to each of our reportable segments. • Cellular services: The revenue of our cellular services segment, which is composed of revenues from wireless service, cellular interconnection, wireless device sales and miscellaneous cellular services, increased by 1.5% to Won 13,318.2 billion in 2024 from Won 13,123.2 billion in 2023. The increase in our cellular services revenue was due to increases in wireless device sales revenue, wireless service revenue and miscellaneous cellular services revenue, partially offset by a decrease in cellular interconnection revenue. - Wireless device sales revenue increased by 8.5% to Won 1,078.7 billion in 2024 from Won 993.9 billion in 2023, primarily due to increases in the sales volume and average prices of the handsets we sold during the year, which primarily reflected the launch of new high-end flagship devices by leading manufacturers and higher prices charged by such manufacturers. - Wireless service revenue increased by 0.7% to Won 10,401.6 billion in 2024 from Won 10,329.0 billion in 2023, primarily attributable to the continued increase in the number of subscribers who subscribe to our 5G subscription plans and an increase in the usage of our roaming services in light of a further increase in international travel by our subscribers. - Miscellaneous cellular services revenue increased by 5.1% to Won 1,437.4 billion in 2024 from Won 1,367.6 billion in 2023, primarily due to increases in revenue from our cloud services, IoT solutions and other new businesses, as we continued to build up the scale of such businesses to complement our core wireless service business. - Cellular interconnection revenue decreased by 7.4% to Won 400.5 billion in 2024 from Won 432.7 billion in 2023, primarily attributable to a decrease in interconnection rates. 61 Table of Contents • Fixed-line telecommunications services: The revenue of our fixed-line telecommunication services segment, which is composed of revenues from broadband Internet service and advanced media platform service (including IPTV and cable TV services), fixed-line telephone service, international calling service, fixed-line interconnection and miscellaneous fixed-line telecommunication services, increased by 3.8% to Won 4,075.4 billion in 2024 from Won 3,928.0 billion in 2023, primarily due to increases in miscellaneous fixed-line telecommunication services revenue, and to a lesser extent, international calling service revenue, broadband Internet service and advanced media platform service revenue, and fixed-line telephone service revenue, slightly offset by a decrease in fixed-line interconnection revenue. - Miscellaneous fixed-line telecommunication services revenue increased by 9.4% to Won 1,180.9 billion in 2024 from Won 1,079.6 billion in 2023, primarily due to an increase in revenue from our business communications and related infrastructure services, including our data center services. - International calling service revenue increased by 11.9% to Won 213.7 billion in 2024 from Won 190.9 billion in 2023, primarily due to an increase in international calling volume. - Revenue from our broadband Internet service and advanced media platform service (including our IPTV and cable TV services) slightly increased by 0.7% to Won 2,510.3 billion in 2024 from Won 2,494.0 billion in 2023, primarily due to an increase in the number of IPTV subscribers to 6.8 million subscribers as of December 31, 2024 from 6.7 million subscribers as of December 31, 2023. - Fixed-line telephone service revenue increased by 6.0% to Won 156.5 billion in 2024 from Won 147.7 billion in 2023, primarily due to an increase in calling volume, including those relating to the National Assembly election campaigns in 2024. - Fixed-line interconnection revenue decreased by 11.4% to Won 14.0 billion in 2024 from Won 15.8 billion in 2023, primarily due to a continued decrease in interconnection rates, as well as decreases in residential calling volume and the number of fixed-line telephone subscribers to 3.4 million as of December 31, 2024 from 3.5 million as of December 31, 2023. • Others: The revenue of our others segment slightly decreased by 1.8% to Won 547.0 billion in 2024 from Won 557.3 billion in 2023, primarily due to a 4.1% decrease in our miscellaneous others revenue, which mainly reflected a decrease in revenue we derived from our former subsidiary SK M&Service, and an 8.2% decrease in our portal service revenue derived from our former subsidiary NATE Communications Corporation. Such decreases were partially offset by a 0.3% increase in the revenue of SK Stoa’s T-commerce business to Won 302.3 billion in 2024 from Won 301.3 billion in 2023, which mainly reflected an increase in the gross value of merchandise sold. Operating Expenses. Our consolidated operating expenses increased by 2.6% to Won 16,322.0 billion in 2024 from Won 15,902.6 billion in 2023, primarily due to a 9.5% increase in labor costs to Won 2,725.8 billion in 2024 from Won 