SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)

12 Months Ended

Dec. 31, 2011

Description of Business

Description of Business

Aflac Incorporated (the Parent Company) and its subsidiaries (collectively, the Company) primarily sell supplemental health and life insurance in the United States and Japan. The Company’s insurance business is marketed and administered through 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. Additionally, Aflac U.S. markets and administers group products through Continental American Insurance Company (CAIC), branded as Aflac Group Insurance. Our insurance operations in the United States and our branch in Japan service the two markets for our insurance business. Aflac Japan’s revenues, including realized gains and losses on its investment portfolio, accounted for 75% of the Company’s total revenues in 2011 and 2010, compared with 73% in 2009. The percentage of the Company’s total assets attributable to Aflac Japan was 87% at December 31, 2011, and 86% at December 31, 2010.

Basis of Presentation

Basis of Presentation

We prepare our financial statements in accordance with U.S. generally accepted accounting principles (GAAP). These principles are established primarily by the Financial Accounting Standards Board (FASB). In these Notes to the Consolidated Financial Statements, references to GAAP issued by the FASB are derived from the FASB Accounting Standards Codification^TM (ASC). The preparation of financial statements in conformity with GAAP requires us to make estimates when recording transactions resulting from business operations based on currently available information. The most significant items on our balance sheet that involve a greater degree of accounting estimates and actuarial determinations subject to changes in the future are the valuation of investments, deferred policy acquisition costs, liabilities for future policy benefits and unpaid policy claims, and income taxes. These accounting estimates and actuarial determinations are sensitive to market conditions, investment yields, mortality, morbidity, commission and other acquisition expenses, and terminations by policyholders. As additional information becomes available, or actual amounts are determinable, the recorded estimates will be revised and reflected in operating results. Although some variability is inherent in these estimates, we believe the amounts provided are adequate.

The consolidated financial statements include the accounts of the Parent Company, its subsidiaries and those entities required to be consolidated under applicable accounting standards. All material intercompany accounts and transactions have been eliminated.

Translation of Foreign Currencies

Significant Accounting Policies

Translation of Foreign Currencies: The functional currency of Aflac Japan’s insurance operations is the Japanese yen. We translate our yen-denominated financial statement accounts into U.S. dollars as follows. Assets and liabilities are translated at end-of-period exchange rates. Realized gains and losses on security transactions are translated at the exchange rate on the trade date of each transaction. Other revenues, expenses and cash flows are translated using average exchange rates for the period. The resulting currency translation adjustments are reported in accumulated other comprehensive income. We include in earnings the realized currency exchange gains and losses resulting from transactions.

Aflac Japan maintains an investment portfolio of dollar-denominated securities on behalf of Aflac U.S., which serves as an economic currency hedge of a portion of our investment in Aflac Japan. The functional currency for these investments is the U.S. dollar. The related investment income and realized/unrealized investment gains and losses are also denominated in U.S. dollars. Since the functional currency of this portfolio is the U.S. dollar, there is no translation adjustment to record in other comprehensive income for these investments when the yen/dollar exchange rate changes. However, the foreign exchange gains and losses related to this portfolio are taxable in Japan and the U.S. when the securities mature or are sold. Until maturity or sale, deferred tax expense or benefit associated with the foreign exchange gains or losses is recognized in income tax expense on other comprehensive income.

We have designated a majority of the yen-denominated Uridashi and Samurai notes and yen-denominated loans issued by the Parent Company as a hedge of our investment in Aflac Japan. Outstanding principal and related accrued interest on these items are translated into U.S. dollars at end-of-period exchange rates. Currency translation adjustments are recorded through other comprehensive income and are included in accumulated other comprehensive income.

Insurance Revenue and Expense Recognition

Insurance Revenue and Expense Recognition: The supplemental health and life insurance policies we issue are classified as long-duration contracts. The contract provisions generally cannot be changed or canceled during the contract period; however, we may adjust premiums for supplemental health policies issued in the United States within prescribed guidelines and with the approval of state insurance regulatory authorities.

