Financial report Financial report Form 20 F FY2023 (US GAAP)

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PRESENTATION OF FINANCIAL AND OTHER INFORMATION

In this annual report, the terms "Mizuho Financial Group," the "Mizuho group," "we," "us" and "our" generally refer to Mizuho Financial Group, Inc. and its consolidated subsidiaries, but from time to time as appropriate to the context, those terms refer to Mizuho Financial Group, Inc. as an individual legal entity.

Furthermore, unless the context indicates otherwise, these references are intended to refer to us as if we had been in existence in our current form for all periods referred to herein.

On July 1, 2013, a merger between the former Mizuho Bank, Ltd. and the former Mizuho Corporate Bank, Ltd. came into effect with the former Mizuho Corporate Bank as the surviving entity, which was renamed Mizuho Bank upon the merger. In this annual report, "Mizuho Bank" refers to the post-merger entity, while the "former Mizuho Bank" and the "former Mizuho Corporate Bank" refer to pre-merger Mizuho Bank and pre-merger Mizuho Corporate Bank, respectively.

In this annual report, "our principal banking subsidiaries" refer to Mizuho Bank and Mizuho Trust & Banking Co., Ltd.

In this annual report, references to "U.S. dollars," "dollars" and "$" refer to the lawful currency of the United States and those to "yen" and "¥" refer to the lawful currency of Japan.

In this annual report, yen figures and percentages presented in accordance with accounting principles generally accepted in the United States, or U.S. GAAP, have been rounded to the figures shown, and yen figures and percentages presented in accordance with accounting principles generally accepted in Japan, or Japanese GAAP, have been truncated to the figures shown, in each case, unless otherwise specified. However, in some cases, figures as of or for the fiscal year ended March 31, 2023 and earlier presented in tables have been adjusted to match the sum of the figures with the total amount, and such figures may also be referred to in the related text. We no longer make such adjustments beginning with figures as of or for the six months ended September 30, 2023, and thus the sum of the figures as of or for the six months ended September 30, 2023 and after presented herein may not match the total amount.

Our fiscal year end is March 31. References to years not specified as being fiscal years are to calendar years.

Unless otherwise specified, for purposes of this annual report, we have presented our financial information in accordance with U.S. GAAP. Unless otherwise stated or the context otherwise requires, all amounts in our financial statements are expressed in yen.

We usually hold the ordinary general meeting of shareholders of Mizuho Financial Group in June of each year in Chiyoda-ku, Tokyo.

FORWARD-LOOKING STATEMENTS

We may from time to time make written or oral forward-looking statements. Written forward-looking

statements may appear in documents filed with the Securities and Exchange Commission, including this annual report, and other reports to shareholders and other communications.

The U.S. Private Securities Litigation Reform Act of 1995 provides a "safe harbor" for forward-looking information to encourage companies to provide prospective information about themselves. We rely on this safe harbor in making these forward-looking statements.

This annual report contains forward-looking statements regarding the intent, belief, current expectations and targets of our management with respect to our financial condition and future results of operations. In many cases,

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but not all, we use such words as "aim," "anticipate," "believe," "endeavor," "estimate," "expect," "intend," "may," "plan," "probability," "project," "risk," "seek," "should," "strive," "target" and similar expressions in relation to us or our management to identify forward-looking statements. You can also identify forward-looking statements by discussions of strategy, plans or intentions. These statements reflect our current views with respect to future events and are subject to risks, uncertainties and assumptions. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, our actual results may vary materially from those we currently anticipate. Potential risks and uncertainties include, without limitation, the following:

• international conflicts and geopolitical disruptions;
• increase in allowance for credit losses on loans and incurrence of significant credit-related costs;
• declines in the value of our securities portfolio, including as a result of the declines in stock markets and the impact of the dislocation in the global financial markets;
• changes in interest rates;
• foreign exchange rate fluctuations;
• decrease in the market liquidity of our assets;
• revised assumptions or other changes related to our pension plans;
• a decline in our deferred tax assets;
• the effect of financial transactions entered into for hedging and other similar purposes;
• failure to maintain required capital adequacy ratio levels;
• downgrades in our credit ratings;
• our ability to avoid reputational harm;
• our ability to implement our medium-term business plan and other strategic initiatives and measures effectively;
• the effectiveness of our operation, legal and other risk management policies;
• the effect of changes in general economic conditions in Japan and elsewhere;
• problems related to our information technology systems and cyber attacks;
• amendments and other changes to the laws and regulations that are applicable to us; and
• the effect of climate change.

Our forward-looking statements are not guarantees of future performance and involve risks and uncertainties. Actual results may differ from those in the forward-looking statements as a result of various factors. We identify in this annual report in "Item 3.D. Key Information-Risk Factors," "Item 4.B. Information on the Company-Business Overview," "Item 5. Operating and Financial Review and Prospects" and elsewhere, some, but not necessarily all, of the important factors that could cause these differences.

We do not intend to update our forward-looking statements. We are under no obligation, and disclaim any obligation, to update or alter our forward-looking statements, whether as a result of new information, future events or otherwise.

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PART I

ITEM 1. IDENTITY OF DIRECTORS, SENIOR MANAGEMENT AND ADVISERS

Not applicable.

