NYSE: MRSH

OUR BUSINESSES

RISK AND INSURANCE SERVICES

This segment accounted for approximately 64% of the Company's total revenue in 2025 and employed around 55,700 colleagues globally. It includes Marsh Risk and Guy Carpenter.

MARSH RISK

Marsh Risk is the world's leading insurance broker and risk advisor, offering risk management, insurance broking, insurance program management, risk consulting, analytical modeling and alternative risk financing services to a wide range of businesses, government entities, professional service organizations and individuals in 130 countries. It employs approximately 52,000 colleagues and generated approximately 54% of the Company's total revenue in 2025.

Insurance Broking and Risk Advisory

Marsh Risk offers risk analysis, insurance program design, claims support and alternative risk strategies.

•Risk Management supports clients’ worldwide risk issues, and Specialty supports clients who require advice in highly specialized industry and product areas.

•Corporate serves middle-market clients globally and is also serviced through Marsh McLennan Agency (MMA).

◦Marsh McLennan Agency (MMA) provides business insurance, employee health and benefits, retirement and wealth management and private client insurance solutions to individuals and mid-market organizations. MMA advises on insurance program structure and market dynamics, along with industry expertise and transactional capability. Since its first acquisition in 2009, MMA has acquired more than 135 agencies. MMA also offers wealth and retirement products and services to clients.

•Commercial & Consumer serves clients with less complex risks. This segment includes:

◦Victor Insurance Managers (Victor) serves as underwriting managers of professional liability, catastrophe and other specialty insurance programs worldwide.

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◦Affinity focuses on insurance programs sold to insureds or vendors through a corporate sponsor using an affinity distribution model.

◦High net-worth individuals and family offices are served by MMA in the US and other Marsh personal lines businesses globally.

Additional Services: Marsh Risk also offers specialist advisory services through risk consulting, captive solutions and international placement. Outside the U.S., Mercer and Marsh Risk go to market together to provide health benefits brokerage and consulting services. Within the U.S. and Canada, Marsh Risk advises on health benefits brokerage and consulting services through MMA. Marsh Risk's Insurer Consulting Group (ICG) provides various services to insurance carriers.

GUY CARPENTER

Guy Carpenter, the Company’s reinsurance intermediary and advisor, provides specialized reinsurance broking, strategic advisory and actuarial services, and analytics solutions. It employs approximately 3,700 colleagues and generated approximately 10% of the Company's total revenue in 2025.

Reinsurance and Risk Management Services

Guy Carpenter creates and executes reinsurance and risk management solutions globally through risk assessment analytics, actuarial services and trading relationships with reinsurance markets.

As a broker, Guy Carpenter handles treaty and facultative reinsurance across various sectors and provides alternatives to traditional reinsurance, such as industry loss warranties and capital markets solutions.

GC Securities provides structuring and placement services in respect of insurance-linked securities, such as catastrophe bonds and sidecar vehicles, along with surplus notes. GC Capital & Advisory offers corporate finance solutions, including mergers and acquisitions advice and capital raising, which complement Guy Carpenter's larger capabilities. GC Securities and GC Capital & Advisory are both divisions of MMC Securities LLC.

Reinsurance-related Services

Additionally, Guy Carpenter provides actuarial consulting, contract and claims management, and portfolio analysis, helping clients understand uncertainties and make critical decisions in areas such as reinsurance utilization and capital adequacy.

Compensation for Services in Risk and Insurance Services

Marsh Risk and Guy Carpenter are compensated for brokerage and consulting services through commissions and fees. Commission rates and fees vary in amount and depend on coverage provided, the insurer or reinsurer selected, and the capacity in which the broker acts and negotiates with clients. Marsh Risk also receives other compensation from insurance companies, which includes payments for consulting and analytics services; compensation for administrative and other services (including fees for underwriting services and services related to the administration and management of quota shares, panels and other facilities); payments for participation in sponsorship programs; and contingent commissions, based on factors such as volume or profitability of Marsh Risk's placements, primarily driven by MMA and parts of Marsh Risk's international operations.

