All references to “MHz” contained in this annual report shall mean megahertz, a unit of frequency denoting one million cycles per second. All references to “GHz” shall mean gigahertz, a unit of frequency denoting one billion cycles per second. All references to “Mbps” shall mean one million bits per second and all references to “Gbps” shall mean one billion bits per second. All references to “GB” shall mean gigabytes, which is one billion bytes. Any discrepancies in any table between totals and the sums of the amounts listed are due to rounding.

All references to “Won,” or “￦” in this annual report are to the currency of Korea and all references to “Dollars,” “U.S. dollar” or “US$” are to the currency of the United States of America.

The Ministry of Science and ICT (the “MSIT”) is charged with regulating information and telecommunications, and the Korea Communications Commission (the “KCC”) is charged with regulating the public interest aspects of and fairness in broadcasting. Subscriber information for the wireless and fixed-line telecommunications industry set forth in this annual report are derived from information published by the MSIT unless expressly stated otherwise.

The consolidated financial statements included in this annual report are prepared in accordance with International Financial Reporting Standards (“IFRS”), as issued by the International Accounting Standards Board (the “IASB”). As such, we make an explicit and unreserved statement of compliance with IFRS, as issued by the IASB, with respect to our consolidated financial statements as of December 31, 20212022 and 2020,2021, and for the years ended December 31, 2022, 2021 2020 and 20192020, included in this annual report.

Unless expressly stated otherwise, all financial data included in this annual report are presented on a consolidated basis.

Forward-looking statements in this annual report include, but are not limited to, statements about the following:

Not applicable.

Not applicable.

Not applicable.

Not applicable.

Not applicable.

Not applicable.

We face substantial competition across all of our businesses, including our wireless telecommunications business. We expect competition to intensify as a result of the development of new technologies, products and services. We expect that such trends will continue to put downward pressure on the rates we can charge our subscribers.

Historically, there has been considerable consolidation in the telecommunications industry, resulting in the current competitive landscape comprising three mobile and fixed network operators in the Korean market, us, KT Corporation (“KT”) and LG Uplus Corp. (“LG U+”). Each of our competitors has substantial financial, technical, marketing and other resources to respond to our business offerings. As of December 31, 2021,2022, the collective market share of KT and LG U+ amounted to approximately 55.7%56.8% in terms of number of wireless subscribers (including an aggregate of 11.4%13.8% attributable to mobile virtual network operators (“MVNOs”) that lease KT’s and LG U+’s respective networks).

Our competitors for subscriber activations include MVNOs, including MVNOs that lease our networks. MVNOs generally provide rate plans that are relatively cheaper than similar rate plans of the wireless network providers from which they lease their networks, including us. In recent years, a number of new entrants have entered the MVNO business, including affiliates of leading financial institutions in Korea. Some of these new entrants have engaged in aggressive marketing campaigns and promotional discounts while leveraging the brand

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We believe that an increase in market share of MVNOs (including through the entrance of new MVNOs, if any) and the entrance of new mobile network operators (including in connection with the potential allocation of 800 MHz of bandwidth in the 28 GHz spectrum to a new mobile network operator, as announced by the MSIT in January 2023), if any, in the wireless telecommunications market may further increase competition in the telecommunications sector, as well as cause downward price pressure on the fees we charge for our services, which, in turn, may have a material adverse effect on our business, financial position and results of operations.

Our fixed-line telephone service competes with KT and LG U+, as well as other providers of voice over Internet protocol (“VoIP”) services. As of December 31, 2021,2022, our market share of the fixed-line telephone and VoIP service market was 15.7%15.6% (including the services provided by SK Broadband Co., Ltd. (“SK Broadband”)) in terms of number of subscribers compared to KT with 56.3%55.0% and LG U+ with 19.0%18.7%. In addition, our broadband Internet access, Internet protocol TV (“IPTV”) and cable TV services provided through SK Broadband compete with other providers of such services, including KT, LG U+ and cable companies. Furthermore, our IPTV and cable TV services are facing an increasing level of competition from global operators of online video streaming platforms, such as YouTube, Netflix, Disney Plus and Amazon Video,Apple TV, leading domestic video streaming platforms such as TVING, WatchaaWavve, Coupang Play and Wavve,Watchaa, and the video services offered by leading domestic online and mobile search and communications platforms including NAVER and Kakao, as such services continue to become increasingly popular to serve as a substitute to traditional television programming. As of December 31, 2021,2022, our market share of the broadband Internet market was 28.7%28.5% in terms of number of subscribers compared to KT with 41.2%41.3% and LG U+ with 20.7%21.0%. As of December 31, 2021,2022, our market share of the pay TV market (which includes IPTV, cable TV and satellite TV) was 25.0%25.6% compared to KT with 36.2%36.6% (including its IPTV, cable TV and satellite TV services) and LG U+ with 25.3%24.8% (including its IPTV and cable TV services), and the collective market share of other pay TV providers was 13.4%13.1%.

