Aon plc (AON) Business

Item 1. Business

OVERVIEW

Aon plc (which may be referred to as “Aon,” the “Company,” “we,” “us,” or “our”) is a leading global professional services firm. Through actionable analytic insight, globally integrated Risk Capital and Human Capital expertise and locally relevant solutions, our colleagues provide clients with the clarity and confidence to make better risk and people decisions that protect and grow their businesses.

With clients around the world facing growing uncertainty and volatility, we remain focused on accelerating our Aon United strategy to serve clients as one globally connected firm and driving innovation to address unmet and evolving client need. We serve clients in more than 120 countries across all market segments and nearly every industry. This diversification of our client base helps provide our firm with stability in different economic scenarios that could affect specific industries, customer segments, or geographies.

We continue to focus our portfolio on higher-margin, capital-light professional services businesses that have high recurring revenue streams and strong cash flow generation. We endeavor to make capital allocation decisions in order to maximize value for Aon and its shareholders.

BUSINESS SEGMENTS

We manage our business within two reportable segments: Risk Capital and Human Capital. In 2025, our consolidated Total revenue was $17,181 million. This includes $11,290 million in Risk Capital and $5,907 million in Human Capital before certain intercompany eliminations.

Principal Products and Services

Risk Capital

Commercial Risk Solutions uses Risk Capital’s extensive data and analytics capabilities to provide brokerage and consulting services that help organizations develop, improve, and implement their risk management strategies. Commercial Risk Solutions includes insurance and specialty brokerage, global risk consulting, captives management, and Affinity programs. In insurance brokerage, our dedicated teams of risk professionals utilize comprehensive analytics to design strategically resilient insurance programs and provide our clients access to Aon’s proprietary facilities, such as Aon Client Treaty and all other forms of capital, regardless of insurance carrier, placement structure or geography. Throughout the year, we review analytics specific to clients’ losses and exposures, and we evaluate new risk transfer techniques to be considered in the current market conditions. Commercial Risk Solutions is organized around industry and product, including but not limited to property, casualty, financial and professional lines, construction, transportation, energy, cyber, surety, trade credit, crisis management, transaction liability, and climate. Aon’s Global Risk Consulting and Captive Management teams use quantitative analytics to advise on the trade-offs between risk retention and risk transfer as well as to provide claims consulting and advocacy to ensure optimal financial recovery. Aon’s Affinity business collaborates with sponsored groups and other distribution channels to develop, market, and administer customized insurance programs. Commercial Risk’s global reach enables seamless client service in all geographies including Aon’s Global Broking Centers in London, Bermuda, and Singapore. Additionally, in 2025 Aon launched its proprietary Data Center Lifecycle Insurance Program designed to support data center projects from construction through ongoing operations by bringing together traditionally fragmented risk classes into a single coordinated insurance solution.

Reinsurance Solutions includes treaty reinsurance, facultative reinsurance, Strategy and Technology Group and capital markets. Treaty reinsurance addresses underwriting and capital objectives on a portfolio level, allowing our clients to more effectively manage the combination of premium growth, return on capital, and rating agency interests on an integrated basis. This includes the development of more competitive, innovative, and efficient risk transfer options. Facultative reinsurance empowers clients to better understand, manage, and transfer risk through innovative facultative solutions and provides the most efficient access to the global facultative reinsurance markets. Strategy and Technology Group combines strategic advice with data-driven consulting, analytics, and modeling tools, including Capital Insights Explorer, ReMetrica, and PathWise, to help clients deploy capital efficiently and effectively. We develop highly customized solutions, enabled by innovative technology, that help clients drive growth and operational efficiency, improve balance sheet strength and resiliency, and comply with regulatory and operational requirements, including through the execution of reinsurance transactions. Capital markets is a global investment bank with expertise in insurance-linked securities, capital raising, strategic advice, restructuring, and mergers and acquisitions. We partner with insurers, reinsurers, investment firms, and corporations in executing innovative risk management products, capital market solutions, and corporate finance advisory services.