Marsh Risk and Guy Carpenter also receive interest income on certain funds (such as premiums and claims proceeds) held in a fiduciary capacity for others. For a more detailed discussion of revenue sources and factors affecting revenue in our Risk and Insurance Services segment, refer to Part II, Item 7 ("Management's Discussion and Analysis of Financial Condition and Results of Operations") of this report.

CONSULTING

This segment generated approximately 36% of the Company's total revenue in 2025 and employed around 29,100 colleagues globally, primarily through Mercer and Marsh Management Consulting.

MERCER

Mercer is a leading provider in delivering advice, solutions and products that help organizations meet the health, wealth and career needs of a changing workforce. It employs approximately 21,900 colleagues and generated approximately 23% of the Company's total revenue in 2025.

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Mercer operates in the following areas:

•Health: assisting employers in managing employee health programs, compliance and outsourcing benefits. Outside of the U.S., Mercer and Marsh Risk go to market together to provide health benefits brokerage and consulting services.

•Wealth: providing actuarial, investment consulting and investment management services for clients’ retirement plans and other investment pools, managing approximately $692 billion in assets worldwide at December 31, 2025.

•Career: advising on employee engagement, skill assessment, executive remuneration, HR effectiveness and M&A strategy utilizing proprietary data and tools.

MARSH MANAGEMENT CONSULTING

Marsh Management Consulting offers management consulting and advisory services across various industries through three industry-leading operating units. It employs over 7,200 colleagues and generated approximately 13% of the Company's total revenue in 2025.

Oliver Wyman includes the following specializations: Actuarial, AI Transformation, Climate and Sustainability, Customer Innovation and Growth, Finance, Risk and Restructuring, Mergers and Acquisitions and Performance Transformation.

Lippincott specializes in brand strategy and design.

NERA Economic Consulting provides economic analysis for complex business and legal issues.

Compensation for Services in Consulting

Marsh Management Consulting is primarily compensated through client fees. Mercer receives client fees and commissions and fees based on assets or members. In the majority of cases, Mercer's Health business is compensated through commissions for the placement of insurance contracts and supplemental compensation from insurers based on various factors as volume, growth of accounts, and total retention of accounts placed by Mercer. Mercer's investments business and certain of its administration services are compensated based on assets under administration or management or fee per member. For a majority of the Mercer-managed investment funds, revenue received from Mercer's investment management clients as sub-advisor fees is reported on a gross basis rather than on a net basis. For a more detailed discussion of revenue sources and factors affecting revenue in the Consulting segment, refer to Part II, Item 7 ("Management's Discussion and Analysis of Financial Condition and Results of Operations") of this report.

REGULATION

The Company's activities are subject to licensing requirements and extensive regulation under US federal and state laws, as well as laws of other countries in which the Company operates. Across most jurisdictions, we are subject to data privacy and data protection laws and regulations that apply to personal information, as well as cybersecurity laws and regulations and emerging laws and regulations related to artificial intelligence ("AI"). Additionally, we are subject to various financial crime laws and regulations through our activities of associated persons, the products and services we provide and our business and client relationships. Such laws and regulations relate to, among other areas, sanctions and export control, anti-bribery, anti-corruption, anti-money-laundering and counter-terrorist financing. In certain circumstances, we are also required to maintain operating funds primarily related to regulatory requirements outside the U.S. See Part I, Item 1A ("Risk Factors" below for a discussion of how actions by regulatory authorities or changes in legislation and regulation may have an adverse effect on our businesses and for more information about the laws and regulations related to data privacy, data protection, cybersecurity and AI and the associated risks to our businesses.

Risk and Insurance Services. All U.S. states and most foreign jurisdictions require insurance market intermediaries and related service providers (such as insurance brokers, agents and consultants, reinsurance brokers and managing general agents) to hold an individual or company license from a government agency or self-regulatory organization. Some jurisdictions issue licenses only to individual residents or locally owned business entities; in those instances, the Company may maintain arrangements with residents or business entities licensed to act in such jurisdiction. Such arrangements are subject to an internal review and approval process.

Licensing of reinsurance intermediaries is generally less rigorous compared to that of insurance brokers, and most jurisdictions require only corporate reinsurance intermediary licenses.