Insurance premiums for health and life policies are recognized ratably as earned income over the premium payment periods of the policies. When revenues are reported, the related amounts of benefits and expenses are charged against such revenues, so that profits are recognized in proportion to premium revenues during the period the policies are expected to remain in force. This association is accomplished by means of annual additions to the liability for future policy benefits and the deferral and subsequent amortization of policy acquisition costs.

The calculation of deferred policy acquisition costs and the liability for future policy benefits requires the use of estimates based on sound actuarial valuation techniques. For new policy issues, we review our actuarial assumptions and deferrable acquisition costs each year and revise them when necessary to more closely reflect recent experience and studies of actual acquisition costs. For policies in force, we evaluate deferred policy acquisition costs by major product groupings to determine that they are recoverable from future revenues. Any resulting adjustment is charged against net earnings.

Advertising expense is reported as incurred in insurance expenses in the consolidated statements of earnings.

Cash and Cash Equivalents

Cash and Cash Equivalents: Cash and cash equivalents include cash on hand, money market instruments and other debt instruments with a maturity of 90 days or less when purchased.

Investments

Investments: Our debt securities consist of fixed-maturity securities, which are classified as either held to maturity or available for sale. Securities classified as held to maturity are securities that we have the ability and intent to hold to maturity or redemption and are carried at amortized cost. All other fixed-maturity debt securities, our perpetual securities and our equity securities are classified as available for sale and are carried at fair value. If the fair value is higher than the amortized cost for debt and perpetual securities, or the purchase cost for equity securities, the excess is an unrealized gain, and if lower than cost, the difference is an unrealized loss.

The net unrealized gains and losses on securities available for sale, plus the unamortized unrealized gains and losses on debt securities transferred to the held-to-maturity portfolio, less related deferred income taxes, are recorded through other comprehensive income and included in accumulated other comprehensive income.

Amortized cost of debt and perpetual securities is based on our purchase price adjusted for accrual of discount, or amortization of premium, and recognition of impairment charges, if any. The amortized cost of debt and perpetual securities we purchase at a discount or premium will equal the face or par value at maturity or the call date, if applicable. Interest is reported as income when earned and is adjusted for amortization of any premium or discount.

We have investments in variable interest entities (VIEs). In periods prior to 2010, qualified special purpose entities (QSPEs), a type of VIE, were exempt from consolidation; however, other VIEs were evaluated for consolidation based on the variable interest created by the VIE. Our investments in VIEs and QSPEs were accounted for as fixed-maturity or perpetual securities. The majority of our investments in VIEs and QSPEs were held in our available-for-sale portfolio.

Subsequent to the adoption of updated accounting guidance on VIEs and QSPEs on January 1, 2010, our accounting treatment for these investments changed. The concept of QSPEs and their exemption from consolidation was eliminated, therefore, the former QSPEs are now VIEs which are evaluated for consolidation. We adopted the new criteria for evaluating VIEs for consolidation, which, instead of focusing on a quantitative approach, focuses on identifying which enterprise has the power to direct the activities of a variable interest entity that most significantly impact the entity’s economic performance and (1) the obligation to absorb losses of the entity or (2) the right to receive benefits from the entity. As a result of the application of this new guidance, we are the primary beneficiary of certain VIEs. While the VIEs generally operate within a defined set of documents, there are certain powers that are retained by us that are considered significant in our conclusion that we are the primary beneficiary. These powers vary by structure but generally include the initial selection of the underlying collateral or, for collateralized debt obligations (CDOs), the reference credits to include in the structure; the ability to obtain the underlying collateral in the event of default; and the ability to appoint or dismiss key parties in the structure. In particular, our powers surrounding the underlying collateral were the most significant powers since those most significantly impact the economics of the VIE. We have no obligation to provide any continuing financial support to any of the entities in which we are the primary beneficiary. Our maximum loss is limited to our original investment. Neither we nor any of our creditors have the ability to obtain the underlying collateral. Nor do we have control over the instruments in the VIEs, unless there is an event of default. This collateral is reported separately under the captions fixed maturities- and perpetual securities- consolidated variable interest entities on our balance sheet.

