Item 1. BUSINESS

Aflac Incorporated (the Parent Company) and its subsidiaries (collectively, the Company) prepares its financial statements in accordance with U.S. generally accepted accounting principles (GAAP). This report includes certain forward-looking information that is based on current expectations and is subject to a number of risks and uncertainties. For details on forward-looking information, see Management's Discussion and Analysis of Financial Condition and Results of Operations (MD&A), Part II, Item 7, of this report.

Aflac Incorporated qualifies as a large accelerated filer within the meaning of Rule 12b-2 under the U.S. Securities Exchange Act of 1934 as amended (the Exchange Act). The Company's Internet address is aflac.com. The information on the Company's website is not incorporated by reference in this annual report on Form 10-K. The Company makes available, free of charge on the Investors portion of its website, the Company's annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments thereto as soon as reasonably practicable after those forms have been electronically filed with or furnished to the Securities and Exchange Commission (SEC).

General Description

Aflac Incorporated was incorporated in 1973 under the laws of the state of Georgia. Aflac Incorporated is a general business holding company and acts as a management company, overseeing the operations of its subsidiaries by providing management services and making capital available. Its principal business is voluntary supplemental and life insurance, which is marketed and administered through its subsidiary, American Family Life Assurance Company of Columbus (Aflac), which operates in the United States (Aflac U.S.) and as a branch in Japan (Aflac Japan). Most of Aflac's policies are individually underwritten and marketed through independent agents. Aflac U.S. markets and administers group products through Continental American Insurance Company (CAIC), branded as Aflac Group Insurance. The Company's insurance operations in the United States and its branch in Japan service the two markets for the Company's insurance business.

On December 2, 2016, the Company publicly announced that it will pursue the conversion of Aflac Japan from a branch structure to a subsidiary structure, with the subsidiary incorporated as a “Kabushiki Kaisha.” While the branch structure remains an acceptable legal form, the subsidiary structure has emerged as the more prevalent structure for both domestic and foreign companies operating in Japan. In addition, emerging global regulatory standards generally favor the subsidiary structure for foreign insurance and financial service companies. The adoption of this new organizational framework is expected to be tax-neutral and not to have a material impact on the daily operations of either Aflac Japan or Aflac U.S. as a result of this conversion. In addition, the Company expects to obtain enhanced flexibility in capital management and business development as a result of the conversion. The Company anticipates completion of the conversion as early as April 1, 2018. As an interim step, effective January 1, 2018, investments of Aflac U.S., as well as certain sub-advised assets of Aflac Japan, are managed by the Company’s U.S. asset management subsidiary, Aflac Asset Management LLC (AAM), and investments of Aflac Japan are managed pursuant to an investment advisory agreement with Aflac Japan by the Company’s asset management subsidiary in Japan, Aflac Asset Management Japan Ltd. (AAMJ). AAMJ is licensed as a discretionary asset manager under the Japan Financial Instruments and Exchange Act and is subject to rules of the Japan Investment Advisors Association, a self-regulatory organization with mandatory membership for Japan investment managers.

Aflac offers voluntary insurance policies in Japan and the United States that provide a layer of financial protection against income and asset loss. The Company continues to diversify its product offerings in both Japan and the United States. Aflac Japan sells voluntary supplemental insurance products, including cancer plans, general medical indemnity plans, medical/sickness riders, care plans, living benefit life plans, ordinary life insurance plans and annuities. Aflac U.S. sells voluntary supplemental insurance products including products designed to protect individuals from depletion of assets (accident, cancer, critical illness/care, hospital indemnity, fixed-benefit dental, and vision care plans) and loss-of-income products (life and short-term disability plans).

The Company is authorized to conduct insurance business in all 50 states, the District of Columbia, several U.S. territories and Japan. Aflac Japan's revenues, including realized gains and losses on its investment portfolio, accounted for 70% of the Company's total revenues in 2017, compared with 71% in 2016 and 70% in 2015. The percentage of the Company's total assets attributable to Aflac Japan was 83% at both December 31, 2017 and 2016.

Reporting Segments

Aflac's insurance business consists of two reporting segments: Aflac Japan and Aflac U.S. Aflac Japan, which currently operates as a branch of Aflac, is the principal contributor to the Parent Company’s consolidated earnings. The conversion of Aflac Japan to a subsidiary structure is not expected to affect the Company's segment reporting structure.

For information on the Company's results of operations and financial information by segment, see MD&A and Note 2 of the Notes to the Consolidated Financial Statements in this report.

Foreign Currency Translation

Aflac Japan’s premiums and approximately half of its investment income are received in yen. Claims and most expenses are paid in yen, and the Company purchases yen-denominated assets and U.S. dollar-denominated assets, which may be hedged to yen, to support yen-denominated policy liabilities. These and other yen-denominated financial statement items are, however, translated into U.S. dollars for financial reporting purposes. For information regarding the effect of currency fluctuations on the Company's business, see the Hedging Activities subsection within the Analysis of Financial Condition section of MD&A, the Currency Risk subsection within Quantitative and Qualitative Disclosures about Market Risk, and Notes 1 and 2 of the Notes to the Consolidated Financial Statements in this report. For information regarding how the Company’s investment strategy supports management of foreign currency risk, refer to the Investments subsection below.

Insurance Premiums

The growth of earned premiums is directly affected by the change in premiums in force and by the change in weighted-average yen/dollar exchange rates. Consolidated earned premiums were $18.5 billion in 2017, $19.2 billion in 2016, and $17.6 billion in 2015. For additional information on the composition of earned premiums by segment, see Note 2 of the Notes to the Consolidated Financial Statements in this report. The following table presents the changes in annualized premiums in force for Aflac's insurance business for the years ended December 31.

(In millions)	2017				2016				2015
Annualized premiums in force, beginning of year	$	19,684			$	19,173			$	18,894
New sales, including conversions	2,398				2,527				2,484
Change in unprocessed new sales	26				(46		)		(41		)
Premiums lapsed and surrendered	(2,144		)		(2,102		)		(2,104		)
Other	(606		)		(351		)		(56		)
Foreign currency translation adjustment	429				483				(4		)
Annualized premiums in force, end of year	$	19,787			$	19,684			$	19,173

Japan

The Company translates Aflac Japan's annualized premiums in force into dollars at the respective end-of-period exchange rates. Changes in annualized premiums in force are translated at weighted-average exchange rates. The following table presents the changes in annualized premiums in force for Aflac Japan for the years ended December 31.