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Our business is regulated by the Financial Conduct Authority ("FCA") in the U.K. The FCA licenses insurance and reinsurance intermediaries and evaluates related criteria such as professional competence, financial capacity and professional indemnity insurance requirements, as well as the broking of premium finance to consumers. It enforces prohibitions on anti-competitive behavior in financial services.

Insurance authorities in the U.S. and certain other jurisdictions, including the FCA in the U.K., have also enacted laws and regulations governing the investment of funds, such as premiums and claims proceeds, held in a fiduciary capacity for others. These laws and regulations provide for the segregation of these fiduciary funds and limit the types of investments that may be made with them; they generally apply to both the insurance and reinsurance business.

Other regulatory bodies, such as investment, securities, and futures licensing authorities, govern certain of the Company's Risk and Insurance services activities.

•MMC Securities LLC is a SEC registered broker-dealer and introducing broker used by Marsh Risk and Guy Carpenter in the U.S., primarily in connection with capital markets and other investment banking-related services relating to insurance-linked and alternative risk financing transactions. It is a member of the Financial Industry Regulatory Authority ("FINRA"), the National Futures Association and the Securities Investor Protection Corporation ("SIPC”).

•MMA Securities LLC is a SEC-registered broker-dealer and investment adviser used by Marsh Risk in the U.S. that provides investment advisory and consulting services to employee-sponsored retirement plans. It is a member of FINRA, SIPC and the Municipal Securities Rulemaking Board ("MSRB").

•MMA Asset Management LLC is a SEC-registered investment advisor used primarily in connection with retirement and wealth management.

•Precept Advisory Group LLC is a SEC-registered investment advisor providing investment advisory and consulting services to employee-sponsored retirement plans.

•MMC Securities Limited is authorized and regulated by the FCA to provide advice on securities and investments in the U.K.

•MMC Securities (Ireland) Limited is authorized and regulated by the Central Bank of Ireland and used by Guy Carpenter to place certain securities and investments in the European Economic Area.

MMC Securities LLC, MMC Securities Limited, MMC Securities (Ireland) Limited, MMA Securities LLC, Precept Advisory Group LLC and MMA Asset Management LLC are indirect, wholly-owned subsidiaries of Marsh & McLennan Companies, Inc.

MMA's health brokerage and consulting business and wealth and retirement business are subject to the similar regulatory regimes for Mercer's Health and Investments business, as described in more detail below.

Consulting. Mercer's retirement consulting and investment services are subject to pension law and financial regulation. In certain countries, Mercer relies on licensed colleagues or registered legal entities to engage in these services or uses other Marsh entities or third parties. Mercer’s trustee services, investment services (including advice to persons, institutions and other entities on the investment of pension assets and assumption of discretionary investment management responsibilities) and retirement and employee benefit program administrative services provided by Mercer and its subsidiaries and affiliates may be subject to investment and securities regulations, including (but not limited to) regulations imposed or enforced by the Securities and Exchange Commission (SEC) and the U.S. Department of Labor, the Ontario Securities Commission, the FCA, the Central Bank of Ireland, the Australian Prudential Regulation Authority and the Australian Securities and Investments Commission.

•Mercer Investments LLC is a registered investment advisor which consolidates the activities of Mercer’s affiliated investment adviser entities in the U.S.

•Mercer Trust Company is a limited-purpose New Hampshire chartered trust bank that provides services for certain clients of Mercer’s investment management business in the U.S.

Mercer’s benefits insurance consulting and brokerage services are subject to the same licensing requirements and regulatory oversight as the insurance market intermediaries described above regarding our Risk and Insurance businesses. Depending on the client and services rendered, Mercer may also be subject to direct oversight by the Department of Health and Human Services and other federal agencies in the U.S. Mercer

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provides annuity buy-out advice that is subject to regulations (for example, in the U.S., state insurance licensing regulations and ERISA). Mercer uses the services of MMC Securities LLC to provide certain services, including executive benefit and compensation services and securities dealing services.