For those entities where we are the primary beneficiary, the assets consolidated are fixed-maturity securities, perpetual securities and derivative instruments. The calculation method of the yields on these investments did not change as a result of adoption of the new accounting guidance.

For the collateralized mortgage obligations (CMOs) held in our fixed-maturity securities portfolio, we recognize income using a constant effective yield, which is based on anticipated prepayments and the estimated economic life of the securities. When estimates of prepayments change, the effective yield is recalculated to reflect actual payments to date and anticipated future payments. The net investment in CMO securities is adjusted to the amount that would have existed had the new effective yield been applied at the time of acquisition. This adjustment is reflected in net investment income.

We use the specific identification method to determine the gain or loss from securities transactions and report the realized gain or loss in the consolidated statements of earnings. Securities transactions are accounted for based on values as of the trade date of the transaction.

The majority of our investments are evaluated for other-than-temporary impairment using our debt impairment model. Our debt impairment model focuses on the ultimate collection of the cash flows from our investments. Our credit analysts/research personnel routinely monitor and evaluate the difference between the amortized cost and fair value of our investments. Additionally, credit analysis and/or credit rating issues related to specific investments may trigger more intensive monitoring to determine if a decline in fair value is other than temporary. For investments with a fair value below amortized cost, the determination of whether the impairment is other than temporary is subjective and involves the consideration of various factors and circumstances, which includes but is not limited to the following:

• issuer financial condition, including profitability and cash flows

• credit status of the issuer

• the issuer’s specific and general competitive environment

• published reports

• general economic environment

• future prospects of the issuer

• regulatory, legislative and political environment

• the severity of the decline in fair value

• the length of time the fair value is below cost

• other factors as may become available from time to time

• our intent or need to dispose of the security prior to recovery of its fair value to amortized cost

This process is not exact and requires consideration of risks such as credit risk, which to a certain extent can be controlled, and interest rate risk, which cannot be controlled. Therefore, if an investment’s amortized cost exceeds its fair value solely due to changes in interest rates, impairment may not be appropriate.

If, after monitoring and analyses, management believes that fair value will not recover to amortized cost prior to the disposal of the security, we recognize an other-than-temporary impairment of the security. Once a security is considered to be other-than-temporarily impaired, the impairment loss is separated into two separate components: the portion of the impairment related to credit and the portion of the impairment related to factors other than credit. We automatically recognize a charge to earnings for the credit-related portion of other-than-temporary impairments. Impairments related to factors other than credit are charged to earnings in the event we intend to sell the security prior to the recovery of its amortized cost or if it is more likely than not that we would be required to dispose of the security prior to recovery of its amortized cost; otherwise, non-credit-related other-than-temporary impairments are charged to other comprehensive income.

Our investments in perpetual securities that are rated below investment grade are evaluated for other-than-temporary impairment under our equity impairment model. Our equity impairment model focuses on the severity of a security’s decline in fair value coupled with the length of time the fair value of the security has been below amortized cost and the financial condition and near-term prospects of the issuer.

We lend fixed-maturity securities to financial institutions in short-term security lending transactions. These securities continue to be carried as investment assets on our balance sheet during the terms of the loans and are not reported as sales. We receive cash or other securities as collateral for such loans. For loans involving unrestricted cash collateral, the collateral is reported as an asset with a corresponding liability for the return of the collateral. For loans collateralized by securities, the collateral is not reported as an asset or liability.

For further information regarding our investments, see Note 3.

Derivatives and Hedging

Derivatives and Hedging: We do not use derivatives for trading purposes, nor do we engage in leveraged derivative transactions.

Freestanding derivative instruments are reported in the consolidated balance sheet at fair value and are reported in other assets and other liabilities, with changes in value reported in earnings and/or other comprehensive income. These freestanding derivatives are interest rate swaps, credit default swaps (CDSs) and/or foreign currency swaps. Interest rate and foreign currency swaps are used within VIEs to hedge the risk arising from interest rate and currency exchange risk, while the CDSs are used to increase the yield and improve the diversification of the portfolio. Interest rate swaps are used to hedge the variability of interest cash flows associated with our variable rate notes.