	In Dollars												In Yen
(In millions of dollars and billions of yen)	2017				2016				2015				2017			2016			2015
Annualized premiums in force, beginning of year	$	13,788			$	13,413			$	13,226			1,606			1,617			1,594
New sales, including conversions	846				1,045				997				95			114			121
Change in unprocessed new sales	26				(46		)		(41		)		3			(5	)		(5	)
Premiums lapsed and surrendered	(619		)		(623		)		(578		)		(69	)		(68	)		(70	)
Other	(734		)		(484		)		(187		)		(83	)		(52	)		(23	)
Foreign currency translation adjustment	429				483				(4		)		0			0			0
Annualized premiums in force, end of year	$	13,736			$	13,788			$	13,413			1,552			1,606			1,617

For further information regarding Aflac Japan's financial results and sales, see the Aflac Japan Segment subsection of MD&A in this report.

U.S.

The following table presents the changes in annualized premiums in force for Aflac U.S. for the years ended December 31.

(In millions)	2017						2016						2015
Annualized premiums in force, beginning of year		$	5,896					$	5,760					$	5,668
New sales, including conversions		1,552						1,482						1,487
Premiums lapsed		(1,525		)				(1,479		)				(1,526		)
Other		129						133						131
Annualized premiums in force, end of year		$	6,052					$	5,896					$	5,760

For further information regarding Aflac's U.S. financial results and sales, see the Aflac U.S. Segment subsection of MD&A in this report.

Insurance Products

		Aflac Japan				Aflac U.S.
	Third Sector Insurance							Accident
		Cancer						Short-Term Disability
		Medical						Critical Care (1)
		Income Support						Hospital Indemnity
	First Sector Insurance							Dental
		Life						Vision
			Protection					Life (Term, Whole)
				Term
				Whole
			Savings
				WAYS
				Child Endowment

(1) Includes cancer, critical illness, and hospital intensive care products

Japan

Aflac Japan's insurance products are designed to help consumers pay for medical and nonmedical costs that are not reimbursed under Japan's national health insurance system. Changes in Japan's economy and an aging population have put increasing pressure on Japan's national health care system. As a result, more costs have been shifted to Japanese consumers, who in turn have become increasingly interested in insurance products that help them manage those costs. Aflac Japan has responded to this consumer need by enhancing existing products and developing new products.

The foundation of Aflac Japan's product portfolio has been, and continues to be, its third sector cancer and medical insurance products. Aflac pioneered the cancer insurance market in Japan in 1974, and remains the number one provider of cancer insurance in Japan today. Over the years, Aflac Japan has customized its cancer insurance product to respond to, and anticipate, the needs of its consumers and the advances in medical treatments. The cancer insurance plans the Company offers in Japan provide a lump-sum benefit upon initial diagnosis of internal cancer and benefits for treatment received due to internal cancer such as fixed daily benefits for hospitalization, outpatient services and convalescent care, and surgical benefits. In September 2014, Aflac Japan introduced New Cancer DAYS, a new cancer insurance product which provides enhanced coverage, including outpatient treatments and multiple cancer occurrence benefits. At the same time, premiums for this product have been lowered for most ages compared to prior plans. In October 2014, Aflac Japan introduced a unique Aflac-branded cancer insurance product for Japan's postal system, Japan Post (see the Distribution - Japan section for background information). In March 2016, Aflac Japan launched a cancer insurance product that offers protection to customers who have survived cancer. As the number one provider of cancer insurance in Japan, the Company believes these products further strengthen its brand, and most importantly, provide valuable benefits to consumers who are looking for solutions to manage cancer-related costs.

In early 2002, Aflac Japan introduced EVER, a stand-alone, whole-life medical insurance product which offers a basic level of hospitalization coverage with an affordable premium. Since its initial introduction, Aflac Japan has expanded its suite of EVER product offerings to appeal to specific types of Japanese consumers and achieve greater market penetration. In June 2015, Aflac Japan upgraded its EVER insurance product to include riders to be associated with three critical illnesses (cancer, heart attack, and stroke) to better respond to consumer’s needs for coverage of serious illnesses. These riders provide policyholders with a benefit upon the diagnosis for those three critical illnesses, waiver of premium payment thereafter and unlimited hospital days for such critical illnesses. In 2007, Gentle EVER, Aflac Japan's non-standard medical insurance product, was introduced. This product was designed to meet the needs of certain consumers who cannot qualify for the base EVER plan. The latest version was introduced in March 2016 to enhance its alignment with changing customer needs. In February 2017, Aflac Japan revised the EVER product by introducing riders for lump-sum hospitalization benefits and surgeries for female-specific diseases as well as strengthening outpatient benefits and reducing premiums centered on the young- to middle-aged market segments. This product also offers a short-pay premium period to policyholders.

The Company believes that the affordable cancer and medical insurance products Aflac Japan provides will continue to be an important part of its product portfolio. Nevertheless, as the Company continues its long history of product innovation, Aflac Japan's product portfolio has expanded beyond traditional health-related products.

In July 2016, Aflac Japan launched a new third sector product called Income Support Insurance. This product provides fixed-benefit amounts in the event that a policyholder is unable to work due to significant illness or injury and was developed to supplement the disability coverage within Japan’s social security system. This product targets young to middle-aged consumers, and by focusing efforts on this demographic, Aflac Japan believes it is building relationships that lay the groundwork for the sale of its cancer and medical insurance later in life to the Income Support policyholders.