FATCA. Regulations promulgated by the U.S. Treasury Department pursuant to the Foreign Account Tax Compliance Act and related legislation (FATCA) require the Company to take various measures relating to non-U.S. funds, transactions and accounts. The regulations impose certain client financial account obligations on Mercer and MMA relating to non-U.S. financial institution and insurance clients.

COMPETITIVE CONDITIONS

The Company faces intense competition across all its businesses, from providers of similar services to competition from third parties in identifying acquisition targets. Competition is based on service sophistication, range, quality, and cost. Attracting and retaining qualified colleagues is also highly competitive and competition for talent continues to intensify. The landscape varies across geographies, industries, and market segments, as detailed in "Risks Relating to the Company Generally — Competitive Risks" in Part I, Item 1A.

In insurance and reinsurance, the Company encounters strong competition from other insurance and reinsurance brokerage firms operating on a global, regional, national or local scale, from independent insurance and reinsurance companies that market, distribute and service their products without the assistance of brokers and from other businesses, including commercial and investment banks, consultants, and online platforms, to traditional insurance brokerage services. The entry of third-party capital providers and clients opting for self-insurance or direct coverage further intensifies competition. Certain insureds and groups of insureds have established programs of self-insurance as a supplement or alternative to purchasing traditional third-party insurance placements. Certain insureds also obtain coverage directly from insurance providers. Managing general agents, affinity programs, and private client services also compete with the Company's offerings.

The consulting business faces competition from global, regional and local firms, including independent consulting, broking and outsourcing firms affiliated with accounting, technology and financial services and new entrants utilizing generative AI. Mercer’s Health division competes with insurers and non-traditional entrants, such as consumer businesses and digital consultancies. Its investment services face competition from investment consulting firms, asset managers, and financial institutions, with some clients choosing to manage services provided by Mercer and Marsh Management Consulting internally.

Segmentation of Activity by Type of Service and Geographic Area of Operation.

Financial information relating to the types of services provided by the Company and the geographic areas of its operations is incorporated herein by reference to Note 17, Segment Information, in the notes to the consolidated financial statements included under Part II, Item 8 of this report.

HUMAN CAPITAL

We believe the health of our business relies on the strength of our workforce, embodied by our Colleague Value Proposition: You can be your best here. This statement captures the unique experience offered to our current and prospective colleagues, drawing inspiration from the voices of our own colleagues. It is embodied in our key pillars: Impact, Leadership, Culture, Career, and Rewards, all of which support our shared purpose: "We build the confidence to thrive through the power of perspective."

Our People. As of December 31, 2025, the Company and its consolidated subsidiaries employed more than 95,000 colleagues worldwide, including approximately 55,700 in Risk and Insurance Services and 29,100 in Consulting.

People Leadership and Governance. The Chief People Officer leads our people strategy, focusing on talent attraction, development and engagement. This includes attracting, recruiting, hiring, developing and engaging talent and designing colleague total rewards programs. The Chief People Officer also leads our approach to inclusion. Our Business Responsibility Committee and Compensation Committee of the Board of Directors have oversight responsibility for various aspects of the Company’s human capital management and are regularly updated by the Chief People Officer.

Talent & Culture. Our Company’s greatest strength is the collective talent of our people. We support talent development through regular discussions, career development workshops, Global Learning Day events and our AI Academies to enable all colleagues to advance their skills. Since the launch of our AI Academy in August 2024,

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more than 46,000 colleagues have received their AI Academy credentials. In July 2025, we also launched the leadership Mindset Academy, with nearly 15,000 colleagues having completed the program with the aim of enhancing their leadership skills at every stage of their career. We also delivered more than 400 in-person and virtual workshops, aimed at strengthening professional and client skills, people management and leadership capabilities. Our two Global Learning Days brought more than 100 learning experiences to approximately 20,000 attendees across the organization. Since 2011, we have conducted annual colleague surveys to gauge satisfaction and identify areas for improvement. In 2025, we aligned the question set to our Colleague Value Proposition and expanded people manager access to the survey results.