Our ability to compete successfully in all of the businesses in which we operate will depend on our ability to anticipate and respond to various competitive factors affecting the respective industries, including new services that may be introduced, changes in consumer preferences, economic conditions and discount pricing strategies by competitors.

In addition to introducing new technologies and offerings, we must phase out outdated and unprofitable technologies and services. For example, as of January 2019, we discontinued our wireless broadband Internet access (“WiBro”) services in January 2019 and we also terminated our second generation CDMA wireless services in July 2020. If we are unable to do sointroduce new technologies and offerings on a cost-effective and timely basis, our business, financial condition and results of operations could be adversely affected.

Our businesses are generally subject to governmental supervision and various types of regulation.

We also qualify as a “market-dominating business entity” under the Fair Trade Act, which subjects us to additional regulations and we are prohibited from engaging in any act of abusing our position as a market-dominating entity. See “Item 4.B. Business Overview — Law and Regulation — Competition Regulation.” The additional regulations to which we are subject hashave affected our competitiveness in the past and may materially hurt our profitability and impede our ability to compete effectively against our competitors in the future.

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Our success depends to a significant extent on the continued service of our research and development and engineering personnel, and our ability to continue to attract, retain and motivate qualified technology professionals including researchers and engineers. In particular, our focus on leading the market in introducing new services has meant that we must aggressively recruit technology professionals with expertise in cutting-edge technologies. Such employees are in high demand, and we devote significant resources to identifying, hiring, training, successfully integrating and retaining these employees. Competition for these individuals could cause us to offer higher compensation and other benefits to attract and retain them. We also depend on the services of experienced key senior management, and if we lose their services, it would be difficult to find and integrate replacement personnel in a timely manner, or at all.

The loss of the services of any of our key technology professionals or senior management without adequate replacement, or the inability to attract new qualified personnel, would have a material adverse effect on our results of operations.

If we breach our financial or other covenants, our financial condition will be adversely affected to the extent we are not able to cure such breaches or repay the relevant debt.

We have not arranged firm financing for all of our current or future capital expenditure plans and contractual payment obligations. We have, in the past, obtained funds for our proposed capital expenditure and payment obligations from various sources, including our cash flow from operations as well as from financings, primarily debt and equity financings. Any material adverse change in our operational or financial condition could impact our ability to fund our capital expenditure plans and contractual payment obligations. Volatile financial market conditions and an increasing interest rate environment may also curtail our ability to obtain adequate funding.funding and/or increase our cost of borrowings, which would have an adverse effect on our liquidity and financial position. Inability to fund such capital expenditure requirements may have a material adverse effect on our business, financial condition and results of operations. In addition, although we currently anticipate that the capital expenditure levels estimated by us will be adequate to meet our business needs, such estimates may need to be adjusted based on developments in technology and markets. Failure to meet any such increased expenditure requirements or to obtain adequate financing for such requirements on terms acceptable to us, or at all, may have a material adverse effect on our business, financial condition and results of operations.

We cannot assure you that we will be able to continue to obtain the necessary equipment from one or more of our suppliers. Any discontinuation or interruption in the availability of equipment from our suppliers for any reason could have an adverse effect on our business, financial condition and results of operations. In addition, inability to lease adequate lines at commercially reasonable rates may impact the quality of the services we offer and may also damage our reputation and our business.

We own numerous patents and trademarks worldwide, and have applications for patents pending in many countries. In addition to active research and development efforts, our success depends in part on our ability to obtain patents and other intellectual property rights covering our services.

Our business involves the storage and transmission of large amounts of confidential 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, any of which could harm our reputation and adversely affect our business.

Our cybersecurity measures may also be breached due to employee error, malfeasance or otherwise. Instituting appropriate access controls and safeguards across all of our information technology infrastructure is challenging. Furthermore, outside parties may attempt to fraudulently induce employees to disclose sensitive information in order to gain access to our data or our customers’ data or accounts, or may otherwise obtain access to such data or accounts. Because the techniques used to obtain unauthorized access, disable or degrade service or sabotage systems change frequently and often are not recognized until attacks are launched against a target, we may be unable to anticipate these techniques or to implement adequate preventative measures. While we have experienced minor isolated cybersecurity incidents in the past, we do not believe that any such incidents had a material adverse effect on our business, financial condition or results of operations. If an actual or perceived breach of our cybersecurity of a material nature occurs or the market perception of the effectiveness of our cybersecurity measures is materially harmed, we may incur significant legal and financial exposure, including legal claims and regulatory fines and penalties, damage to our reputation and a loss of confidence of our customers, which could have an adverse effect on our business, financial condition and results of operations.