While Aflac Japan continues to offer life insurance and other first sector products, Aflac Japan has decreased sales of first sector savings products, such as WAYS, child endowment and annuities, in light of the negative interest-rate environment in Japan. Aflac Japan continues to monitor interest rates and their effects on its first sector business. Aflac Japan believes that the measures taken to date, including lowering assumed interest rates or increasing premiums, are appropriate in response to interest rates and that life insurance continues to provide cross-selling opportunities for its third sector products such as cancer and medical insurance. Some of the life insurance products that the Company offers in Japan provide death benefits and cash surrender values. These products are available as stand-alone policies and riders, providing a mix of term and whole life coverage. Aflac Japan's WAYS insurance product has features that allow policyholders to convert a portion of their life insurance to medical, nursing care, or fixed annuity benefits at a predetermined age. In November 2016, Aflac Japan lowered the assumed interest rate for WAYS reflecting the continued low interest rate environment, consistent with its desire to de-emphasize first-sector sales and bolster profitability. Also in November 2016, Aflac Japan halted the offering of traditional fixed-income annuities. Aflac Japan's child endowment insurance product offers a death benefit until a child reaches age 18. It also pays a lump-sum benefit at the time of the child's entry into high school, as well as an educational annuity for each of the four years during his or her college education. In January 2017, Aflac Japan increased the premium level of this product reflecting the continued low interest rate environment.

Aflac Japan continues to proactively sell first sector protection-type products, which include term and whole life, to provide Aflac Japan’s traditional sales channels with a more comprehensive product portfolio to continue to cross-sell with third sector products.

For additional information on Aflac Japan's products and composition of sales, see the Aflac Japan Segment subsection of MD&A in this report.

U.S.

The Company designs its U.S. insurance products to provide supplemental coverage for people who already have major medical or primary insurance coverage. Most of Aflac's U.S. policies are individually underwritten and marketed through independent agents. Additionally, Aflac U.S. started to market and administer group insurance products in 2009.

Aflac U.S. insurance policies pay benefits regardless of other insurance. Most of the Aflac U.S. insurance benefits are paid in cash directly to policyholders; therefore, customers have the opportunity to use this cash to help with expenses of their choosing. Aflac U.S. individually issued policies are portable and are typically guaranteed-renewable for the lifetime of the policyholder (to age 75 for short-term disability policies). Aflac U.S. group insurance policies are underwritten on a group basis and often have some element of guaranteed issue.

Aflac U.S. offers accident coverage on both an individual and group basis. These policies are designed to protect against losses resulting from accidents. The accident portion of the policy includes lump-sum benefits for accidental death, dismemberment and specific injuries as well as fixed benefits for hospital confinement. Additional benefits are also available for home modifications, wellness and increased benefits for injuries related to participations in an organized sporting activity.

Aflac U.S. offers short-term disability benefits on both an individual and group basis. The individual short-term disability product has an Aflac Value Rider that pays a benefit, less claims, for every consecutive five-year term that the policy is in force.

Aflac U.S. offers coverage for critical care on both an individual and group basis. These policies are designed to protect against losses resulting from critical illnesses such as heart attack, stroke, or cancer. On an individually underwritten basis, Aflac U.S. offers cancer plans, critical illness plans, and critical care and recovery plans (formerly called specified health event). On a group basis Aflac U.S. offers critical illness plans.

Aflac U.S. offers hospital indemnity coverage on both an individual and group basis. Hospital indemnity products provide policyholders fixed dollar benefits triggered by hospitalization due to accident or sickness, or just sickness alone. Indemnity benefits for inpatient and outpatient surgeries, as well as various other diagnostic events, are also available. Aflac U.S. also offers a lump sum rider that can be added to its individual accident, short-term disability and hospital indemnity products. This rider, where available, provides a lump sum payment for a range of critical illness events including traumatic brain injury, Type 1 diabetes, advanced Alzheimer’s disease and many more. In January 2016, a new group hospital indemnity plan was introduced that includes 11 new benefits, including telemedicine and health screening. This plan provides flexibility, allowing the Company's clients to personalize their plan designs to complement the underlying medical coverage that is offered to employees.

Aflac U.S. offers additional coverages to those listed above, including dental, vision and life policies. Aflac U.S. offers fixed-benefit dental coverage on both an individual and group basis. Aflac U.S. offers Vision NowSM, an individually issued policy which provides benefits for serious eye health conditions and loss of sight as well as coverage for corrective eye materials and exam benefits. Aflac U.S. also offers term- and whole-life policies on both an individual and group basis.

For additional information on Aflac's U.S. products and composition of sales, see the Aflac U.S. Segment subsection of MD&A in this report.

Distribution Channels

	Aflac Japan		Aflac U.S.
	Individual/ Independent Corporate Agencies		Independent Associates
	Affiliated Corporate Agencies		Brokers
	Banks

Japan

The traditional channels through which Aflac Japan has sold its products consist of individual agents/agencies, independent corporate agencies, and affiliated corporate agencies. The individual agencies and independent corporate agencies that sell Aflac Japan's products give better access to workers at a vast number of small businesses in Japan. Agents' activities are primarily focused on insurance sales, with customer service support provided by the Aflac Contact Center. Affiliated corporate agencies are originally formed when companies establish subsidiary businesses to sell Aflac Japan's insurance products to its employees as part of a benefit package, and then expand to sell Aflac Japan products to other parties such as suppliers and customers.These agencies help Aflac Japan reach employees at large worksites, and some of them are also successful in approaching customers outside their business groups. The Company believes that new agencies will continue to be attracted to Aflac Japan's competitive commissions, attractive products, superior customer service and strong brand image.

The Company has sold products to employees of banks since its entry into Japan in 1974. However, December 2007 marked the first time it was permissible for banks to sell Aflac Japan's type of insurance products to their customers. By the end of 2017, Aflac Japan had agreements with approximately 90% of the total number of banks in Japan, to sell its products. The Company believes Aflac Japan has more banks selling its supplemental health insurance products than any of its competitors. Japanese consumers rely on banks to provide traditional bank services, and also to provide insurance solutions and other services. The Company believes Aflac Japan's long-standing and strong relationships within the

Japanese banking sector, along with its strategic preparations, have proven to be an advantage, particularly starting when this channel opened up for its products. Aflac Japan's partnerships throughout the banking sector provide Aflac Japan with a wider demographic of potential customers than it would otherwise have been able to reach, and it also allows banks to expand their product and service offerings to consumers.

