{"url_path":"/sec/mfg/10-k/2026/cover-page","section_key":"cover-page","section_title":"Cover Page","topic":"sec","document":{"doc_type":"20-F","doc_date":"2026-06-26","source_url":"https://www.sec.gov/Archives/edgar/data/1335730/0001193125-26-283791-index.html","accession_number":"0001193125-26-283791","cik":"0001335730","ticker":"MFG","issuer_name":"MIZUHO FINANCIAL GROUP INC","edgar_url":"https://www.sec.gov/Archives/edgar/data/1335730/0001193125-26-283791-index.html","primary_entity_key":"0001335730","primary_entity_name":"MIZUHO FINANCIAL GROUP INC"},"word_count":11529,"has_tables":true,"body_markdown":"ANNUAL REPORT\n\nfalseFY0001335730Others includes primarily foreign exchange translation.The majority of total foreign consist of corporate.These amounts are revenues from contracts within the scope of ASC 606, “Revenue from contracts with customers” (“ASC 606”).These amounts are revenues from contracts that do not meet the scope of ASC 606.Part of these amounts are considered to be revenues from contracts that are within the scope of ASC 606.Most of the lending-related fees such as commitment fees and arrangement fees are not within the scope of ASC 606.Agency mortgage-backed securities presented in this line consist of Japanese agency mortgage-backed securities, of which the fair values were ¥308,626 million at March 31, 2025, and ¥281,815 million at March 31, 2026. All Japanese agency mortgage-backed securities are issued by Japan Housing Finance Agency, a Japanese government-sponsored enterprise.The MHFG Group included assets of ¥68,966 million and liabilities of ¥131,210 million, which are mainly financial assets and financial liabilities, relating to a transferred business and classified as held for sale in Other at March 31, 2025.This represents the maximum amount the Group could possibly be required to record in its consolidated statements of income associated with on-balance-sheet exposures and off-balance-sheet liabilities such as undrawn commitments.Charge-offs increased by ¥224,941 million from the fiscal year ended March 31, 2025 to ¥272,985 million for the fiscal year ended March 31, 2026 due mainly to a downgrade in obligor rating at a domestic corporate borrower.The required ratios disclosed above, at March 31, 2025 and 2026, include the capital conservation buffer of 2.5%, the countercyclical capital buffer of 0.11% and 0.13%, respectively, and the additional loss absorbency requirements for G-SIBs and D-SIBs of 1.0%, which are all in addition to the regulatory minima. The respective required amounts are determined by applying the ratios to the sum of the risk weighted assets and certain other risk amounts.Derivative receivables and payables are recorded in Trading account assets and Trading account liabilities, respectively.In accordance with ASC 820, certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented for these classes of assets are intended to permit the reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position. The amounts of unfunded commitments related to these investments at March 31, 2025 and 2026 were ¥58 billion and ¥190 billion, respectively.Trading securities include foreign currency denominated securities for which the MHFG Group elected the fair value option.The amount includes CLO and convertible bonds, which are classified in Level 3.The financial statement line item in which the amounts in the before tax column are reported in the consolidated statements of income is listed to the right of the table.The financial statement line items in which the amounts in the tax effect and the net of tax attributable to noncontrolling interest columns are reported in the consolidated statements of income are Income tax expense (benefit) and Net income (loss), respectively.The primary component of the retail portfolio segment is housing loans to individuals which obligor category is classified based on past due status. The trigger to reclassify obligors from normal obligors to watch obligors excluding special attention obligors is when the past due status is more than 30 days.Corporate of foreign included ¥166 billion and ¥169 billion of lease receivables that were receivables arising from direct financing leasing at March 31, 2025 and 2026, respectively.Corporate of foreign included ¥166 billion and ¥169 billion of lease receivables that were receivables arising from direct financing leasing at March 31, 2025 and 2026, respectively.On March 31, 2025, the National Diet of Japan approved a bill affecting the effective statutory tax rates of MHFG and its domestic subsidiaries. As a result, the effective statutory tax rate will be increased to 