From time to time, we purchase certain investments that contain an embedded derivative. We assess whether this embedded derivative is clearly and closely related to the asset that serves as its host contract. If we deem that the embedded derivative’s terms are not clearly and closely related to the host contract, and a separate instrument with the same terms would qualify as a derivative instrument, the derivative is separated from that contract, held at fair value and reported with the host instrument in the consolidated balance sheet, with changes in fair value reported in earnings. If we have elected the fair value option, the embedded derivative is not bifurcated, and the entire investment is held at fair value with changes in fair value reported in earnings.

For those relationships where we seek hedge accounting, we formally document all relationships between hedging instruments and hedged items, as well as our risk-management objectives and strategies for undertaking various hedge transactions. This process includes linking derivatives and nonderivatives that are designated as hedges to specific assets or liabilities on the balance sheet. We also assess, both at inception and on an ongoing basis, whether the derivatives and nonderivatives used in hedging activities are highly effective in offsetting changes in fair values or cash flows of the hedged items. The assessment of hedge effectiveness determines the accounting treatment of noncash changes in fair value.

Changes in the fair value of any of our derivatives that are designated and qualify as cash flow hedges are recorded in other comprehensive income as long as they are deemed effective. Any hedge ineffectiveness is recorded immediately in current period earnings as a realized investment gain or loss. Periodic derivative net coupon settlements are recorded in the line item of the consolidated statements of earnings in which the cash flows of the hedged item are recorded. Derivatives that are not designated as hedges are carried at fair value with all changes in fair value recorded as a realized investment gain or loss. We include the fair value of all freestanding derivatives in either other assets or other liabilities on the balance sheet.

We have designated the majority of our yen-denominated Samurai and Uridashi notes and yen-denominated loans (see Note 8) as nonderivative hedges of the foreign currency exposure to our investment in Aflac Japan. At the beginning of each quarter, we make our net investment hedge designation. If the total of our designated yen-denominated liabilities is equal to or less than our net investment in Aflac Japan, the hedge is deemed to be effective and the related exchange effect is reported in the unrealized foreign currency component of other comprehensive income. Should these designated yen-denominated liabilities exceed our investment in Aflac Japan, the foreign exchange effect on the portion of the liabilities that exceeds our investment in Aflac Japan would be recognized in net earnings (other income).

For further information regarding derivatives and hedging, see Note 4.

Deferred Policy Acquisition Costs

Deferred Policy Acquisition Costs: The costs of acquiring new business are deferred and amortized with interest over the premium payment periods in proportion to the ratio of annual premium income to total anticipated premium income. Anticipated premium income is estimated by using the same mortality, persistency and interest assumptions used in computing liabilities for future policy benefits. In this manner, the related acquisition expenses are matched with revenues. Deferred costs include the excess of current-year commissions over ultimate renewal-year commissions and certain incremental direct and allocated policy issue, underwriting and marketing expenses. All of these costs vary with and are primarily related to the production of new business.

For some products, policyholders can elect to modify product benefits, features, rights or coverages by exchanging a contract for a new contract or by amendment, endorsement, or rider to a contract, or by the election of a feature or coverage within a contract. These transactions are known as internal replacements. For internal replacement transactions where the resulting contract is substantially unchanged, the policy is accounted for as a continuation of the replaced contract. Unamortized deferred acquisition costs from the original policy continue to be amortized over the expected life of the new policy, and the costs of replacing the policy are accounted for as policy maintenance costs and expensed as incurred. Internal replacement transactions that result in a policy that is not substantially unchanged are accounted for as an extinguishment of the original policy and the issuance of a new policy. Unamortized deferred acquisition costs on the original policy that was replaced are immediately expensed, and the costs of acquiring the new policy are capitalized and amortized in accordance with our accounting policies for deferred acquisition costs.