In 2005, legislation aimed at privatizing Japan's postal system (Japan Post) was enacted into law. The privatization laws split Japan Post into four operating entities that began operating in October 2007. In 2007, one of these entities selected Aflac Japan as its provider of cancer insurance to be sold through its post offices, and, in 2008, Aflac Japan began selling cancer insurance through these post offices. Japan Post has historically been a popular place for consumers to purchase insurance products. Legislation to reform the postal system passed Japan’s legislature, the Diet, in April 2012 and resulted in the merger of two of the postal operating entities (the one that delivers the mail and the one that runs the post offices) in October 2012. In July 2013, Aflac Japan entered into a new agreement with Japan Post Holdings to further expand the partnership that was established in 2008. At the end of June 2014, Japan Post Insurance (Kampo) received approval from Japan’s primary insurance regulator, the Financial Services Agency (FSA), to enter into an agency contract with Aflac Japan to begin distributing Aflac Japan's cancer insurance products through all of Kampo's 79 directly managed sales offices. Aflac Japan has developed a unique Aflac-branded cancer insurance product for Japan Post and Kampo that was introduced in October 2014. In the fourth quarter of 2014, the number of postal outlets selling the Company's cancer insurance products expanded to approximately 10,000, and beginning in July 2015, Japan Post expanded the number of post offices that offer Aflac's cancer insurance products to more than 20,000 postal outlets. The Company believes this alliance with Japan Post, which is included in Aflac Japan's affiliated corporate agencies distribution channel, has benefited and will continue to benefit Aflac Japan's cancer insurance sales.

For additional information on Aflac Japan's distribution, see the Aflac Japan Segment subsection of MD&A in this report.

U.S.

As of December 31, 2017, the U.S. sales force was composed of sales associates and brokers who are licensed to sell accident and health insurance. Many are also licensed to sell life insurance. Aflac U.S. utilizes dual-channel distribution to market its insurance products to businesses of all sizes. The career agent channel focuses on marketing Aflac to the small business market, which consists of employers with less than 100 employees. As such, Aflac U.S. has aligned its recruiting, training, compensation, marketing and incentives for its career agents to encourage specific activity and sales of individual policies in this market. The broker channel focuses on selling to the mid- and large-case market, which is comprised of employers with more than 100 employees and typically an average size of 1,000 employees or more. Since regional and national brokers have traditionally served the mid- and large-case market, the highly trained and experienced sales professionals of the broker channel are assigned a geographic market to strengthen relationships with the top brokers and sell Aflac products to their clients. As a result, Aflac U.S. is represented on 160 benefit administration platforms, sometimes referred to as exchanges, of various brokers.

Sales associates and brokers are independent contractors and are paid commissions based on first-year and renewal premiums from their sales of insurance products. In addition to receiving commissions on personal production, district and regional sales coordinators may also receive override commissions and incentive bonuses.

Aflac U.S. has continued to evolve its career and broker management infrastructure to drive growth in sales. In 2017, Aflac hired a Chief Distribution Officer to align the strategies of career and broker channels and to further expand U.S. distribution. All Aflac U.S. sales channels are now within the organizational structure of the Chief Distribution Officer. Prior to this change, the broker and career channels were part of separate organizational structures. Aflac U.S. believes the addition of this role will enhance performance management and augment its long-term sales strategy.

Aflac U.S. concentrates on marketing its insurance products at the worksite. This method offers policies to individuals through employment, trade and other associations. Historically, Aflac U.S. policies have been individually underwritten, however over the past several years, guaranteed issue options have become available. Premiums are generally paid by the employee. Additionally, Aflac's individual policies are portable, meaning that individuals may retain their full insurance coverage upon separation from employment or such affiliation, generally at the same premium. Aflac U.S. collects a major portion of premiums on such sales through payroll deduction or other forms of centralized billing. With Aflac U.S. brokerage sales expansion and CAIC, branded as Aflac Group Insurance, Aflac U.S. offers group voluntary insurance products desired by many large employers. These products are sold on a group basis and often have some element of guaranteed issue. Worksite marketing enables sales associates and brokers to reach a greater number of prospective policyholders and lowers distribution costs, compared with individually marketed business.

For additional information on Aflac's U.S. distribution, see the Aflac U.S. Segment subsection of MD&A in this report.

Competition

Japan

In 1974, Aflac was granted an operating license to sell life insurance in Japan, making Aflac the second non-Japanese life insurance company to gain direct access to the Japanese insurance market. Through 1981, Aflac Japan faced limited competition for cancer insurance policy sales. However, Japan has experienced two periods of deregulation since Aflac Japan entered the market. The first came in the early 1980s, when nine mid-sized insurers, including domestic and foreign companies, were allowed to sell cancer insurance products for the first time. The second period began in 2001 when all life and non-life insurers were allowed to sell stand-alone cancer and medical insurance products as well as other stand-alone health insurance products. As a result, the number of insurance companies offering stand-alone cancer and medical insurance has more than doubled since the market was deregulated in 2001. However, based on Aflac Japan's growth of annualized premiums in force and agencies, the Company does not believe that Aflac Japan's market-leading position has been significantly impacted by increased competition. Furthermore, the Company believes the continued development and maintenance of operating efficiencies will allow Aflac Japan to offer affordable products that appeal to consumers. Aflac is the largest life insurer in Japan in terms of cancer and medical policies in force. As of December 31, 2017, Aflac Japan exceeded 24 million individual policies in force in Japan.

Aflac has had substantial success selling cancer policies in Japan, with more than 15 million cancer policies in force as of December 31, 2017. Aflac continued to be the number one seller of cancer insurance policies in Japan throughout 2017. The Company believes Aflac Japan will remain a leading provider of cancer insurance coverage in Japan, principally due to its experience in the market, well-known brand, low-cost operations, expansive marketing system (see Distribution - Japan above) and product expertise.

Aflac Japan has also experienced substantial success selling medical insurance in Japan. While other companies have recognized the opportunities that Aflac Japan has seen in the medical insurance market and offered new products, Aflac Japan endeavors to make its products stand out for their value to consumers.

U.S.

Aflac competes against several voluntary supplemental insurance carriers on a national and regional basis. Aflac U.S. believes its policies, premium rates, platforms, value-added services and sales commissions are competitive by product type. Moreover, Aflac U.S. believes that Aflac products are distinct from competitive offerings given its product focus (including features, benefits, and its claims service model), distribution capabilities, and brand awareness. For many companies with which Aflac U.S. competes, voluntary supplemental insurance products are sold as a secondary business. A growing number of major medical and life insurance carriers are also entering into the voluntary supplemental insurance market. For Aflac U.S., supplemental insurance products are its primary business and are sold via a distribution network of independent sales associates and brokers (see U.S. Distribution above). In addition, the Company believes that advertising campaigns for Aflac U.S. have increased name awareness and understanding among consumers and businesses of the value its products provide.