31.52% from the previous rate of 30.62% beginning on or after the fiscal year ending March 31, 2027. The increase in the Group’s balance of net deferred tax assets, reflecting such tax rate increases, was recognized as a reduction to Income tax expense in the fiscal year ended March 31, 2025.Commitments to lend to borrowers experiencing financial difficulty that were granted modifications were immaterial at March 31, 2025 and 2026.The allowance for credit losses on loans is based on macroeconomic-sensitive models that rely on historical performance and macroeconomic scenarios to forecast expected credit losses. Modifications of loans impact expected credit losses by affecting the likelihood of default.The financial effects of loan modifications, which were largely in the form of term extensions and interest rate reductions, included extending the weighted-average life of the loans by 11.0 months and 20.2 months, and reducing the weighted-average contractual interest rate by 0.5% and 1.0% for the fiscal years ended March 31, 2025 and 2026, respectively.The amount includes ¥82,572 million and ¥59,644 million related to MHBK’s foreign tax credit carryforwards as of March 31, 2025 and 2026, respectively. The amount is mainly offset by valuation allowance, and if not utilized, the amount will expire during the fiscal year ending March 31, 2027.Income taxes applicable to us in Japan are imposed by the national and local governments, and the aggregate of these taxes resulted in a combined normal effective statutory tax rate of 30.62% for each of the fiscal years ended March 31, 2024 and 2025. MHFG used the Japanese statutory corporate income tax rate of 25.59% as the applicable national statutory tax rate in the reconciliation of the statutory tax rate to the effective tax rate for the fiscal year ended March 31, 2026. Foreign subsidiaries are subject to income taxes of the jurisdictions in which they operate, and these taxes are reflected in the effective income tax rate.Local taxes in Tokyo made up the majority (greater than 50%) of the tax effect in this category.The amounts that have been reclassified out of Accumulated other comprehensive income (loss), net of tax into net income are presented in Note 16 “Accumulated other comprehensive income (loss), net of tax.”Agency mortgage-backed securities presented in this line consist of Japanese and Foreign agency mortgage-backed securities, of which the fair values were ¥315,536 million and ¥22 million, respectively, at March 31, 2025, and ¥281,815 million and ¥21 million, respectively, at March 31, 2026. All Japanese agency mortgage-backed securities are issued by Japan Housing Finance Agency, a Japanese government-sponsored enterprise. Foreign agency mortgage-backed securities primarily consist of Government National Mortgage Association (“Ginnie Mae”) securities, which are guaranteed by the United States government.Other debt securities presented in this line primarily consist of Foreign negotiable certificates of deposit (“NCDs”) and asset-backed securities (“ABS”), of which the total fair values were ¥221,706 million at March 31, 2025, and ¥287,547 million at March 31, 2026.Accrued interest receivables of ¥20,845 million at March 31, 2025, and ¥29,997 million at March 31, 2026 are excluded from amortized cost and included in Accrued income.Amortized cost, net of the allowance for credit losses, of which the amounts related to available-for-sale securities were ¥nil at both March 31, 2025 and 2026.All Agency mortgage-backed securities presented in this line are Ginnie Mae securities.Amounts relating to master netting arrangements or similar agreements where the MHFG Group does not have the legal right of set-off or where uncertainty exists as to the enforceability of these agreements are excluded. For derivatives, the table includes amounts relating to over-the-counter (“OTC”) and OTC-cleared derivatives that are subject to enforceable master netting arrangements or similar agreements.Derivative assets and liabilities are recorded in Trading account assets and Trading account liabilities, respectively.The amounts of Receivables under resale agreements and Payables under repurchase agreements subject to enforceable industry standard master repurchase agreements with netting terms were ¥26,995 billion and ¥37,646 billion, respectively, at March 31, 2025, and ¥29,092 billion and ¥36,715 billion, respectively, at March 31, 2026.For derivatives, amounts include derivative assets or liabilities and securities collateral that are eligible for offsetting under enforceable master netting arrangements or similar agreements.Amounts do not