2,488.2 billion in 2023, a 12.9% increase in other operating expenses to Won 1,864.0 billion in 2024 from Won 1,651.3 billion in 2023 and a 4.7% increase in cost of goods sold to Won 1,326.2 billion in 2024 from Won 1,266.4 billion in 2023, partially offset by a 1.5% decrease in depreciation and amortization expenses to Won 3,560.4 billion in 2024 from Won 3,614.8 billion in 2023 and a 21.0% decrease in advertising expenses to Won 186.3 billion in 2024 from Won 235.8 billion in 2023. The increase in labor costs was primarily due to our one-time implementation of a voluntary retirement program and a general increase in the base salary of our employees. The increase in other operating expenses was primarily due to an increase in impairment loss on property and equipment and intangible assets related to the replacement of outdated equipment and our recognition of the expected amount of certain administrative fine of Won 42.6 billion, which was provisionally announced by the 62 Table of Contents KFTC in March 2025 (see “Item 8.A. — Consolidated Statements and Other Financial Information — Legal Proceedings — KFTC Proceedings”), as well as an increase in utilities, mainly reflecting an increase in electricity prices. The increase in cost of goods sold was primarily due to increases in sales of merchandise under our T Universe subscription program and solutions businesses to our enterprise customers. The decrease in depreciation and amortization expenses was primarily related to the expiration of the applicable amortization period for certain of our software assets and a decrease in the amortization expenses for our frequency usage rights, as well as a decrease in acquisitions of property and equipment. The decrease in advertising expenses was primarily due to continued stabilization of the market for wireless service subscribers and our efficient management of marketing fees as part of our ongoing organizational efforts to enhance operational efficiency, as well as the base effect of our extensive advertising campaigns in 2023 as part of our efforts to promote the City of Busan’s bid to host the World Expo 2030. The following sets forth additional information about our segment operating expenses with respect to each of our reportable segments, which do not include certain expenses that are classified as other non-operating expenses under K-IFRS. For more information on the difference between our consolidated operating expenses pursuant to K-IFRS and pursuant to IFRS Accounting Standards as issued by the IASB, see “— Explanatory Note Regarding Presentation of Certain Financial Information under K-IFRS” and note 4(2) of the notes to our consolidated financial statements. • Cellular services: The segment operating expenses for our cellular services segment slightly increased by 0.6% to Won 11,746.3 billion in 2024 from Won 11,673.1 billion in 2023, due to the increase in SK Telecom’s labor costs as described above, which was substantially offset by a decrease in commissions paid to SK Telecom’s authorized dealers and independent retailers, as the market for new 5G subscribers continued to stabilize, and a decrease in depreciation and amortization expenses, primarily reflecting the expiration of the applicable amortization period for certain of our software assets and a decrease in the amortization expenses for our frequency usage rights, as well as a decrease in acquisitions of property and equipment. • Fixed-line telecommunication services: The segment operating expenses for our fixed-line telecommunication services segment increased by 4.8% to Won 3,754.7 billion in 2024 from Won 3,582.1 billion in 2023, primarily due to increases in SK Broadband’s labor costs, primarily reflecting higher wage levels and associated retirement benefits, as well as in marketing expenses and commissions, primarily reflecting increases in the sale of broadband Internet and IPTV service subscriptions. • Others: The segment operating expenses for our others segment increased by 2.7% to Won 616.2 billion in 2024 from Won 600.1 billion in 2023, primarily due to increases in utilities and costs of goods sold as well as labor costs. Operating Profit. Our consolidated operating profit decreased by 3.7% to Won 1,690.9 billion in 2024 from Won 1,756.3 billion in 2023, as the increase in operating expenses outpaced the increase in operating revenue and other income in 2024. The following sets forth additional information about our segment operating profit (loss) with respect to each of our reportable segments. Our segment operating profit (loss) with respect to each of our reportable segments is based on K-IFRS and the sum of segment operating profit for all three reportable segments differs from our consolidated operating profit presented in accordance with IFRS Accounting Standards as issued by the IASB. For a reconciliation of operating profit presented in accordance with IFRS Accounting Standards as issued by the IASB and operating