Both private and publicly-traded insurers offer major medical insurance for hospitalization and medical expenses. Much of this insurance is sold on a group basis to accounts that are both fully and self-insured. The federal and state governments also pay substantial costs of medical treatment through various programs. Major medical insurance generally covers a substantial portion of the medical expenses incurred by an insured. Aflac policies are designed to provide coverage that supplements major medical insurance by paying cash directly to the policyholder to use for expenses their major medical insurance is not designed to cover, or for any other uses that the policyholder chooses. Thus, Aflac U.S. does not compete directly with major medical insurers except those who sell supplemental insurance products as a secondary business. Any reduction of coverage, increase in employee participation costs, or increased deductibles and copayments by major medical commercial or government insurance carriers could favorably affect Aflac U.S. business opportunities. Since the implementation of the Affordable Care Act (ACA) beginning in 2010, some employers have shifted a larger burden of the cost of care to their employees, primarily through increases in premiums, copays, and/or deductibles, such as through the use of high-deductible health plans. In addition, the Company believes that some employers have made increasing use of supplemental insurance product offerings in order to improve their competitiveness in employee recruitment and retention.

Since Aflac products provide an additional level of financial protection for policyholders, the Company believes the increased financial exposure some employees may face creates a favorable opportunity for Aflac U.S. products. However, given the profitability erosion some major medical carriers are facing in their core lines of business, the Company has seen a more competitive landscape as they seek entry into Aflac's supplemental product segments and leverage their core benefit offerings by bundling and discounting products in order to gain voluntary market share.

One Day PaySM is a claims initiative that Aflac U.S. introduced in 2015 to process, approve and pay eligible claims in just one day. The Company believes that along with its brand and relevant products, this claims practice has helped Aflac stand out from competitors.

Investments

Japan

The Company’s investment strategy with respect to Aflac Japan utilizes disciplined asset and liability management while seeking diversification, long-term risk-adjusted investment returns and the delivery of stable income within regulatory and capital objectives, as well as preserving shareholder value in the Aflac Japan business.

In attempting to optimally balance these objectives, the Company seeks to maintain on behalf of Aflac Japan a diversified portfolio of yen-denominated investment assets, U.S. dollar-denominated investment portfolio hedged back to yen and a portfolio of unhedged U.S. dollar-denominated assets. Each of these portfolios presents unique benefits and risks to the Company.

Yen-denominated investments included in Aflac Japan’s portfolio primarily consist of Japan Government Bonds (JGB), other public bonds and private placement fixed income instruments. The Company attempts to match both the duration and currency of these assets with Aflac Japan’s liabilities. This poses a difficulty in Aflac Japan due to the lack of suitable long-dated yen-denominated fixed income instruments. In 2012, the Company initiated a strategic approach to include U.S. dollar-denominated investments in Aflac Japan’s portfolio with the initial intent that they would be coupled with foreign exchange hedges. Today, this hedged U.S. dollar-denominated investment portfolio is mainly invested in long-term fixed and floating-rate loans and long-term investment-grade and high-yield fixed income securities. The primary goals of the yen-denominated and hedged U.S. dollar portfolios are to provide sufficient yen cash flows to support the insurance liabilities and other yen-denominated obligations of Aflac Japan, and to seek appropriate long-term risk-adjusted investment returns supportive of solvency margin ratio (SMR) levels that provide sufficient repatriation and dividend flows to the Parent Company. The hedges supporting this portion of the U.S.-dollar portfolio pose derivative rollover risk that could amplify hedge costs in unfavorable market conditions, risk of counterparty default, and may require the Company to post collateral. In a declining yen environment, these hedges are attended by negative cash settlements that may significantly increase liquidity requirements, thereby shifting funds away from other capital management opportunities including loss of investment income. If over long term the combined yen-denominated and hedged U.S.-dollar portfolios are too large relative to the Aflac Japan’s yen obligations, this may erode the economic value of these portfolios under a long-term scenario of weakening yen due to foreign currency translation risk which may emerge over time in the form of reduced repatriation and dividend capacity.

The Company also maintains an unhedged U.S. dollar-denominated investment portfolio with the objectives of generating enhanced investment returns and mitigating certain of the risks posed by the yen and hedged U.S. dollar-denominated portfolios as outlined above. Further, the Company has determined that the unhedged portfolio acts as a natural economic currency hedge of a portion of the Company’s investment in Aflac Japan against erosion of economic value. However, the unhedged U.S. dollar-denominated investment portfolio creates an unmatched foreign currency exposure and subjects Aflac Japan to volatility in regulatory capital and earnings, which may adversely impact Aflac Japan’s ability to pay dividends to the Parent Company. The Company’s approach to sizing the unhedged U.S. dollar-denominated investment portfolio seeks to balance the unique risks presented by each of the three portfolios outlined above, but the overall investment strategy in Aflac Japan is guided primarily by the objective of securing the long-term financial strength of Aflac Japan and funding of yen liabilities. As a result, the Company has historically maintained and currently maintains the size of the unhedged portfolio at levels below the stressed economic surplus in Aflac Japan.

The determination of stressed economic surplus in Aflac Japan involves multiple models using multiple statistical approaches and assuming various economic and operating scenarios that are stressed to arrive at a range of potential outcomes. This range does not account for all economic scenarios, some of which may result in values outside of the range. The Company periodically assesses the stressed economic surplus in Aflac Japan, which fluctuates over time, and adjusts the size of the unhedged portfolio accordingly. The portfolio may include medium-term and long-term fixed-rate government and corporate (investment-grade and high-yield) bonds, floating-rate loans, public equities, and alternative

asset classes. In determining the composition of the portfolio, the Company also considers diversification, hedge cost, investment returns relative to yen-denominated investment yields, and Aflac Japan capital requirements. At December 31, 2017, this unhedged U.S. dollar-denominated portfolio was approximately $13.0 billion, compared with approximately $8.6 billion at December 31, 2016. For additional discussion of business and market risks associated with the Company’s investment strategy in Japan, refer to the Risk Factors and Quantitative and Qualitative Disclosures about Market Risk sections.