exceed the net amounts presented on the balance sheet and do not include the effect of overcollateralization, where it exists.The amounts of Receivables under securities borrowing transactions and Payables under securities lending transactions subject to enforceable industry standard master lending agreements with netting terms were ¥2,078 billion and ¥1,602 billion, respectively, at March 31, 2025, and ¥1,761 billion and ¥1,968 billion, respectively, at March 31, 2026.The amounts of derivative assets and liabilities subject to enforceable master netting arrangements or similar agreements were ¥15,324 billion and ¥15,722 billion, respectively, at March 31, 2025, and ¥23,448 billion and ¥23,745 billion, respectively, at March 31, 2026.Averages are calculated by weighting each input by the relative fair value of the respective financial instruments except for derivative related inputs where medians are used.Total Level 3 derivative exposures have been netted on the table for presentation purposes only.Amounts represent total gains or losses recognized in earnings and other comprehensive income (loss) during the period. These gains or losses were attributable to the change in fair value relating to assets and liabilities classified as Level 3 that were still held at March 31, 2025 and 2026. The amounts of unrealized gains (losses) in other comprehensive income (loss) are related to Available-for-sale securities and Long-term debt, which were ¥(10) billion and ¥6 billion, respectively, at March 31, 2025, and ¥(6) billion and ¥(6) billion, respectively, at March 31, 2026.Customer relationships were mainly acquired in connection with the merger of MHSC and Shinko on May 7, 2009 and the integration among asset management companies on October 1, 2016. See Note 1 “Basis of presentation and summary of significant accounting policies” for further information.Amounts represent the outstanding balances of nonaccrual loans. The MHFG Group’s policy for placing loans in nonaccrual status is consistent with the Group’s definition of nonaccrual loans.Amounts represent the amount of interest income on nonaccrual loans recognized on a cash basis and included in Interest income on loans in the consolidated statements of income.The interest rates disclosed reflect the range of contractual rates in effect at March 31, 2026.Maturity information disclosed is the range of maturities at March 31, 2026.Income and expenses of foreign branches of MHBK and foreign subsidiaries with functional currencies other than Japanese Yen have been translated for purposes of segment reporting using the budgeted foreign currency rates. Prior period comparative amounts for such foreign currency income and expenses have been translated using current period budgeted foreign currency rates.The required ratios disclosed above, at March 31, 2025 and 2026, include a leverage ratio buffer required to be met at 50% of the additional loss absorbency requirements applied to the Group as a G-SIB under the finalized Basel III reforms. The required and actual amounts disclosed above at March 31, 2025 and 2026 exclude amounts of deposits to the Bank of Japan.The core capital ratio is a Japan-specific regulatory indicator that measures capital adequacy under the domestic standard applicable to banks with only domestic operations. Since transitioning to a domestic standard applicable to banks with only domestic operations from December 31, 2025, Mizuho Trust & Banking is subject to the domestic standard and is no longer subject to the leverage ratio requirements.For the fiscal year ended March 31, 2026, Goodwill acquired is mainly related to the acquisition of UPSIDER Holdings, Inc.Net business profits (losses) is used in Japan as a measure of the profitability of core banking operations, and is defined as gross profits (as defined above) less general and administrative expenses (excluding non-allocated gains (losses), net) plus equity in earnings (losses) of equity method investees—net less amortization of goodwill and others. Measurement of net business profits (losses) is required for regulatory reporting to the Financial Services Agency of Japan. “Others” includes the following items: • profits and expenses pertaining to consolidated subsidiaries that are not subject to allocation; • consolidating adjustments, including elimination of internal transaction between each segment; • equity in earnings (losses) of equity method investees—net that are not subject to allocation; and • profits and losses pertaining to derivative transactions that reflect the counterparty risk of the individual parties and other factors in determining fair market value.