profit presented in accordance with K-IFRS, see “— Explanatory Note Regarding 63 Table of Contents Presentation of Certain Financial Information under K-IFRS” and note 4(2) of the notes to our consolidated financial statements. • Cellular services: The segment operating profit of our cellular services segment increased by 8.4% to Won 1,571.9 billion in 2024 from Won 1,450.1 billion in 2023, due to the greater increase in segment operating revenue as compared to the increase in segment operating expenses, for the various reasons described above. The segment operating margin (which, with respect to each reportable segment, is segment operating profit (loss) divided by revenue from such segment, expressed as a percentage) of our cellular services segment increased to 11.8% in 2024 from 11.0% in 2023. • Fixed-line telecommunication services: The segment operating profit of our fixed-line telecommunication services segment decreased by 7.3% to Won 320.7 billion in 2024 from Won 345.9 billion in 2023, due to the greater increase in segment operating expenses as compared to the increase in segment operating revenue, for the reasons described above. The segment operating margin of our fixed-line telecommunication services segment decreased to 7.9% in 2024 from 8.8% in 2023. • Others: The segment operating loss of our others segment increased by 61.7% to Won 69.2 billion in 2024 from Won 42.8 billion in 2023, due to the increase in segment operating expenses as compared to the decrease in segment operating revenue as described above. As a result, the segment operating margin of our others segment worsened to (12.7)% in 2024 from (7.7)% in 2023. Finance Income and Finance Costs. Our finance income increased by 42.9% to Won 355.0 billion in 2024 from Won 248.4 billion in 2023, primarily due to a 65.6% increase in gain relating to financial instruments at fair value through profit or loss to Won 190.4 billion in 2024 from Won 115.0 billion in 2023, primarily relating to gain on derivatives recognized in connection with our acquisition of additional equity interest in SK Broadband. The effect of such increase was enhanced by a 24.4% increase in interest income to Won 87.2 billion in 2024 from 70.1 billion in 2023, which mainly reflected an increase in the average volume of our interest-earning financial assets. Our finance costs increased by 14.9% to Won 605.9 billion in 2024 from Won 527.4 billion in 2023, primarily due to a significant increase in loss relating to financial instruments at fair value through profit or loss to Won 133.0 billion in 2024 from Won 49.6 billion in 2023, primarily relating to forward transaction loss from our investment in Penguin Solutions Inc. The effect of such increase was enhanced by a 3.4% increase in interest expense to Won 403.1 billion in 2024 from Won 389.8 billion in 2023, which mainly reflected our refinancing of maturing debt at higher interest rates in recent years, as the market interest rates were generally higher in more recent periods compared to earlier periods over the past few years. The impact of such increases was partially offset by a decrease in loss on sale of accounts receivable – other related to our sale of accounts receivable for handset installment payments to Won 35.3 billion in 2024 from Won 65.0 billion in 2023. Gains Related to Investments in Subsidiaries, Associates and Joint Ventures. Gains related to investments in subsidiaries, associates and joint ventures significantly increased to Won 321.8 billion in 2024 from Won 10.9 billion in 2023, primarily due to the reclassification of our equity interest in SAPEON Korea Inc. from a consolidated subsidiary to an associate, following its merger with and into Rebellions, Inc. during 2024. Income Tax. Income tax expense increased by 9.5% to Won 374.7 billion in 2024 from Won 342.2 billion in 2023 primarily due to an 18.4% increase in profit before income tax to Won 1,761.8 billion in 2024 from Won 1,488.2 billion in 2023. Our effective tax rate in 2024 decreased to 21.3% from 23.0% in 2023. Our effective tax rates in 2024 and 2023 were lower than the maximum statutory tax rate of 26.4% for both years, primarily due to, in the case of 2024, changes in unrecognized deferred taxes as well as tax credits and tax reductions, and in the case of 2023, tax credits and tax reductions. Profit for the Year. Principally as a result of the factors discussed above, our profit for the year increased by 21.0% to Won 1,387.1 billion in 2024 from Won 1,145.9 billion in 2023. Profit for the year as a percentage of operating revenue and other income was 7.7% in 2024 compared to 6.5% in 2023. 