Cover and table of contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2024

or

For the transition period from to

Commission File Number: 001-07434

Registrant’s telephone number, including area code: 706.323.3431

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. þ Yes ¨ No

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. ¨ Yes þ No

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. þ Yes ¨ No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). þ Yes ¨ No

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and "emerging growth company" in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☑

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). ☐ Yes ☑ No

The aggregate market value of the voting common stock held by non-affiliates of the registrant as of June 28, 2024, was $49,825,613,971.

The number of shares of the registrant’s common stock outstanding at February 18, 2025, with $.10 par value, was 546,588,291.

Documents Incorporated By Reference

Certain information contained in the Notice and Proxy Statement for the Company’s 2025 Annual Meeting of Shareholders is incorporated by reference into Part III hereof.

Aflac Incorporated

Annual Report on Form 10-K

For the Year Ended December 31, 2024

Table of Contents

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Item 1. Business

PART I

FORWARD-LOOKING INFORMATION

The Private Securities Litigation Reform Act of 1995 provides a safe harbor to encourage companies to provide prospective information, so long as those informational statements are identified as forward-looking and are accompanied by meaningful cautionary statements identifying important factors that could cause actual results to differ materially from those included in the forward-looking statements. Aflac Incorporated and its subsidiaries (the Company) desire to take advantage of these provisions. This report contains cautionary statements identifying important factors that could cause actual results to differ materially from those projected herein, and in any other statements made by Company officials in communications with the financial community and contained in documents filed with the Securities and Exchange Commission (SEC). Forward-looking statements are not based on historical information and relate to future operations, strategies, financial results or other developments. Furthermore, forward-looking information is subject to numerous assumptions, risks and uncertainties. In particular, statements containing words such as the ones listed below or similar words, as well as specific projections of future results, generally qualify as forward-looking. The Company undertakes no obligation to update such forward-looking statements.

The Company cautions readers that the following factors, in addition to other factors mentioned from time to time, could cause actual results to differ materially from those contemplated by the forward-looking statements:

• difficult conditions in global capital markets and the economy, including inflation

• defaults and credit downgrades of investments

• global fluctuations in interest rates and exposure to significant interest rate risk

• concentration of business in Japan

• limited availability of acceptable yen-denominated investments

• foreign currency fluctuations in the yen/dollar exchange rate

• differing interpretations applied to investment valuations

• significant valuation judgments in determination of expected credit losses recorded on the Company's investments

• decreases in the Company's financial strength or debt ratings

• decline in creditworthiness of other financial institutions

• the Company's ability to attract and retain qualified sales associates, brokers, employees, and distribution partners

• deviations in actual experience from pricing and reserving assumptions

• ability to continue to develop and implement improvements in information technology systems and on successful execution of revenue growth and expense management initiatives

• interruption in telecommunication, information technology and other operational systems, or a failure to maintain the security, confidentiality, integrity or privacy of sensitive data residing on such systems

• subsidiaries' ability to pay dividends to the Parent Company

• inherent limitations to risk management policies and procedures

• operational risks of third-party vendors

• tax rates applicable to the Company may change

• failure to comply with restrictions on policyholder privacy and information security

• extensive regulation and changes in law or regulation by governmental authorities

• competitive environment and ability to anticipate and respond to market trends

• catastrophic events, including, but not limited to, as a result of climate change, epidemics, pandemics, tornadoes, hurricanes, earthquakes, tsunamis, war or other military action, major public health issues, terrorism or other acts of violence, and damage incidental to such events

• ability to protect the Aflac brand and the Company's reputation

• ability to effectively manage key executive succession

• changes in accounting standards

• level and outcome of litigation or regulatory inquiries

• allegations or determinations of worker misclassification in the United States

Item 1. Business