Although we have never experienced any significant labor disputes, there can be no assurance that we will not experience labor disputes in the future, including protests and strikes, which could have an adverse effect on our business, financial condition and results of operations.

In the past, allegations that serious health risks may result from the use of wireless telecommunications devices or other transmission equipment have adversely affected share prices of some wireless telecommunications companies in the United States. In May 2011, the International Agency for Research on Cancer (the “IARC”), a part of the World Health Organization, announced that it has classified radiofrequency electromagnetic fields associated with wireless phone use as possibly carcinogenic to humans, based on an increased risk for glioma, a malignant type

Our services are currently carried through our wireless and fixed-line networks, which could be vulnerable to damage or interruptions in operations due to fires, floods, earthquakes, power losses, telecommunication failures, network software flaws, unauthorized access, computer viruses and similar events, which may occur from time to time. The occurrence of any of these events could impact our ability to deliver services, we may be liable for damages to our customers caused by such interruptions, our reputation may be damaged and our customers may lose confidence in us, which could have a negative effect on our business, financial condition and results of operations.

Substantially all of our revenues are denominated in Won. Depreciation of the Won may materially affect our results of operations because, among other things, it causes:

Fluctuations in the exchange rate between the Won and the Dollar will affect the Dollar equivalent of the Won price of the our common shares on the KRX KOSPI Market. These fluctuations will also affect:

The Telecommunications Business Act currently sets a 49.0% limit on the aggregate foreign ownership of our issued shares. Under the Telecommunications Business Act, as amended, a Korean entity, such as SK Inc., is deemed to be a foreign entity if its largest shareholder (determined by aggregating the shareholdings of such shareholder and its related parties) is a foreigner and such shareholder (together with the shareholdings of its related parties) holds 15.0% or more of the issued voting stock of the Korean entity.

Notwithstanding the above, pursuant to a recentan amendment to the Telecommunications Business Act which became effective onin April 20, 2022, a Korean entity, so long as (i) such entity’s largest shareholder (determined by aggregating the shareholdings of such shareholder and its related parties) is a foreign entity specifically designated by the MSIT incorporated in a country that has entered into a bilateral or multilateral free trade agreement with Korea, and (ii) such shareholder (together with the shareholdings of its related parties) owns 15.0% or more of the

Relations between Korea and North Korea have been tense throughout Korea’s modern history. The level of tension between the two Koreas has fluctuated and may increase abruptly as a result of future events. In particular, there have been heightened security concerns in recent years stemming from North Korea’s nuclear weapon and ballistic missile programs as well as its hostile military actions against Korea. Some of the significant incidents in recent years include the following:

North Korea’s economy also faces severe challenges, which may further aggravate social and political pressures within North Korea.

Although bilateral summit meetings were held between the two Koreas in April, May and September 2018 and between the United States and North Korea in June 2018, February 2019 and June 2019, there can be no assurance that the level of tensions affecting the Korean peninsula will not escalate in the future. Any increase in tensions, which may occur, for example, if North Korea experiences a leadership crisis, high-level contacts between Korea and North Korea break down or military hostilities occur, could have a material adverse effect on our business, financial condition and results of operations and the market value of our common shares and ADSs.

The Securities-related Class Action Act of Korea enacted in January 2004 allows class action suits to be brought by shareholders of companies (including us) listed on the KRX KOSPI Market for losses incurred in connection with purchases and sales of securities and other securities transactions arising from (1) false or inaccurate statements provided in the registration statements, prospectuses, annual reports, audit reports, and semi-annual or quarterly reports and material fact reports and omissionor omissions of material information in such documents, (2) insider trading, (3) market manipulation and (4) unfair trading. In addition, there are bills currently pending in the National Assembly that would allow for class action suits for losses arising from false or inaccurate statements provided in reports of material facts or omissions of material information in such documents. This law permits 50 or more shareholders who collectively hold 0.01% of the shares of a company to bring a class action suit against, among others, the issuer and its directors and officers. Because of the relatively recent enactment of the act, there is not enough judicial precedent to predict how the courts will apply the law. Litigation can be time-consuming and expensive to resolve, and can divert management time and attention from the operation of a business. We are not aware of any basis upon

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As we are a Korean company and operate in a business and cultural environment that is different from that of other countries, there are risks associated with investing in our securities that are not typical for investments in securities of companies in other jurisdictions.