64 Table of Contents Item 5.B. Liquidity and Capital Resources Liquidity We had a working capital surplus (current assets in excess of current liabilities) of Won 197.4 billion as of December 31, 2025, a working capital deficit (current liabilities in excess of current assets) of Won 1,747.6 billion as of December 31, 2024 and a working capital deficit of Won 408.4 billion as of December 31, 2023. The increase in our working capital as of December 31, 2025 compared to December 31, 2024 was mainly due to a decrease in our current liabilities, primarily in relation to current portion of long-term debt, net and accounts payable – other, which outpaced the decrease in our current assets, primarily in relation to cash and cash equivalents. We plan to fund our current liabilities with the cash flow generated by our operations, proceeds from the disposal of investment securities or property and equipment that are no longer deemed profitable and proceeds from additional borrowings, as necessary. We had cash and cash equivalents, short-term financial instruments and short-term investment securities of Won 1,676.7 billion as of December 31, 2025, Won 2,347.6 billion as of December 31, 2024 and Won 1,749.9 billion as of December 31, 2023. We had outstanding short term borrowings and current portion of long-term debt of Won 1,252.6 billion as of December 31, 2025, Won 2,560.1 billion as of December 31, 2024 and Won 1,621.8 billion as of December 31, 2023. As of December 31, 2025, SK Telecom had credit lines with several local banks that provided for borrowing of up to Won 1,050 billion, all of which was available for borrowing. Cash flows from operating activities and debt financing have been our principal sources of liquidity. We had cash and cash equivalents of Won 1,490.0 billion as of December 31, 2025, Won 2,023.7 billion as of December 31, 2024 and Won 1,455.0 billion as of December 31, 2023. We believe that we have a variety of alternatives available to us to satisfy our financial requirements to the extent that they are not met by funds generated by operations, including the issuance of debt securities and bank borrowings. Year ended December 31, Change 2025 2024 2023 2024 to 2025 2023 to 2024 (In billions of Won, except percentages) Net cash provided by operating activities W 3,923.8 W 5,087.3 W 4,947.2 W (1,163.5 ) (22.9 )% W 140.1 2.8 % Net cash used in investing activities (1,737.1 ) (2,711.8 ) (3,352.9 ) 974.7 (35.9 ) 641.1 (19.1 ) Net cash used in financing activities (2,711.8 ) (1,809.9 ) (2,021.0 ) (901.9 ) 49.8 211.1 (10.4 ) Net increase (decrease) in cash and cash equivalents (525.0 ) 565.6 (426.7 ) (1,090.6 ) N.A. 992.3 N.A. Effect of exchange rate changes on cash and cash equivalents (4.1 ) 26.1 (0.6 ) (30.2 ) N.A. 26.7 N.A. Cash and cash equivalents included in assets held for sale (4.6 ) (23.0 ) — 18.4 (80.0 ) (23.0 ) N.A. Cash and cash equivalents at beginning of period 2,023.7 1,455.0 1,882.3 568.7 39.1 (427.3 ) (22.7 ) Cash and cash equivalents at end of period 1,490.0 2,023.7 1,455.0 (533.7 ) (26.4 ) 568.7 39.1 N.A. = Not available Cash Flows from Operating Activities. Net cash provided by operating activities was Won 3,923.8 billion in 2025, Won 5,087.3 billion in 2024 and Won 4,947.2 billion in 2023. Profit for the year was Won 375.1 billion in 65 Table of Contents 2025, Won 1,387.1 billion in 2024 and Won 1,145.9 billion in 2023. Net cash provided by operating activities in 2025 decreased by 22.9% from 2024, primarily due to the decrease in profit for the year as well as an increase in prepaid expenses (mainly reflecting an increase in contract acquisition costs capitalized as prepaid expenses) and a decrease in accrued expenses (mainly reflecting a decrease in employee incentives). Net cash provided by operating activities in 2024 increased by 2.8% from 2023, primarily due to the increase in profit for the year as well as increases in accrued expenses (mainly reflecting an increase in the outstanding year-end payables relating to our operating expenditures and our recognition of the expected amount of certain administrative fine announced by the KFTC in March 2025 as described above) and in withholdings (mainly reflecting an increase in our salary expenses) compared to decreases of such line items in 2023. Cash Flows from Investing Activities. Net cash used in investing activities was Won 1,737.1 billion in 2025, Won 2,711.8 billion in 2024 and Won 3,352.9 billion in 2023. Cash inflows from investing activities were Won 1,384.3 billion in 2025, Won 362.3 billion in 2024 and Won 272.6 billion in 2023. Cash inflows in 2025 mainly reflected proceeds from disposals of long-term investment securities, primarily related to our disposals of shares of Kakao Corp. and Joby Aviation Inc., and proceeds from disposals of property and equipment, mainly related to the sale of an office building in Pangyo. Cash inflows in 2024 mainly reflected collection of short-term loans, primarily related to SK Telecom’s collection of short-term loans that were made to authorized dealers, and proceeds from disposals of investments in associates and joint ventures, mainly related to the reductions of paid-in capital by SK Technology Innovation Company and SK Latin America Investment S.A. Cash outflows for investing activities