“General and administrative expenses” excludes non-allocated gains (losses), net, which primarily includes personnel expenses, depreciation expenses, and occupancy expenses. When the CODM assesses segment performance and decides how to allocate resources, these expenses are regularly provided to the CODM in an aggregated form as “General and administrative expenses” and may be used, for example, to evaluate the expense ratio against segment profits and to compare them with the budgeted expense information. Internal valuation model includes discounted cash flow models and the Black-Scholes option pricing model.Gains (losses) in Earnings are reported in Trading account gains (losses)—net, Foreign exchange gains (losses)—net or Other noninterest income (expenses).Gains (losses) in Earnings are reported in Investment gains (losses)—net.Gains (losses) in OCI are reported in Other comprehensive income (loss).Gains (losses) in Earnings are reported in Other noninterest income (expenses).These inputs are mainly used for determining the fair values of securitization products such as CDO, CLO and ABS, other than RMBS and CMBS.This input is mainly used for determining the fair values of Japanese corporate bonds.In June 2024, based on various approvals, MHFG and certain domestic subsidiaries communicated to their employees the amendment to the defined benefit plans that was effective as of July 1, 2024. In accordance with ASC 715, “Compensation—Retirement Benefits” (“ASC 715”), any change in projected benefit obligations due to a plan amendment is required to be recognized as prior service benefits (cost) as of the amendment date. Accordingly, the MHFG Group recognized ¥9,360 million of prior service benefits for the fiscal year ended March 31, 2025.“Fixed assets” is presented based on Japanese GAAP and corresponds to the total amount of the following U.S. GAAP accounts: Premises and equipment—net; Goodwill; Intangible assets; and right-of-use assets related to operating leases included in Other assets. The above table does not include other asset amounts because “Fixed assets” is the only balance sheet measure that the CODM uses when evaluating and making decisions pertaining to the operating segments. “Others” in “Fixed assets” includes assets of headquarters that have not been allocated to each segment, “Fixed assets” pertaining to consolidated subsidiaries that are not subject to allocation, consolidating adjustments and others. Certain “Fixed assets” expenses have been allocated to each segment using reasonable allocation criteria.Short-term notes are issued under the laws of Japan in the form of commercial paper.The amounts of commercial paper and short-term notes issued by MHFG’s subsidiaries were ¥2,138,133 million and ¥567,000 million, respectively, at March 31, 2025, and ¥1,921,799 million and ¥353,500 million, respectively, at March 31, 2026.In accordance with ASC 820, certain plan assets that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy.Total expenses are comprised of Interest expense, Provision (credit) for credit losses and Noninterest expenses. Amounts relate to transactions where the Group acts as lender in a securities lending agreement and receives securities that can be sold or pledged as collateral. In these transactions, the Group recognizes the securities received at fair value within Other assets and the obligation to return those securities as a liability within Other liabilities.Amounts represent items for which the Group elected the fair value option or for which it applied the practicability exception.The amount includes highly liquid government bonds classified as held for sale relating to a transferred business, which are classified in Level 1.Amounts include gains and losses on currency swaps.Amounts do not include the net gains (losses) of ¥(952) million, ¥(964) million and ¥0 million on the credit derivatives economically managing the credit risk of loans during the fiscal years ended March 31, 2024, 2025 and 2026, respectively. The net gains (losses) is recorded in Other noninterest income (expenses).Amounts include realized and unrealized gains and losses on both derivative instruments and nonderivative instruments. Amounts on derivative instruments include gains and losses on forward foreign exchange contracts and currency options. Amounts on nonderivative instruments include translation gains and losses related to foreign currency-denominated debt securities reported as Trading securities.Total revenue is comprised of Interest and dividend income and Noninterest income.    The United Kingdom net operating loss carryforwards may be carried forward indefinitely for tax purposes.