Under the Korean Foreign Exchange Transactions Act, if the Government deems that certain emergency circumstances, including a significant disruption in the international balance of payments and international financial markets or extreme difficulty in carrying out currency, exchange rate or other macroeconomic policies due to the movement of capital between Korea and other countries, are likely to occur, it may impose any necessary restriction such as requiring Korean or foreign investors to obtain prior approval from the Ministry of Economy and Finance (the “MOEF”) for the acquisition of Korean securities or for the repatriation of interest, dividends or sales proceeds arising from Korean securities or from disposition of such securities or other transactions involving foreign exchange. See “Item 10.D. Exchange Controls — Korean Foreign Exchange Controls and Securities Regulations.”

Sales of substantial amounts of our common shares, or the perception that such sales may occur, could adversely affect the prevailing market value of our common shares or ADSs or our ability to raise capital through an offering of our common shares.

As of December 31, 2021,2022, SK Inc. owned 30.0% of our total issued common shares and has not agreed to any restrictions on its ability to dispose of our shares. See “Item 7.A. Major Shareholders.” We can make no prediction as to the timing or amount of any sales of our common shares. We cannot assure you that future sales of our common shares, or the availability of our common shares for future sale, will not adversely affect the prevailing market value of our common shares or ADSs from time to time.

If we are classified as a PFIC in any taxable year, a U.S. holder (as defined in “Item 10.E. Additional Information — Taxation — United States Federal Income Tax Considerations”) may incur significantly increased U.S. federal income tax on gain recognized on the sale or other disposition of the common shares or ADSs and on the receipt of distributions on the common shares or ADSs to the extent such gain or distribution is treated as an “excess distribution” under the U.S. federal income tax rules, and such U.S. holder may be subject to burdensome reporting requirements. The amount of income tax on any excess distributions will be increased by an interest

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The Korean Commercial Code and our articles of incorporation require us, with some exceptions, to offer shareholders the right to subscribe for new shares in proportion to their existing ownership percentage whenever new shares are issued. If we offer a right to subscribe for additional new common shares or any other rights of similar nature, the ADR depositary, after consultation with us, may make the rights available to an ADS holder or use reasonable efforts to dispose of the rights on behalf of the ADS holder and make the net proceeds available to the ADS holder. The ADR depositary, however, is not required to make available to an ADS holder any rights to purchase any additional shares unless it deems that doing so is lawful and feasible and:

We are under no obligation to file any registration statement with respect to any ADSs. If a registration statement is required for an ADS holder to exercise preemptive rights but is not filed by us, the ADS holder will not be able to exercise his or her preemptive rights for additional shares. As a result, ADS holders may suffer dilution of their equity interest in us.

SK Inc., through one or more special purpose vehicles, has engaged and may in the future engage in monetization transactions relating to its ownership interest in us. These transactions have included and may include

In 2022, 2021 2020 and 2019,2020, our cellular services segment revenue was Won 12,942.3 billion, Won 12,718.5 billion and Won 12,348.0 billion, and Won 12,223.8 billion, respectively, representing 75.9%74.8%, 76.8%75.9% and 79.3%76.8%, respectively, of our consolidated revenue from continuing operations.

We offer wireless voice transmission and data transmission services to our subscribers through our backbone networks. Our wireless telecommunications services are available to our subscribers receiving service under the SK Telecom brand. In addition, customers can obtain wireless telecommunications services that operate on our network from MVNOs that lease our wireless networks. We derive revenues from our wireless telecommunications service principally through monthly plan-based fees as described in “— Rate Plans” below.

In addition, we provide interconnection service to connect our networks to domestic and international fixed-line and other wireless networks. See “— Interconnection” below.

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We offer several categories of wireless devices, including smartphones and basic phones, tablets and other Internet access devices and wearable devices that are sold through an extensive distribution network, which consists of authorized exclusive dealers and independent retailers, as well as branch offices and stores directly operated by us through our wholly-owned subsidiary, PS&Marketing Co., Ltd. (“PS&Marketing”).&Marketing. As of December 31, 2021,2022, approximately 24.524.3 million, or 76.9%74.1%, of our subscribers (including MVNO subscribers leasing our networks) owned smartphones that have direct access to the Internet compared to approximately 23.924.5 million, subscribers, or 76.3%76.9%, as of December 31, 2020.2021, which decrease was primarily due to a faster increase in the number of non-mobile phone wireless devices, such as tablet computers, wearable devices, IoT devices and others, as compared to the increase in the number of smartphones. We purchase a substantial majority of our wireless devices from Samsung Electronics and Apple.