See the New Accounting Pronouncements section of Note 1 for a discussion on accounting guidance that will change our accounting policy for deferred acquisition costs effective January 1, 2012.

Policy Liabilities - Future Policy Benefits

Policy Liabilities: Future policy benefits represent claims that are expected to occur in the future and are computed by a net level premium method using estimated future investment yields, persistency and recognized morbidity and mortality tables modified to reflect our experience, including a provision for adverse deviation. These assumptions are generally established at the time a policy is issued.

Policy Liabilities - Unpaid Policy Claims

Unpaid policy claims are estimates computed on an undiscounted basis using statistical analyses of historical claims experience adjusted for current trends and changed conditions. The ultimate liability may vary significantly from such estimates. We regularly adjust these estimates as new claims experience emerges and reflect the changes in operating results in the year such adjustments are made.

For internal replacements that are determined to not be substantially unchanged, policy liabilities related to the original policy that was replaced are immediately released, and policy liabilities are established for the new insurance contract.

Income Taxes

Income Taxes: Income tax provisions are generally based on pretax earnings reported for financial statement purposes, which differ from those amounts used in preparing our income tax returns. Deferred income taxes are recognized for temporary differences between the financial reporting basis and income tax basis of assets and liabilities, based on enacted tax laws and statutory tax rates applicable to the periods in which we expect the temporary differences to reverse. We record deferred tax assets for tax positions taken based on our assessment of whether the tax position is more likely than not to be sustained upon examination by taxing authorities. A valuation allowance is established for deferred tax assets when it is more likely than not that an amount will not be realized.

As discussed in the Translation of Foreign Currencies section above, Aflac Japan maintains a dollar-denominated investment portfolio on behalf of Aflac U.S. While there are no translation effects to record in other comprehensive income, the deferred tax expense or benefit associated with foreign exchange gains or losses on the portfolio is recognized in other comprehensive income until the securities mature or are sold. Total income tax expense (benefit) related to items of other comprehensive income (loss) included a deferred tax benefit of $152 million in 2011, compared with a deferred tax benefit of $322 million in 2010 and a deferred tax expense of $12 million in 2009 for this dollar-denominated portfolio. Excluding these amounts from total taxes on other comprehensive income would result in an effective income tax rate on pretax other comprehensive income (loss) of 34% in 2011, 31% in 2010, and 35% in 2009.

Policyholder Protection Corporation and State Guaranty Association Assessments

Policyholder Protection Corporation and State Guaranty Association Assessments: In Japan, the government has required the insurance industry to contribute to a policyholder protection corporation. We recognize a charge for our estimated share of the industry’s obligation once it is determinable. We review the estimated liability for policyholder protection corporation contributions on an annual basis and report any adjustments in Aflac Japan’s expenses.

In the United States, each state has a guaranty association that supports insolvent insurers operating in those states. To date, our state guaranty association assessments have not been material.

Treasury Stock

Treasury Stock: Treasury stock is reflected as a reduction of shareholders’ equity at cost. We use the weighted-average purchase cost to determine the cost of treasury stock that is reissued. We include any gains and losses in additional paid-in capital when treasury stock is reissued.

Share-Based Compensation

Share-Based Compensation: We measure compensation cost related to our share-based payment transactions at fair value on the grant date, and we recognize those costs in the financial statements over the vesting period during which the employee provides service in exchange for the award.

Earnings Per Share

Earnings Per Share: We compute basic earnings per share (EPS) by dividing net earnings by the weighted-average number of unrestricted shares outstanding for the period. Diluted EPS is computed by dividing net earnings by the weighted-average number of shares outstanding for the period plus the shares representing the dilutive effect of share-based awards.

Recently Adopted Accounting Pronouncements

New Accounting Pronouncements

Recently Adopted Accounting Pronouncements

Fair value measurements and disclosures: In January 2010, the FASB issued amended accounting guidance on fair value disclosures. This guidance requires the activity in fair value hierarchy Level 3 for purchases, sales, issuances, and settlements to be reported on a gross, rather than net, basis. We adopted this guidance as of January 1, 2011. The adoption did not have an impact on our financial position or results of operations.