U.S.

The Company’s investment strategy with respect to Aflac U.S. utilizes disciplined asset and liability management while seeking long-term risk-adjusted investment returns and the delivery of stable income within regulatory and capital objectives. As part of the Company's portfolio management and asset allocation process, Aflac U.S. invests in fixed-maturity investments and growth assets, including public equities and alternative investments in limited partnerships. Aflac U.S. has been investing in both publicly traded and privately originated investment-grade and below-investment-grade fixed-maturity securities and loans.

For further information on the Company's investments and investment results, see the Insurance Operations and Analysis of Financial Condition sections of MD&A and Notes 3, 4 and 5 of the Notes to the Consolidated Financial Statements in this report.

Regulation

Japan

The financial and business affairs of Aflac Japan are subject to examination by Japan's FSA. Aflac Japan files annual reports and financial statements for the Japanese insurance operations based on a March 31 fiscal year end, prepared in accordance with Japanese regulatory accounting practices prescribed or permitted by the FSA. Japanese regulatory basis earnings are determined using accounting principles that differ materially from U.S. GAAP. For example, under Japanese regulatory accounting practices, policy acquisition costs are expensed immediately; policy benefit and claim reserving methods and assumptions are different; premium income is recognized on a cash basis; different consolidation criteria apply to variable interest entities (VIEs); different accounting applies to reinsurance; and investments can have a separate accounting classification and treatment referred to as policy reserve matching bonds (PRM). Capital and surplus of Aflac Japan, based on Japanese regulatory accounting practices, was $6.7 billion at December 31, 2017, compared with $5.6 billion at December 31, 2016.

The FSA maintains a solvency standard, which is used by Japanese regulators to monitor the financial strength of insurance companies. As of December 31, 2017, Aflac Japan's SMR was 1,064%, compared with 945% at December 31, 2016. Aflac Japan's SMR is sensitive to interest rate, credit spread and foreign exchange rate changes. See the Capital Resources and Liquidity Section of MD&A for a discussion of measures the Company has taken to mitigate the sensitivity of Aflac Japan's SMR.

Aflac Japan typically repatriates a portion of its accumulated earnings, as determined on a Japanese regulatory accounting basis, to Aflac U.S. provided that Aflac Japan has determined that it adequately protected policyholders' interests as measured by its SMR. The FSA may not allow profit repatriations to Aflac U.S. if the transfers would cause Aflac Japan to lack sufficient financial strength for the protection of Japanese policyholders. In the near term, the Company does not expect these requirements to adversely affect the funds available for profit repatriations, nor does the Company expect these requirements to adversely affect the funds available for payments of allocated expenses to Aflac U.S. and management fees to the Parent Company. Upon conversion of Aflac Japan to a subsidiary structure, which the Company anticipates completing as early as April 1, 2018, the new subsidiary will distribute dividends instead of internal profit repatriation. Such dividends will be subject to permitted dividend capacity under the Japan Company Law.

The Japanese insurance industry has a policyholder protection corporation that provides funds for the policyholders of insolvent insurers. For additional information regarding the policyholder protection fund, see the Policyholder Protection subsection of MD&A in this report.

In June 2013, a revision to the Financial Instruments and Exchange Act established a post-funded Orderly Resolution Regime for financial institutions to prevent a financial crisis in the event of a financial institution’s failure. This regime came into effect in March 2014 and has not had, and is not expected to have, a material impact on the Company's operations in Japan.

As a branch of Aflac's principal insurance subsidiary, Aflac Japan is also subject to regulation and supervision in the United States (see U.S. Regulation below). For additional information regarding Aflac Japan's operations and regulations, see the Aflac Japan Segment subsection of MD&A and Notes 2 and 13 of the Notes to the Consolidated Financial Statements in this report.

U.S.

General

The Parent Company and its insurance subsidiaries, Aflac (a Nebraska-domiciled insurance company), American Family Life Assurance Company of New York (Aflac New York, a New York-domiciled insurance company) and CAIC (redomiciled from South Carolina to Nebraska effective December 2016) are subject to state regulations in the United States as an insurance holding company system. Such regulations generally provide that transactions between companies within the holding company system must be fair and equitable. In addition, transfers of assets among such affiliated companies, certain dividend payments from insurance subsidiaries, and material transactions between companies within the system, including management fees, loans and advances are subject to prior notice to, or approval by, state regulatory authorities. These laws generally require, among other things, the insurance holding company and each insurance company directly owned by the holding company to register with the insurance departments of their respective domiciliary states and to furnish annually financial and other information about the operations of companies within the holding company system.

Like all U.S. insurance companies, Aflac is subject to regulation and supervision in the jurisdictions in which it does business. In general, the insurance laws of the various jurisdictions establish supervisory agencies with broad administrative powers relating to, among other things:

•	granting and revoking licenses to transact business

•	regulating trade and claims practices

•	licensing of insurance agents and brokers

•	approval of policy forms and premium rates

•	standards of solvency and maintenance of specified policy benefit reserves and minimum loss ratio requirements

•	capital requirements

•	limitations on dividends to shareholders

•	the nature of and limitations on investments

•	deposits of securities for the benefit of policyholders

•	filing of financial statements prepared in accordance with statutory insurance accounting practices prescribed or permitted by regulatory authorities

•	periodic examinations of the market conduct, financial, and other affairs of insurance companies

The insurance laws of Nebraska that govern Aflac's activities provide that the acquisition or change of “control” of a domestic insurer or of any person that controls a domestic insurer cannot be consummated without the prior approval of the Nebraska Department of Insurance. A person seeking to acquire control, directly or indirectly, of a domestic insurance company or of any person controlling a domestic insurance company (in the case of Aflac, the Parent Company) must generally file with the Nebraska Department of Insurance (NDOI) an application for change of control containing certain information required by statute and published regulations and provide a copy to Aflac. In Nebraska, control is generally presumed to exist if any person, directly or indirectly, acquires 10% or more of an insurance company or of any other person or entity controlling the insurance company. The 10% presumption is not conclusive and control may be found to exist at less than 10%. Similar laws apply in New York, the domiciliary jurisdiction of Aflac's New York insurance subsidiary.