ITEM 2. OFFER STATISTICS AND EXPECTED TIMETABLE

Not applicable.

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ITEM 3. KEY INFORMATION

3.A. Selected Financial Data

The following table below sets forth selected consolidated financial data of Mizuho Financial Group as of and for the fiscal years ended March 31, 2020, 2021, 2022, 2023 and 2024 derived from the audited consolidated financial statements of Mizuho Financial Group prepared in accordance with U.S. GAAP.

The consolidated financial statements of Mizuho Financial Group as of and for the fiscal years ended March 31, 2020, 2021, 2022, 2023 and 2024 prepared in accordance with U.S. GAAP have been audited in accordance with the standards of the Public Company Accounting Oversight Board (United States) by Ernst & Young ShinNihon LLC, an independent registered public accounting firm.

You should read the selected consolidated financial information presented below together with the information included in "Item 5. Operating and Financial Review and Prospects" and the audited consolidated financial statements, including the notes thereto, included in this annual report. The information presented below is qualified in its entirety by reference to that information.

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Selected Consolidated Financial Information

As of and for the fiscal years ended March 31,

(in millions of yen, except per share data, share number information and percentages)

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As of and for the fiscal years ended March 31,

(in millions of yen, except per share data, share number information and percentages)

Notes:

1. Mizuho Financial Group adopted the share consolidation of the shares of common stock on the basis of one post-consolidation share per ten pre-consolidation shares effective as of October 1, 2020. For purposes of the amounts per share, we have assumed the effective date of the share consolidation to be April 1, 2019.
2. Yen amounts are expressed in U.S. dollars at the rate of ¥107.53= $1.00, ¥110.61= $1.00, ¥121.44= $1.00, ¥132.75= $1.00 and ¥151.22= $1.00 for the fiscal years ended March 31, 2020, 2021, 2022, 2023 and 2024, respectively. These rates are the noon buying rates on the respective fiscal year-end dates in New York City for cable transfers in yen as certified for customs purposes by the Federal Reserve Bank of New York.
3. Figures represent cash dividends per share with respect to the applicable fiscal year. Dividends with respect to a fiscal year include year-end dividends and interim dividends. Declaration and payment of dividends are conducted during the immediately following fiscal year, in the case of year-end dividends, or immediately following interim period, in the case of interim dividends.

3.B. Capitalization and Indebtedness

Not applicable.

3.C. Reasons for the Offer and Use of Proceeds

Not applicable.

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3.D. Risk Factors

Investing in our securities involves a high degree of risk. You should carefully consider the risks described below as well as the other information in this annual report, including our consolidated financial statements and related notes, "Item 5. Operating and Financial Review and Prospects," "Item 11. Quantitative and Qualitative Disclosures about Credit, Market and Other Risk" and "Selected Statistical Data."

Our business, financial condition and operating results could be materially adversely affected by any of the factors discussed below. The trading price of our securities could decline due to any of these factors. This annual report also contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of various factors, including the risks faced by us described below and elsewhere in this annual report. See "Forward-Looking Statements."

Risks Relating to Our Business

We may be adversely affected if economic or market conditions in Japan or elsewhere deteriorate.

We conduct a wide variety of business operations in Japan as well as overseas, including in the United States, Europe and Asia. The outlook for economic and market conditions remains uncertain due to factors such as inflationary trends in the United States and the impact of revision to large-scale monetary easing measures in Japan. If general economic or market conditions in Japan or other regions or countries were to deteriorate or if the financial markets become subject to turmoil, we could experience weakness in our business, as well as deterioration in the quality of our assets. As a result, our financial condition and results of operations could be materially and adversely affected.

International conflicts and geopolitical disruptions may have an adverse effect on us.

Amid the increasingly protracted situation in Ukraine, Japan, the United States and some European countries continue to impose economic sanctions on Russia. Furthermore, concerns about deteriorating US-China relations are growing as the United States and its allies begin to implement more assertive measures against China. In addition, the situation in the Middle East continues to be unstable, and there are concerns about the impact on resource prices. There is also the threat that political developments in various countries and regions will lead to increased division not only among countries, but within countries. Against the backdrop of the growing conflicts and geopolitical disruptions, our clients and suppliers may face challenges of business contraction, volatile prices and supply chain instability and be compelled to reevaluate their business strategies. Moreover, a slowdown in the global economy and a worsening geopolitical situation could lead to declines in corporate earnings and a rise in uncertainty in financial markets, which could result in an increase in our credit- related costs, a decrease in the value of our assets and a negative impact on our liquidity. The increasingly stringent regulations resulting from the geopolitical disruptions could further lead to enhanced regulatory compliance risk and the related risk of reputational damage. As a result of any of the foregoing, our business, financial condition and results of operations may be materially and adversely affected.

Amendments and other changes to the laws and regulations that are applicable to us could have an adverse effect on us.

We are subject to general laws, regulations and accounting rules applicable to our business activities in and outside of Japan. We are also subject to various laws and regulations applicable to financial institutions such as the Banking Act, including capital adequacy requirements, in and outside of Japan. If the laws and regulations that are applicable to us are amended or otherwise changed, such as in a way that restricts us from engaging in business activities that we currently conduct or that requires us to incur additional costs, including costs related to our IT systems, our business, financial condition and results of operations could be materially and adversely affected.

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