¥25 billion of the Japan deferred tax assets of ¥56 billion is related to MHFG, which is fully offset by a valuation allowance, and will mostly expire during the fiscal year ending March 31, 2032. ¥16 billion of the Japan deferred tax assets of ¥56 billion is related to MHBK and will mostly expire during the fiscal year ending March 31, 2034.¥25 billion of the Japan deferred tax assets of ¥31 billion is related to MHFG, which is fully offset by a valuation allowance, and will mostly expire during the fiscal year ending March 31, 2032. ¥3 billion of the Japan deferred tax assets of ¥31 billion is related to MHBK and will mostly expire during the fiscal year ending March 31, 2034.Figures assume that the countercyclical capital buffer will continue to be 0.13% after March 2026.    Figures assume that the additional loss absorbency requirements applied to the Group as a G-SIB and D-SIB continue to be 1.0% on a fully effective basis in future years.For the fiscal year ended March 31, 2024, Goodwill acquired is entirely related to the acquisition of Greenhill & Co., Inc.The U.S. GAAP adjustments are primarily comprised of GAAP differences mainly from right-of-use assets related to operating leases not recognized under Japanese GAAP; internally developed software, which was impaired under Japanese GAAP; land, which was revalued under Japanese GAAP; and the consolidation of certain variable interest entities, which are not consolidated under Japanese GAAP.Goodwill is recorded at a designated reporting unit level for the purpose of assessing impairment. Goodwill is not allocated to the reportable segments in Note 30 “Business segment information.”The above table does not include securities-for-securities lending transactions of ¥125 billion at March 31, 2025 and ¥—  billion at March 31, 2026, where the MHFG Group acts as lender and receives securities that can be sold or pledged as collateral. In these transactions, the Group recognizes the securities received at fair value within Other assets and the obligation to return those securities as a liability within Other liabilities.“Gross profits + Net gains (losses) related to ETFs and others” is reported instead of sales reported by general corporations. Gross profits is defined as the sum of net interest income, fiduciary income, net fee and commission income, net trading income and net other operating income. Net gains (losses) related to ETFs and others consist of net gains (losses) on ETFs held by MHBK and MHTB on their non-consolidated basis and net gains (losses) on operating investment securities of MHSC on its consolidated basis. For the fiscal years ended March 31, 2024, 2025 and 2026, net gains (losses) related to ETFs and others amounted to ¥(31.0) billion, ¥45.2 billion and ¥38.3 billion, respectively, of which ¥(37.0) billion, ¥37.0 billion and ¥30.8 billion are included in GMC, respectively.Loans, net of allowance include items measured at fair value on a nonrecurring basis.“Gross profits + Net gains (losses) related to ETFs and others” is reported instead of sales reported by general corporations. Gross profits is defined as the sum of net interest income, fiduciary income, net fee and commission income, net trading income and net other operating income. Net gains (losses) related to ETFs and others consist of net gains (losses) on ETFs held by MHBK and MHTB on their non-consolidated basis and net gains (losses) on operating investment securities of MHSC on its consolidated basis. For the fiscal years ended March 31, 2024, 2025 and 2026, net gains (losses) related to ETFs and others amounted to ¥(31.0) billion, ¥45.2 billion and ¥0.0 billion, respectively, of which ¥(37.0) billion, ¥37.0 billion and ¥0.0 billion are included in GMC, respectively.Notional amount includes the sum of gross long and gross short third-party contracts.These amounts include the net unrealized gains resulting from changes in fair values of structured notes that contain embedded derivatives. See Note 26 “Fair value” for further details.Amounts include the net gains (losses) of ¥(952) million, ¥(964) million and ¥(809) million on the credit derivatives economically managing the credit risk of loans during the fiscal years ended March 31, 2024, 2025 and 2026, respectively.The MHFG Group transferred certain loans from Loans held for sale to Loans at March 31, 2026, totaling ¥186,640 million.Net operating loss carryforwards related to Japanese local taxes at MHFG amounted to ¥518 billion (tax-effected ¥25 billion) as of March 31, 2026 and are not included in the table. The net operating loss carryforwards are fully offset