State insurance departments conduct periodic examinations of the books and records, financial reporting, policy filings and market conduct of insurance companies domiciled in their states, generally once every three to five years. Examinations are generally carried out in cooperation with the insurance departments of other states under guidelines promulgated by the National Association of Insurance Commissioners (NAIC). In 2016, full-scope, risk-focused financial examinations were conducted by the NDOI, New York Department of Financial Services (NYDFS), and the South Carolina Department of Insurance (SCDOI) on their state domiciled insurance entities American Family Life Assurance Company of Columbus, American Family Life Assurance Company of New York, and Continental American Insurance Company, respectively. The NDOI and NYDFS exams covered a four-year period ending December 31, 2015, whereas the SCDOI

exam covered a five-year period ending December 31, 2015. There were no material findings contained in the NDOI, NYDFS and SCDOI final exam reports.

The NAIC continually reviews regulatory matters, such as risk-based capital (RBC) modernization and principle-based reserving, and recommends changes and revisions for adoption by state legislators and insurance departments. The NAIC has adopted a valuation manual containing a principle-based approach to calculation of life insurance reserves. The valuation manual became effective January 1, 2017. There is a three-year transition period, beginning January 1, 2017, during which companies can choose, on a product by product basis to implement principle-based reserving for new business. There will be no material impact on our statutory reserves. The NAIC uses a risk-based capital formula relating to insurance risk, business risk, asset risk and interest rate risk to facilitate identification by insurance regulators of inadequately capitalized insurance companies based upon the types and mix of risk inherent in the insurer's operations. The formulas for determining the amount of risk-based capital specify various weighting factors that are applied to financial balances or various levels of activity based on the perceived degree of risk. Regulatory compliance is determined by a ratio of a company's regulatory total adjusted capital to its authorized control level risk-based capital as defined by the NAIC. Companies below specific trigger points or ratios are classified within certain levels, each of which requires specified corrective action. The levels are company action, regulatory action, authorized control, and mandatory control. Aflac's NAIC risk-based capital ratio remains high and reflects a very strong capital and surplus position. As of December 31, 2017, based on year-end statutory accounting results, Aflac's company action level RBC ratio was 831%.

Under state insurance guaranty association laws and similar laws in international jurisdictions, the Company is subject to assessments, based on the share of business the Company writes in the relevant jurisdiction, for certain obligations of insolvent insurance companies to policyholders and claimants. In the United States, some states permit member insurers to recover assessments paid through full or partial premium tax offsets. The Company's policy is to accrue assessments when the entity for which the insolvency relates has met its state of domicile's statutory definition of insolvency, the amount of the loss is reasonably estimable and the related premium upon which the assessment is based is written. In most states, the definition is met with a declaration of financial insolvency by a court of competent jurisdiction. For additional information regarding state insurance guaranty assessments, see the U.S. Regulatory Environment subsection of MD&A in this report.

Healthcare Reform Legislation

Federal legislation and administrative policies in several areas, including health care reform legislation, financial services reform legislation, securities regulation, pension regulation, privacy, tort reform legislation and taxation, can significantly and adversely affect insurance companies. For example, the ACA, federal health care reform legislation, gave the U.S. federal government direct regulatory authority over the business of health insurance. The reform included major changes to the U.S. health care insurance marketplace. Among other changes, the reform legislation included an individual medical insurance coverage mandate (which has since been repealed effective 2019 by the Tax Act, discussed below), provided for penalties on certain employers for failing to provide adequate coverage, created health insurance exchanges, and addressed coverage and exclusions as well as medical loss ratios. It also imposed an excise tax on certain high cost plans, known as the “Cadillac tax,” that is currently scheduled to begin in 2020. The legislation also included changes in government reimbursements and tax credits for individuals and employers and alters federal and state regulation of health insurers. The ACA, as enacted, does not require material changes in the design of the Company's insurance products. However, indirect consequences of the legislation and regulations could present challenges that could potentially have an impact on the Company's sales model, financial condition and results of operations. The United States Congress has considered and may continue to consider legislation that would repeal and replace key provisions of the ACA. There can be no assurance that any legislation affecting the ACA will be passed by Congress, nor as to the ultimate timing or provisions of any such legislation, nor as to the effect of any such legislation on the design or marketability of the Company's insurance products.

Tax Reform Legislation

A budget reconciliation act commonly referred to as the Tax Cuts and Job Act (Tax Act) was signed into law on December 22, 2017. Among other things, effective January 1, 2018, the Tax Act reduced the U.S. federal statutory corporate income tax rate from 35% to 21%, eliminated or reduced certain deductions and credits, and limited the deductibility of interest expense and executive compensation.

The Tax Act also transitions international corporate taxation from a worldwide system to a modified territorial system, which in light of the current tax treatment of Aflac Japan as a branch has the effect of subjecting the earnings of Aflac Japan to Japan taxation and subjecting the Company’s other earnings, including the consolidated earnings of the Parent Company, to U.S. taxation. The treatment of Aflac Japan as a branch for U.S. tax purposes is not expected to change

upon the completion of its conversion from a branch structure to a subsidiary structure, which conversion is currently anticipated to be completed as early as April 1, 2018.

These changes are effective on January 1, 2018. Because changes to tax rates are accounted for in the period of enactment, during the period ended December 31, 2017, the Company revalued its deferred tax assets and liabilities and recorded, as the Company’s reasonable estimate, a net deferred tax liability reduction of $1.9 billion as of that date. For information on the effects of the Tax Act during the period ended December 31, 2017, see Note 10 of the Notes to the Consolidated Financial Statements presented in this report. For information on the conversion of Aflac Japan from a branch to a subsidiary, see General Business under this Business section, above.