Through our platform services business, we seek to provide innovative AI products and services that meet our customers’ evolving needs in an increasingly connected world. In September 2016, we launched NUGU, the first intelligent AI service launched in Korea with Korean language capabilities based on advanced voice recognition technologies. Through cloud-based deep-learning technology, NUGU is designed to evolve on its own as it collects more data about its users over time.

We offer a variety of smart devices based on NUGU such as the NUGU Candle series, an AI speaker which offers NUGU-based services, “NUGU nemo,” a smart speaker with a touchscreen, “NUGU CHIPS,” a wireless charging dock compatible with certain Samsung Galaxy smartphones that automatically converts the smartphone being charged into a NUGU-capable device, and “albert AI,” an educational device that teaches children how to code.

In recent periods, we have launched a variety of new businesses leveraging our capabilities in telecommunications technology and ICT, and we are continuing to invest in these and other emerging new business areas, including the following:

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We offer our wireless telecommunications services on both a postpaid and prepaid basis. Substantially all of our subscribers received our wireless telecommunications services on a postpaid basis as of December 31, 2021.2022. Postpaid accounts primarily represent retail subscribers under contract with SK Telecom pursuant to which a subscriber is billed in advance a monthly fixed service fee in return for a monthly network service allowance and usage for outgoing voice calls and wireless data services beyond the allowance is billed in arrears, where payment of the total amount of the bill is due at the end of the month. The standard contract period for our rate plans is 24 months, although our subscribers have the option to enter into shorter term contracts or no fixed-term contract at all. We provide various subsidies and discounts, including handset subsidies, depending on the length of the contract and the subscriber’s chosen rate plan. Our prepaid service enables individuals to obtain wireless telecommunications services without a fixed-term contract by paying for all services in advance according to expected usage. We do not charge our customers for incoming calls, although we do receive interconnection charges from KT and other companies for calls from the fixed-line network terminating on our networks and interconnection revenues from other wireless network operators. See “— Interconnection” below.

Our broadband Internet access network covered more than 86%87% of households in Korea as of December 31, 2021.2022. As of December 31, 2021,2022, we had approximately 6.56.7 million broadband Internet access subscribers. We offer broadband Internet access products with various throughput speeds, ranging from “Giga Premium,” which is up to 10 times faster than data transmission speeds on networks utilizing FTTH technology and allows for data transmission at a maximum speed of 1 Gbps, to “Giga Premium×10,” which provides data transmission speeds of up to 10 Gbps.

As part of our initiative to be the leading next-generation platform provider, we provide an advanced media platform with various media content and service offerings.

Following the Tbroad Merger, we also offer cable TV services under the “B tv Cable” brand with access to as many as 220224 channels. As of December 31, 2021,2022, we had approximately 2.92.8 million cable TV subscribers.

We offer other business communications services to our business customers, including corporations and government entities. Our business communications services include leased line solutions, Internet data center solutions and network solution services.

For our residential customers, we offer both bundled rate plans for a combination of our fixed-line service offerings as well as individual rate plans for each separate service offering. Bundled rate plans are offered at a discount compared to subscribing to the same services through individual rate plans. Approximately 86%85% of subscribers to our broadband Internet services subscribe to two or more of our services through our bundled rate plans. Bundled rate plans for a combination of fixed-line telephone, broadband Internet access and IPTV or cable TV services, which are subject to a contract of one to three years, range from Won 30,80019,800 to Won 67,650 per month, depending on the services included and the length of the contract. We also offer bundled rate plans combining our fixed-line communication services with our wireless services and physical security services, respectively.

With respect to our business communications services, we offer rates that are tailored to the specific needs of our business customers. We also charge certain installation fees and equipment rental fees as well as other ancillary fees with respect to certain of our fixed-line telecommunications services.

We focus on bringing our fixed-line telephone, broadband Internet and advanced media platform services (including IPTV and cable TV services) to residential users, and various business communications services to corporate users. We market our fixed-line telecommunications products and services under the “B” brand. Our “B” brand signifies the centrality of “Broadband” to our business and also seeks to emphasize our commitment to providing the “Best” quality products and services to our customers that go “Beyond” expectations, leading to a “Bravo” response. Our “B” brand also strengthens our shared identity with our wireless service’s “T” brand.

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