Health and Well-being. We are committed to a comprehensive colleague value proposition that places colleagues’ health, well-being and work-life balance at its center. Our program provides market-competitive medical and core health coverage, supported by time-off policies aligned with best practices, including an annual paid volunteer day to foster community engagement. Colleagues have access to personalized mental-health resources and 24/7 confidential counseling, ensuring timely and confidential support. In addition, our critical-incident response capability delivers coordinated, rapid assistance to colleagues affected by emergencies or disasters, with regional support tailored to local needs.

Total Rewards. We offer our colleagues rewards designed to be competitive in the market, attract and retain highly talented individuals, and recognize their performance and contributions. Base pay is one component. We further encourage performance that aligns with the Company’s interests by awarding discretionary incentives to eligible colleagues. These incentives, including annual bonuses, sales incentives and long-term incentives, are awarded to colleagues who have a significant impact on our success. Our total rewards also include health and retirement benefits, as well as savings and stock investment plans in most jurisdictions.

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EXECUTIVE OFFICERS OF THE COMPANY

The executive officers of the Company are appointed annually by the Board of Directors. As of February 9, 2026 the executive officers are:

Paul Beswick, age 51, is Senior Vice President and Global Chief Information and Operations Officer (CIOO) of Marsh. As CIOO, Mr. Beswick leads the Business and Client Services team and oversees Marsh's global Operations and Technology teams. Prior to assuming this expanded role in January 2025, Mr. Beswick served as Chief Information Officer from 2021 to 2025. He was previously a Partner and Global Head of Oliver Wyman Labs and the Digital Practice at Oliver Wyman where he worked in various sectors, including financial services, retail, transportation, telecoms, and consumer goods. Before this, Mr. Beswick headed Oliver Wyman's North American Retail Practice.

Katherine J. Brennan, age 47, is Senior Vice President and General Counsel of Marsh. In this role, she leads Marsh’s global legal, compliance and public affairs function, as well as its sustainability efforts. Ms. Brennan has held several legal and compliance leadership roles at the Company, serving most recently as General Counsel of Marsh Risk from 2021 to 2022. She also served as Deputy General Counsel, Corporate Secretary and Chief Compliance Officer for Marsh from 2017 to 2021, and prior to that, as General Counsel of Guy Carpenter. Ms. Brennan currently serves on the Board of the Red Cross of Greater New York.

John Q. Doyle, age 62, is President and Chief Executive Officer of Marsh. Previously, from 2021 to 2022, he served as Group President and Chief Operating Officer, responsible for the strategy and operational objectives of the Company’s four global businesses. He joined in 2016 as President of Marsh Risk, which he subsequently led as President and CEO from 2017 to 2021. Mr. Doyle has 40 years of leadership experience in professional and financial services. He began his career at AIG, where he held several executive-level positions. Mr. Doyle serves as the Chairman of the United States Treasury’s Federal Advisory Committee on Insurance, as a member of the Business Roundtable, on the Board of Directors of the Partnership for New York City and on the Board of Overseers of the Maurice R. Greenberg School of Risk Management, Insurance and Actuarial Science at St. John’s University. He is a Trustee of the Inner-City Scholarship Fund, and a member of the Board of the New York Police and Fire Widows’ and Children’s Benefit Fund.

Carmen Fernandez, age 52, is Senior Vice President and Chief People Officer for Marsh. Prior to her appointment as Chief People Officer in January 2021, Ms. Fernandez held positions within the Company for 15 years, most recently Deputy CHRO, CHRO of Guy Carpenter, and HR leadership roles at Mercer, including North America HR Leader, Global HR Leader for the Career business and Chief of Staff in the Office of the CEO. Before joining Marsh, Ms. Fernandez worked in investment banking at Goldman Sachs and Bank of America. She began her career as a consultant with PricewaterhouseCoopers.

John Jones, age 54, is Chief Marketing and Communications Officer of Marsh. Previously, he served as Chief Marketing and Communications Officer of Marsh Risk from 2018 to 2022. Mr. Jones joined the firm in 2016 as Senior Vice President of Business Planning, leading strategic planning and global growth initiatives. Prior to that, Mr. Jones was senior vice president of commercial marketing and strategy for AIG and has more than 25 years of marketing, communications and strategy experience.