Dodd-Frank Act

Title VII of the Dodd-Frank Act and regulations issued thereunder, in particular rules to require central clearing for certain types of derivatives, may have an impact on Aflac's derivative activity, including activity on behalf of Aflac Japan. In addition, in 2015 and 2016, six U.S. financial regulators, including the U.S. Commodity Futures Trading Commission (CFTC), issued final rules regarding the exchange of initial margin (IM) and variation margin (VM) for uncleared swaps that impose greater obligations on swap dealers regarding uncleared swaps with certain counterparties, such as Aflac. The requirements of such rules with respect to VM, as well as similar regulations in Europe, became effective on March 1, 2017. Full compliance with respect to all counterparties was required by September 1, 2017. The requirements of such rules with respect to IM are currently being phased in and will be fully implemented by September 1, 2020. In October of 2017, the CFTC and the European Commission each finalized comparability determinations that permit certain swap dealers who are subject to both regulatory margin regimes to take advantage of substituted compliance by complying with one set of margin requirements. The margin requirements are expected to result in more stringent collateral requirements and to affect other aspects of Aflac's derivatives activity.

The Dodd-Frank Act also established a Federal Insurance Office (FIO) under the U.S. Treasury Department to monitor all aspects of the insurance industry and of lines of business other than certain health insurance, certain long-term care insurance and crop insurance. Traditionally, U.S. insurance companies have been regulated primarily by state insurance departments. The FIO does not directly regulate the insurance industry, but under Dodd Frank it has the power to preempt state insurance regulations that are inconsistent with international agreements reached by the federal government, subject to certain requirements and restrictions. In December 2013, the FIO released a report entitled "How To Modernize And Improve The System Of Insurance Regulation In The United States." The report was required by the Dodd-Frank Act, and included 18 recommended areas of near-term reform for the states, including addressing capital adequacy and safety/soundness issues, reform of insurer resolution practices, and reform of marketplace regulation. The report also listed nine recommended areas for direct federal involvement in insurance regulation. Some of the recommendations outlined in the FIO report released in December 2013 have been implemented. The National Association of Registered Agents and Brokers Reform Act, signed into law in January 2015, simplifies the agent and broker licensing process across state lines. The FIO has also engaged with the supervisory colleges to monitor financial stability and identify regulatory gaps for large national and internationally active insurers.

The presidential administration in the United States and Congress have stated proposals to reform or repeal certain provisions of the Dodd-Frank Act, some of which have been implemented. Several proposals have been introduced, including proposals to limit or repeal the Financial Stability Oversight Council's (the Council) ability to designate nonbank financial companies as Systemically Important Financial Institutions (SIFI), eliminate the FIO, and increase Congressional oversight of the regulation issuing process. The Company cannot predict with any degree of certainty what impact, if any, such proposals will have on Aflac's business, financial condition, or results of operations.

Further Information

For further information concerning Aflac U.S. operations, regulation, change of control and dividend restrictions, see the Aflac U.S. Segment subsection of MD&A and Notes 2 and 13 of the Notes to the Consolidated Financial Statements in this report.

Other Operations

The Company's other operations include the Parent Company, results of reinsurance retrocession activities, and a printing subsidiary. For additional information on the Company's other operations, see the Other Operations subsection of MD&A and Note 8 in the Notes to the Consolidated Financial Statements.

Employees

As of December 31, 2017, Aflac Japan had 6,081 employees, Aflac U.S. had 4,864 employees, and the Company's other operations had 373 employees.

Executive Officers of the Registrant

NAME	PRINCIPAL OCCUPATION(1)	AGE
Daniel P. Amos	Chairman, Aflac Incorporated and Aflac, since 2001; Chief Executive Officer, Aflac Incorporated and Aflac, since 1990	66
Koji Ariyoshi	Executive Vice President, Director of Sales and Marketing, Aflac Japan, since 2012	64
Max K. Broden	Senior Vice President and Treasurer, Aflac Incorporated, since 2017; Senior Portfolio Manager, Norges Bank, from 2007 until 2017	39
Frederick J. Crawford	Executive Vice President, Chief Financial Officer, Aflac Incorporated, since 2015; Executive Vice President, Chief Financial Officer, CNO Financial Group from 2012 until 2015; Executive Vice President, Head of Investment and Corporate Development, Lincoln Financial Group from 2010 until 2012	54
J. Todd Daniels	Executive Vice President, Chief Actuary, Aflac Incorporated, since 2016; Global Chief Risk Officer, Aflac Incorporated, since 2016; Senior Vice President, Chief Actuary, Aflac, from 2015 until 2016; Global Chief Risk Officer, Aflac, from 2014 until 2016; Senior Vice President, Deputy Corporate Actuary, Aflac, from 2012 until 2014; Vice President, Financial Planning and Analysis, Aflac, from 2011 until 2012	47
June Howard	Chief Accounting Officer, Aflac Incorporated and Aflac, since 2010; Senior Vice President, Financial Services, Aflac Incorporated and Aflac, since 2010; Treasurer, Aflac, from 2011 until 2015	51
Eric M. Kirsch	Executive Vice President, Global Chief Investment Officer, Aflac, since 2012; President, Aflac Asset Management LLC, since 2017; First Senior Vice President, Global Chief Investment Officer, Aflac, from 2011 until 2012	57
Masatoshi Koide	President and Chief Operating Officer, Aflac Japan since 2017; Deputy President, Aflac Japan from 2016 until 2017; Executive Vice President, Aflac Japan from 2015 until 2016; First Senior Vice President, Aflac Japan from 2013 until 2015; Senior Vice President, Aflac Japan from 2012 until 2013	57
Charles D. Lake II	President, Aflac International, since 2014; Chairman, Aflac Japan, since 2008	56
Albert A. Riggieri	Senior Vice President, Corporate Actuary, Aflac, since 2016; Group Chief Actuary, Unum Group, until 2016	62
Audrey B. Tillman	Executive Vice President, General Counsel, Aflac Incorporated and Aflac, since 2014; Executive Vice President, Corporate Services, Aflac Incorporated, from 2008 until 2014	53
Teresa L. White	President, Aflac U.S., since 2014; Executive Vice President, Chief Operating Officer, Aflac, from 2013 until 2014; Executive Vice President, Chief Service Officer, Aflac, from 2012 until 2013; Executive Vice President, Chief Administrative Officer, Aflac, from 2008 until 2013	51

(1)Unless specifically noted, the respective executive officer has held the occupation(s) set forth in the table for at least the last five years. Each executive officer is appointed annually by the board of directors and serves until his or her successor is chosen and qualified, or until his or her death, resignation or removal.