were Won 3,121.4 billion in 2025, Won 3,074.1 billion in 2024 and Won 3,625.5 billion in 2023. Cash outflows in 2025, 2024 and 2023 were primarily attributable to expenditures related to the acquisition of property and equipment of Won 2,206.6 billion, Won 2,487.4 billion and Won 2,973.9 billion, respectively, primarily in connection with the acquisition of 5G and LTE equipment, the maintenance and enhancement of our 5G network and the maintenance of our LTE network. Cash Flows from Financing Activities. Net cash used in financing activities was Won 2,711.8 billion in 2025, Won 1,809.9 billion in 2024 and Won 2,021.0 billion in 2023. Cash inflows from financing activities were Won 2,258.3 billion in 2025, Won 1,552.2 billion in 2024 and Won 2,416.8 billion in 2023. Such inflows were primarily driven by the issuance of debentures, which provided cash of Won 1,875.3 billion in 2025, Won 1,236.5 billion in 2024 and Won 1,785.1 billion in 2023, as well as proceeds from long-term borrowings, which provided cash of Won 300.0 billion in 2025, Won 200.0 billion in 2024 and Won 50.0 billion in 2023, and proceeds from issuance of hybrid bonds in the case of 2023, which provided cash of Won 398.5 billion. Cash outflows for financing activities were Won 4,970.0 billion in 2025, Won 3,362.0 billion in 2024 and Won 4,437.8 billion in 2023. Cash outflows for financing activities included repayments of debentures, repayments of long-term borrowings, payments of dividends, repayments of long-term payables – other, repayments of lease liabilities and transactions with non-controlling shareholders, among other items. Repayments of debentures were Won 2,121.5 billion in 2025, Won 1,235.8 billion in 2024 and Won 1,869.2 billion in 2023. Repayments of long-term borrowings were Won 312.5 billion in 2025, Won 402.5 billion in 2024 and Won 125.0 billion in 2023. Payments of dividends were Won 628.4 billion in 2025, Won 804.3 billion in 2024 and Won 773.8 billion in 2023. Repayments of long-term payables – other were Won 369.2 billion in 2025, Won 369.2 billion in 2024 and Won 400.2 billion in 2023. Repayments of lease liabilities were Won 372.8 billion in 2025, Won 381.3 billion in 2024 and Won 402.5 billion in 2023. In addition, cash outflow from transactions with non-controlling shareholders was Won 1,145.9 billion in 2025, which mainly related to our acquisition of additional equity interest in SK Broadband from minority shareholders in May 2025. As of December 31, 2025, we had total long-term debt (excluding current portion) outstanding of Won 7,594.4 billion, which included debentures in the amount of Won 7,294.4 billion and bank and institutional borrowings in the amount of Won 300.0 billion. As of December 31, 2024, we had total long-term debt (excluding current portion) outstanding of Won 6,566.7 billion, which included debentures in the amount of Won 6,363.6 billion and bank and institutional borrowings in the amount of Won 203.1 billion. For a description of our long-term debt, see note 17 of the notes to our consolidated financial statements. 66 Table of Contents As of December 31, 2025, we had (i) Won 6,802.0 billion aggregate principal amount of Korean Won-denominated debentures outstanding and (ii) Won 1,434.9 billion aggregate principal amount of debentures outstanding denominated in Dollars. The fixed interest rates of our debentures range from 1.39% to 6.63% depending on the offering size, maturity, interest rate environment at the time of the offering and currency, among other factors. We have a diversified maturity profile with respect to our debentures. See “— Contractual Obligations and Commitments” for more details. As of December 31, 2025, substantially all of our foreign currency-denominated short term and long-term borrowings and debentures, which in the aggregate amounted to 16.2% of our total outstanding short-term and long-term debt, including the current portion and net of present value discount and discounts on bonds as of such date, was denominated in Dollars. However, substantially all of our revenue and operating expenses are denominated in Won. We generally pay for imported capital equipment in Dollars. Appreciation of the Won against the Dollar will result in net foreign currency transaction and translation gains, while depreciation of the Won against the Dollar will result in net foreign currency transaction and translation losses. Changes in foreign currency exchange rates will also affect our liquidity because of the effect of such changes on the amount of funds required for us to make interest and principal payments on our foreign currency-denominated debt. For a description of swap or derivative transactions we have entered into, among other transactions, to mitigate the effects of such losses, see “Item 11. Quantitative and Qualitative Disclosures about Market Risk.” Capital Requirements Historically, capital expenditures, repayment of outstanding debt, frequency usage payments