by valuation allowance and will mostly expire during the fiscal year ending March 31, 2032.Net operating loss carryforwards related to Japanese local taxes at MHBK amounted to ¥80 billion (tax-effected ¥3 billion) as of March 31, 2026 and are not included in the table. The net operating loss carryforwards will mostly expire during the fiscal year ending March 31, 2034.Including the net operating loss carryforwards which may be carried forward indefinitely in the United Kingdom.This class represents equity securities held in the employee retirement benefit trusts of ¥758 billion and ¥672 billion carried at fair value at March 31, 2025 and 2026, respectively, which are well-diversified across industries.These classes primarily include pension investment fund trusts. Investments in these classes are generally measured at fair value and can be redeemed within a short-term period upon request.Investments in this class are measured at conversion value, which is equivalent to fair value.Amounts primarily include cash and short-term assets carried at fair value. The amount includes ¥24,943 million and ¥24,852 million related to MHFG’s net operating loss carryforwards resulting mainly from intercompany capital transactions in relation to the share buyback conducted by MHSC as of March 31, 2025 and 2026, respectively. The tax effect of the net operating loss carryforwards is fully offset by ¥24,943 million and ¥24,852 million, respectively, of valuation allowance as a result of considering all available evidence regarding sources of future taxable income including historical trends in taxable income in the preceding periods and forecasted taxable income.The amount includes ¥11,423 million and ¥1,613 million related to MHSC’s net operating loss carryforwards resulting mainly from the organizational restructuring of certain foreign subsidiaries as of March 31, 2025 and 2026, respectively. The tax effect of the net operating loss carryforwards as of March 31, 2025 is substantially offset by ¥4,408 million of valuation allowance as a result of considering all available evidence regarding sources of future taxable income including historical trends in taxable income in the preceding periods and forecasted taxable income.Proceeds from sales of Equity securities as well as Purchases of Equity securities include cash activity related to Other investments, the amounts of which are not significant.    During the fiscal years ended March 31, 2025 and 2026, certain subsidiaries of MHFG partially withdrew assets from employee retirement benefit trusts, which were established for the payment of employees’ severance pay and retirement pensions. Overall, the trusts remain in overfunded status as of March 31, 2026. No gains or losses have been recognized as a result of these transactions.The ratios disclosed above include a leverage ratio buffer required to be met at 50% of the additional loss absorbency requirements applied to the Group as a G-SIB under the finalized Basel III reforms.There were no significant revolving line of credit arrangements that converted to term loans during the fiscal year ended March 31, 2025 and 2026.The MHFG Group included premises and equipment classified as held for sale in Other at March 31, 2025.Guaranteed trust principal, included in All other liabilities in the disclosure about consolidated VIEs in the accompanying balance sheets, is a liability of certain consolidated trust arrangements that meet the definition of a VIE for which the MHFG Group provides guarantees for the repayment of principal. 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us-gaap:OtherContractMember us-gaap:DerivativeFinancialInstrumentsAssetsMember 2025-03-31 0001335730 us-gaap:OtherAssetsMember 2026-03-31 0001335730 us-gaap:AvailableforsaleSecuritiesMember us-gaap:OtherThanSecuritiesInvestmentMember 2026-03-31 0001335730 mfg:NonJapaneseCorporateBondsMember us-gaap:AvailableforsaleSecuritiesMember 2026-03-31 0001335730 mfg:JapaneseCorporateBondsMember us-gaap:AvailableforsaleSecuritiesMember 2026-03-31 0001335730 us-gaap:AvailableforsaleSecuritiesMember us-gaap:CommercialMortgageBackedSecuritiesMember 2026-03-31 0001335730 us-gaap:AvailableforsaleSecuritiesMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2026-03-31 0001335730 us-gaap:OtherContractMember us-gaap:DerivativeFinancialInstrumentsAssetsMember 2026-03-31 0001335730 us-gaap:DerivativeFinancialInstrumentsAssetsMember mfg:CreditRelatedContractsMember 2026-03-31 0001335730 us-gaap:DerivativeFinancialInstrumentsAssetsMember us-gaap:EquityContractMember 2026-03-31 0001335730 us-gaap:ForeignExchangeContractMember