Accounting for variable interest entities and transfers of financial assets: In June 2009, the FASB issued amended guidance on accounting for VIEs and transfers of financial assets. This guidance defines new criteria for determining the primary beneficiary of a VIE; increases the frequency of required reassessments to determine whether a company is the primary beneficiary of a VIE; eliminates the exemption for the consolidation of QSPEs; establishes conditions for reporting a transfer of a portion of a financial asset as a sale; modifies the financial asset derecognition criteria; and requires additional disclosures. We adopted the provisions of this guidance on January 1, 2010 as a cumulative effect of change in accounting principle. We were required to consolidate certain of the VIEs with which we are currently involved. We were not required to deconsolidate any VIEs on January 1, 2010.

Upon the initial consolidation of the VIEs on January 1, 2010, the assets, liabilities, and noncontrolling interests of the VIEs were recorded at their carrying values, which is the amounts at which the assets, liabilities, and noncontrolling interests would have been carried in the consolidated financial statements when we first met the conditions to be the primary beneficiary. For any of the VIEs that were required to be consolidated, we also considered whether any of the derivatives in these structures qualified on January 1, 2010, as a cash flow hedge of the changes in cash flows attributable to foreign currency and/or interest rate risk. Certain of the swaps did not qualify for hedge accounting since the swap had a fair value on January 1, 2010. Other swaps did not qualify for hedge accounting since they increased, rather than reduced, cash flow risk.

For additional information concerning our investments in VIEs and derivatives, see Notes 3 and 4, respectively.

Accounting Pronouncements Pending Adoption

Accounting Pronouncements Pending Adoption

Presentation of comprehensive income: In June 2011, the FASB issued guidance to amend the presentation of comprehensive income. The amendment requires that all non-owner changes in stockholders’ equity be presented either in a single continuous statement of comprehensive income or in two separate but consecutive statements. This guidance is effective for interim and annual periods beginning after December 15, 2011. The amendment also requires reclassification adjustments for items that are reclassified from other comprehensive income to net income to be presented in the statements where the components of net income and the components of other comprehensive income are presented; however, in December 2011, the FASB temporarily deferred the effective date of this additional requirement. The adoption of this guidance will not have an impact on our financial position or results of operations.

Fair value measurements and disclosures: In May 2011, the FASB issued guidance to amend the fair value measurement and disclosure requirements. Most of the amendments are clarifications of the FASB’s intent about the application of existing fair value measurement and disclosure requirements. Other amendments change a particular principle or requirement for measuring fair value or disclosing information about fair value measurements. The new fair value measurement disclosures include additional quantitative and qualitative disclosures for Level 3 measurements, including a qualitative sensitivity analysis of fair value to changes in unobservable inputs, and categorization by fair value hierarchy level for items for which the fair value is only disclosed. This guidance is effective for interim and annual periods beginning after December 15, 2011. We expect that the adoption of this guidance will impact our financial statement disclosures, but it will not affect our financial position or results of operations.

Accounting for costs associated with acquiring or renewing insurance contracts: In October 2010, the FASB issued amended accounting guidance on accounting for costs associated with acquiring or renewing insurance contracts. Only incremental direct costs associated with the successful acquisition of a new or renewal contract may be capitalized. The amendment also prohibits capitalizing direct-response advertising costs unless they meet certain criteria. This guidance is effective on a prospective or retrospective basis for interim and annual periods beginning after December 15, 2011. We estimate that the retrospective adoption of this accounting standard effective January 1, 2012, will result in an after-tax cumulative reduction to opening retained earnings of $400 to $500 million, or 3.6% to 4.5% of shareholder’s equity, as of December 31, 2010. Furthermore, the adoption of this accounting standard will result in an immaterial impact on net income in 2011 and 2012 and for all preceding years impacted by the retrospective adoption.

Recent accounting guidance not discussed above is not applicable or did not have an impact to our business.