and lease payments have represented our most significant use of funds. In recent years, we have also increasingly dedicated capital resources to develop and invest in innovative new solutions and services, including those utilizing our AI and digital infrastructure capabilities and our telecommunications platforms, as well as to make strategic investments in companies with innovative technology or other complementary offerings of solutions and services. To fund our scheduled debt repayment and planned capital expenditures over the next several years, we intend to rely primarily on cash flows from operating activities, as well as bank and institutional borrowings, and offerings of debt or equity in the domestic or international markets. We believe that these sources will be sufficient to fund our planned capital expenditures for 2026. Our ability to rely on these alternatives could be affected by the liquidity of the Korean financial markets or by Government policies regarding Won and foreign currency borrowings and the issuance of equity and debt. Our failure to make needed expenditures would adversely affect our ability to sustain subscriber growth and provide quality services and, consequently, our results of operations. Capital Expenditures. The following table sets forth our actual capital expenditures for 2025, 2024 and 2023: Year ended December 31, 2025 2024 2023 (In billions of Won) Wireless Networks(1) W 733.9 W 1,259.0 W 1,380.6 Fixed-line Network(2) 885.4 850.2 999.5 Others(3) 587.3 378.2 593.8 Total W 2,206.6 W 2,487.4 W 2,973.9 (1) Includes investments in wireless networks, primarily our 5G, LTE and Wi-Fi networks, as well as other capital expenditures related to our networks. (2) Includes all capital expenditures made by SK Broadband. (3) Includes non-network related investments such as capital expenditures for product development, upgrades of our information technology systems and equipment and investments in data infrastructure. 67 Table of Contents We set our capital expenditure budget for each upcoming year on an annual basis. Our actual capital expenditures in 2025, 2024 and 2023 were Won 2,206.6 billion, Won 2,487.4 billion and Won 2,973.9 billion, respectively. Of such amounts, we spent approximately 33.3%, 50.6% and 46.4%, respectively, on capital expenditures related to building and enhancing our wireless networks. Our capital expenditures related to building and enhancing our wireless networks, including in connection with our 5G network which we launched in 2019, have generally decreased in recent years. See “Item 4.B. Business Overview — Cellular Services — Digital Wireless Network — 5G Network.” Our other non-network related capital expenditures in 2025, 2024 and 2023 primarily related to developing new products, services and technology, upgrades to our information technology systems and equipment and investments in data infrastructure. In particular, we have been making capital expenditures to expand, and subsequently maintain and enhance, our 5G network. We commenced commercial 5G services in April 2019. We have also been making capital expenditures to enhance and maintain our LTE network. For a more detailed description of our 5G and LTE networks, see “Item 4.B. Business Overview — Cellular Services — Digital Wireless Network.” In addition, we have been making capital expenditures to maintain and enhance our fixed-line (including broadband Internet) networks. We plan to continue to make capital investments in 2026 to maintain and enhance our 5G, LTE and fixed-line networks and develop related technologies, as well as to maintain our LTE network. The following table sets forth our payment obligations relating to our acquisitions of frequency usage rights. Spectrum Technology (width) Date of Acquisition (including renewals) Initial Payment Amount (in billions of Won) Initial Payment Year Annual Payment Amount (in billions of Won) Annual Payment Term 800 MHz LTE (20 MHz) Jul. 2021 W 56.8 2021 W 34.1 2022-2026 1.8 GHz LTE (20 MHz + 15 MHz) Dec. 2021 136.9 2021 82.2 2022-2026 2.1 GHz LTE (30 MHz) Dec. 2021 102.9 2021 61.8 2022-2026 WCDMA (10 MHz) 2.6 GHz LTE (40 MHz + 20 MHz) Aug. 2016 332.5 2016 99.8 2017-2026 3.5 GHz 5G (100 MHz) Dec. 2018 304.6 2018 91.4 2019-2028 We currently expect to spend a slightly higher amount for capital expenditures in 2026 compared to 2025 for a range of projects, including investments to maintain and enhance our telecommunications networks (including our 5G and LTE networks), investments to improve and maintain our Wi-Fi network, investments in data infrastructure and computing capabilities, and investments in the development of AI, IoT and other digital solutions and services. In December 2025, the MSIT announced plans to reallocate a total of 370 MHz of frequency bandwidths whose usage terms are due to expire in 2026 to KT, LG U+ and us, 155 MHz (in the 800 MHz, 1.8 GHz, 2.1 GHz and 2.6 GHz spectrums) of which will be allocated to us. We