us-gaap:DerivativeFinancialInstrumentsAssetsMember 2026-03-31 0001335730 us-gaap:DerivativeFinancialInstrumentsAssetsMember us-gaap:InterestRateContractMember 2026-03-31 0001335730 mfg:TradingSecuritiesMember us-gaap:EquitySecuritiesMember 2026-03-31 0001335730 us-gaap:AllOtherCorporateBondsMember mfg:TradingSecuritiesMember 2026-03-31 0001335730 us-gaap:OtherLiabilitiesMember 2026-03-31 0001335730 us-gaap:LongTermDebtMember 2026-03-31 0001335730 us-gaap:NoncontrollingInterestMember 2026-03-31 0001335730 mfg:OtherRetainedEarningsMember 2026-03-31 0001335730 us-gaap:ParentMember 2026-03-31 0001335730 us-gaap:CommonStockMember 2026-03-31 0001335730 us-gaap:TreasuryStockCommonMember 2026-03-31 iso4217:JPY xbrli:shares utr:Year xbrli:pure utr:Day utr:Month mfg:Segment iso4217:JPY xbrli:shares mfg:Loans\n\n \n\nUNITED STATES SECURITIES AND EXCHANGE COMMISSION\n\nWashington, D.C. 20549\n\n \n\n \n\nFORM\n20-F\n\n \n\n \n\n(Mark One)\n\n \n\n☐\n\nREGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nOR\n\n \n\n☒\n\nANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\n   For the fiscal year ended March 31, 2026\n\nOR\n\n \n\n☐\n\nTRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nOR\n\n \n\n☐\n\nSHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\n  Date of event requiring this shell company report\n\n      For the transition period from   to   \n\nCommission file number\n001-33098\n\nKabushiki Kaisha Mizuho Financial Group\n\n(Exact name of Registrant as specified in its charter)\n\nMizuho Financial Group, Inc.\n\n(Translation of Registrant’s name into English)\n\nJapan\n\n(Jurisdiction of incorporation or organization)\n\n1-5-5\n\nOtemachi\n\nChiyoda-ku, Tokyo\n100-8176\n\nJapan\n\n(Address of principal executive offices)\n\nHikaru Osuga,\n\n+81-3-5224-1111,\n\n+81-3-5224-1059,\n\naddress is same as above\n\n(Name, Telephone, Facsimile number and Address of Company Contact Person)\n\n \n\n \n\nSecurities registered or to be registered pursuant to Section12(b) of the Act.\n\n \n\nTitle of each class\n\n \n\nTrading Symbols\n\n \n\nName of each exchange on which registered\n\nAmerican depositary shares, each of which represents two shares of common stock\n\nCommon Stock, without par value*\n\n \n\nMFG\n\n \n\nThe New York Stock Exchange\n\nSecurities registered or to be registered pursuant to Section12(g) of the Act.\n\nNone\n\n \n\n(Title of Class)\n\nSecurities for which there is a reporting obligation pursuant to Section15(d) of the Act:\n\nNone\n\n \n\n(Title of Class)\n\nIndicate the number of outstanding shares of each of the issuer’s classes of capital or common stock as of the close of the period covered by the annual report.\n\nAt March 31, 2026, the following shares of capital stock were issued: 2,489,848,594 shares of common stock (including\n47,954,672\nshares of common stock held by the registrant as treasury stock).\n\n \n\n \n\nIndicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.\n\nYes ☒ No ☐\n\nIf this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934.\n\nYes ☐ No ☒\n\nNote—Checking the box above will not relieve any registrant required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 from their obligations under those Sections.\n\nIndicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.\n\nYes ☒ No ☐\n\nIndicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation\nS-T\n(§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).\n\nYes ☒ No ☐\n\nIndicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a\nnon-accelerated\nfiler, or an emerging growth company. See definition of “large accelerated filer, “accelerated filer,” and “emerging growth company” in Rule\n12b-2\nof the Exchange Act.\n\n \n\nLarge accelerated filer ☒\n  \nAccelerated filer ☐\n  \n\nNon-accelerated filer ☐\n\n  \nEmerging growth company ☐\n\nIf an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards† provided pursuant to Section13(a) of the Exchange Act. ☐\n\n \n\n†\n\nThe term “new or revised financial accounting standard” refers to any update issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, 2012.\n\nIndicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒\n\nIf securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐\n\nIndicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to\n§240.10D-1(b). ☐\n\nIndicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing:\n\n \n\nU.S. GAAP ☒\n  \nInternational Financial Reporting Standards as issued by the International Accounting Standards Board ☐\n  \nOther ☐\n\nIf “Other” has been checked in response to the previous question, indicate by check mark which financial statement item the registrant has elected to follow."}