Dean Klisura, age 62, is President and Chief Executive Officer of Guy Carpenter, and serves as Vice Chair of Marsh. Prior to assuming this role in January 2022, he was President of Guy Carpenter, overseeing the North America, International, Specialty and Global Analytics & Advisory business units. Previously, Mr. Klisura was President of Marsh Risk Global Placement and Advisory Services, leading property and casualty placement activities globally, as well as leading Bowring Marsh, the Insurer Consulting Group, and Marsh Risk Consulting. He joined Marsh Risk in 1993 and held several key global leadership roles, including President of Global Specialties.

Mark McGivney, age 58, is Senior Vice President and Chief Financial Officer of Marsh. Prior to assuming this role in January 2016, Mr. McGivney held several senior financial management positions since joining the Company in 2007. Most recently, he was Senior Vice President, Corporate Finance of Marsh, and was responsible for leading and directing the Company’s Corporate Development, Treasury and Investor Relations functions from 2014 to 2016. Prior to that, he served as Chief Financial Officer of Marsh Risk, and Chief Financial Officer and Chief Operating Officer of Mercer. His experience prior to joining Marsh included senior finance positions at The Hanover Insurance Group as well as positions at Merrill Lynch and PricewaterhouseCoopers.

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Martin South, age 61, is President and Chief Executive Officer of Marsh Risk. He assumed his current role in January 2022 and oversees all of Marsh Risk’s businesses and operations globally. He also serves as Vice Chair of Marsh. Mr. South joined the Company for the first time in 1985 with Bowring Marsh. His industry experience includes senior leadership roles at Zurich Financial Services, where he was a member of the Group Management Board, responsible for all of Zurich’s operations outside of North America and Europe, and CEO of Zurich’s London operations. Since rejoining the Company in 2007, Mr. South has served as CEO of Marsh Risk’s Asia-Pacific region, CEO of Marsh Risk U.K. and Ireland, CEO of Marsh Europe and CEO of Marsh Risk U.S. and Canada.

Nicholas Studer, age 52, is Chief Executive Officer of Marsh Management Consulting and Vice Chair of Marsh. He assumed his current role in July 2021. Mr. Studer was the Managing Partner of the Consumer, Industrial and Services Practice Group from 2017 to 2021, before becoming Managing Partner of Oliver Wyman in 2021. He has held many senior positions at Oliver Wyman, including Managing Partner of the Financial Services Practice Group, Head of the European Finance and Risk Practice and Global Head of the Corporate and Institutional Banking practice. He has over 25 years of consulting experience in the U.K., Continental Europe, and North America. Mr. Studer was a founding Director of TheCityUK, a founding advisory board member of the FICC Markets Standards Board and was a member of the Sustainable Markets Initiative.

Pat Tomlinson, age 55, is President and Chief Executive Officer of Mercer and Vice Chair of Marsh, a position he assumed in April 2024. He also serves as CEO of Marsh U.S. and Canada, with responsibility for leading across businesses to address clients’ increasingly interconnected risk, strategy and people challenges. From 2020 to 2024, Mr. Tomlinson was Mercer's President of U.S. and Canada. Prior to that, he served a business leader in Mercer's U.S. and Canada region, leading the U.S. East Market from 2017 to 2020 and leading the U.S. and Canada Career business from 2014 to 2017. Prior to joining Mercer in 2014, he spent 17 years with Aon and served as an officer in the U.S. Army.

The Company is subject to the information reporting requirements of the Securities Exchange Act of 1934. In accordance with the Exchange Act, the Company files with, or furnishes to, the SEC its annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and proxy statement for its annual shareholders' meeting. The Company makes these reports and any amendments to these reports available free of charge through its website, www.corporate.marsh.com, as soon as reasonably practicable after they are filed with or furnished to the SEC. The SEC also maintains a website at www.sec.gov that contains reports, proxy and information statements and other information regarding issuers, like the Company, that file electronically with the SEC.

The Company also posts certain governance and other information for investors on its website.

The Company encourages investors to visit these websites from time to time, as information is updated and new information is posted. Website references in this report are provided as a convenience and do not constitute, and should not be viewed as, incorporation by reference of the information contained on, or available through, the websites. Therefore, such information should not be considered part of this report.

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