have applied for the renewal of the 20 MHz frequency bandwidth in the 800 MHz spectrum in December 2025, and we plan to apply for the renewal of the remaining 135 MHz of frequency bandwidths in June 2026. The final consideration to be paid by us for such reallocated bandwidths is expected to be conditional on the number of indoor 5G cell sites to be constructed by us by 2031. However, our overall capital expenditure levels and the allocation of such expenditures remain subject to many uncertainties. We may increase, reduce or suspend our planned capital expenditures for 2026 or change the timing and area of our capital expenditure spending from the estimates described above in response to market conditions or for other reasons. We may also make additional capital expenditures and other investments beyond our currently anticipated level as opportunities arise, including in relation to any acquisitions of additional frequency usage rights or execution of additional AI-related investments. Accordingly, we periodically review the amount of our capital expenditures and other investments and may make adjustments based on the current progress of capital expenditure projects and market conditions. No assurance can be given that we will be able to meet any such increased expenditure requirements or obtain adequate financing for such requirements, on terms acceptable to us, or at all. 68 Table of Contents Repayment of Outstanding Debt. As of December 31, 2025, our principal repayment obligations with respect to long-term borrowings, bonds and short-term borrowings outstanding were as follows for the periods indicated: Year Ending December 31, Total (In billions of Won) 2026 W 1,255.1 2027 1,949.0 2028 2,020.9 2029 and thereafter 3,645.0 Lease Payments. Pursuant to IFRS 16, Leases, we recognize right-of-use assets representing our rights to use the underlying assets and lease liabilities representing our obligation to make lease payments in relation to substantially all of our lease arrangements, except for certain short-term leases and leases of low-value assets. As of December 31, 2025, our aggregate current and long-term lease liabilities amounted to Won 1,525.8 billion, which primarily related to land, buildings and structures we leased from third parties in the ordinary course of our business. As of December 31, 2025, our payment obligations with respect to our lease liabilities were as follows for the periods indicated: Year Ending December 31, Total (In billions of Won) 2026 W 420.1 2027 412.5 2028 265.5 2029 and thereafter 678.2 Investments in New Growth Businesses. We may also require capital for investments to support our development of new growth businesses, including, for example, investments in leading AI technology companies to facilitate mutual collaboration. Our notable strategic investments in other companies for such purpose in recent years include the following: • In June 2023, we made an equity investment of US$100 million in Joby Aviation Inc., a transportation company based in Santa Cruz, California, which is developing electric vertical take-off and landing aircrafts, as part of our ongoing efforts to develop emissions-free aerial ridesharing services to cities and communities across Korea. • In August 2023, we made an equity investment of US$100 million in Anthropic PBC, a generative AI technology company based in San Francisco, California, in order to jointly develop a multilanguage large-language model customized for telecommunications companies. • In February 2024, we made an equity investment of US$20 million in Lambda, Inc., a GPU cloud service provider based in San Francisco, California, in order to cooperate on the development and launch of GPUaaS and AI data center solutions and services. • In June 2024, we made an equity investment of US$10 million in Perplexity AI, Inc., an AI technology company based in San Francisco, California, in order to cooperate on the development of generative AI search engine services. • In December 2024, we made an equity investment of US$200 million in Penguin Solutions Inc., a leading designer and developer of enterprise solutions based in Milpitas, California, in order to cooperate on the development of differentiated global end-to-end AI factory and data center solutions and services. To date, we have made more than US$300 million on a cumulative basis in AI-related investments, and we seek to continue making such and other investments in furtherance of our growth strategy. See “Item 4.B. Business Overview — Our Business Strategy.” 69 Table of Contents From time to time, we may make other investments in telecommunications or other businesses in Korea or abroad, where we perceive attractive opportunities for investment. From time to time, we may also dispose of existing investments when we believe that doing so would be in our best interest. See “— Overview — Operational Efficiency.” Severance Payments. The present value of our defined benefit obligations, which is the present value of total accrued and unpaid retirement and severance benefits for our employees, as of December 31, 2025, was Won 1,051.5 billion, which was more than offset by the fair value of our defined benefit plan assets of Won 1,257.0 billion as of such date. Accordingly, we recognized defined benefit assets of Won 205.5 billion as of December 31, 2025. Also see “Item 6.D. Employees — Employee Benefits” and note 20 of the notes to our consolidated financial statements. Dividends. Total cash outflows for payments of dividends amounted to Won 628.4 billion in 2025, Won 804.3 billion in 2024 and Won 773.8 billion in 2023. Contractual Obligations and Commitments The following summarizes our contractual cash obligations (excluding short-term leases and leases of low-value assets) at December 31, 2025, and the effect such obligations are expected to have on liquidity and cash flow in future periods: Payments Due by Period(1) Total Less Than 1 Year 1-3 Years 4-5 Years More Than 5 Years (In billions of Won) Bonds Principal W 8,236.9 W 922.0 W 3,669.9 W 1,795.0 W 1,850.0 Interest 1,089.6 277.3 388.7 168.6 255.1 Long-term borrowings Principal 503.1 203.1 300.0 — — Interest 20.5 14.4 6.1 — — Lease liabilities 1,776.3 420.1 678.0 359.1 319.1 Facility deposits 10.7 5.0 — — 5.7 Other long-term payables(2) Principal 551.9 369.2 182.8 — — Interest 13.9 9.3 4.6 — — Short-term borrowings 130.0 130.0 — — — Total contractual cash obligations W 12,332.9 W 2,350.2 W 5,230.2 W 2,322.6 W 2,429.9 (1) We are contractually obligated to make severance payments to eligible employees we have employed for more than one year, upon termination of their employment, regardless of whether such termination is voluntary or involuntary. Accruals for severance indemnities are recorded based on the amount we would be required to pay in the event the employment of all our employees were to terminate at the balance date. However, we have not yet estimated cash flows for future periods. Accordingly, payments due in connection with severance indemnities have been excluded from this table. (2) Related to acquisition of frequency licenses. See note 18 of the notes to our consolidated financial statements. See note 36 of the notes to our consolidated financial statements for details related to our other commitments and contingencies. 70 Table of Contents Item 5.C. Research and Development, Patents and Licenses, etc. We maintain a high level of spending on our research and development activity. We also donate funds to several Korean research institutes and educational organizations that focus on research and development activity. We believe that we must maintain a substantial in-house technology capability to achieve our strategic goals. The main focus of our research and development activity is the development of new wireless technologies and services and value-added technologies and services for our 5G network and LTE network, such as wireless data communications, as well as the development of new technologies that reflect the growing convergence between telecommunications and other industries, such as AI, big data analytics and media. SK Telecom’s research and development activity is primarily conducted through our SK AI Research and Development Center, which is subdivided into the Future Research and Development Laboratory, AI DC Laboratory, Open AIX Laboratory, Vision Laboratory, Media Laboratory, Digital Twin Laboratory and the AI Model Laboratory. The Infrastructure Technology Division of the Network Infrastructure Center also conducts related research and development activities. Each business unit also has its own research team that can concentrate on specific short-term research needs, and some of our consolidated subsidiaries also have their own research and development organizations to focus on activities related to their respective business areas. Such research teams permit our research center to concentrate on long-term, technology-intensive research projects. We aim to establish strategic alliances with selected domestic and foreign companies with a view to exchanging or jointly developing technologies, products and services. See “Item 5.A. Operating Results — Overview — Operational Efficiency.” Item 5.D. Trend Information These matters are discussed under “Item 5.A. Operating Results” and “Item 5.B. Liquidity and Capital Resources” above where relevant. Item 5.E. Critical Accounting Estimates Our financial statements are prepared in accordance with IFRS Accounting Standards as issued by the IASB. See notes 2(4) and 3 of the notes to our consolidated financial statements which provide summaries of certain critical accounting estimates that require our management to make difficult, complex or subjective judgments relating to matters which are highly uncertain and that may have a material impact on our financial conditions and results of operations. Item 6. DIRECTORS, SENIOR MANAGEMENT AND EMPLOYEES