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Human Capital

Health Solutions includes consulting and brokerage, consumer benefits, compensation, and talent advisory services. Consulting and brokerage develops and implements innovative, customized health and benefits strategies for our clients to manage risk, drive engagement, and strengthen their workforce through improved health and wellbeing. We partner with insurers and other strategic partners to develop and implement new and innovative solutions and leverage world-class analytics and technology to help clients make informed decisions and manage healthcare outcomes. Consulting and brokerage also advises multinational companies on global benefits programs, including program design and management, financing optimization, and enhanced employee experience, as well as assists in navigating global regulatory and compliance requirements in over 120 countries. Consumer benefits solutions designs and delivers innovative voluntary consumer benefits programs that improve an employer’s total rewards strategy and positively impacts their employees’ financial and overall wellbeing. We leverage our proprietary digital platform to provide efficient enrollment strategies through an effective combination of data, analytics, and tailored products. Our talent team delivers data, analytics, and advice to business leaders so they can make better workforce decisions and align their business and people strategies. We support clients across the full employee lifecycle, including talent assessment and selection, compensation benchmarking, total rewards strategy optimization, Corporate Governance and strategic employee communications. We also consult on corporate sustainability matters, supporting a wide range of risk assessment and advisory solutions designed to address and manage corporate sustainability issues and enable our clients to create long-term value.

Wealth Solutions includes retirement consulting, pension administration, and investments consulting. Retirement consulting provides clients strategic design advice, actuarial services, risk management solutions including pension risk transfer, and integrated pension administration. Our investments advisory team provides corporations, public pensions, endowments and foundations with advice on developing and maintaining investment programs across a broad range of plan types, including defined benefit plans and defined contribution plans. With respect to defined contributions, we offer Master Trusts and Pooled Employer Plans. Our delegated investment solutions provide ongoing management of investment programs in both partial or full discretionary models. We partner with clients leveraging our expertise and scale to help them effectively manage their investment portfolio.

Revenue and Compensation

Our business generates revenues primarily through commissions, compensation from insurance and reinsurance companies for services we provide to them, and fees from customers. Commissions and fees for brokerage services vary depending upon several factors, which may include the amount of premium, the type of insurance or reinsurance coverage provided, the particular services provided to a client, insurer, or reinsurer, and the capacity in which we act. Compensation from insurance and reinsurance companies includes: (1) fees for consulting and analytics services, and (2) fees and commissions for administrative and other services provided to or on behalf of insurers and reinsurers. Fees from clients for advice and consulting services are dependent on the extent and value of the services we provide. Payment terms are consistent with current industry practices.

Funds Held on Behalf of Clients

We typically hold funds on behalf of clients, including premiums received from clients and claims due to clients that are in transit to and from insurers. Certain funds held on behalf of clients are invested in interest-bearing premium trust accounts and can fluctuate significantly depending on when we collect and remit cash. The principal is segregated and not available for general operating purposes, although we may earn interest on these accounts.

Competition

Our business operates in a highly competitive and fragmented environment. We compete with numerous other global insurance brokers and consulting companies, including, among others, Marsh McLennan, Willis Towers Watson, Arthur J Gallagher & Company, and Lockton Companies, Inc., as well as numerous other global, regional, and local firms in almost every area of our business. We also compete with insurance and reinsurance companies that directly market and service their insurance products without the assistance of brokers or agents. Additionally, we compete with other businesses that do not fall into the categories above, including large financial institutions and independent consulting firms and consulting organizations affiliated with accounting, information systems, technology, human resources, and financial services firms.

Seasonality

Due to buying patterns and delivery of certain products and services in the markets we serve, revenues recognized tend to be higher in the first and fourth quarters of each fiscal year.

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Licensing and Regulation

Our business activities are subject to licensing requirements and extensive regulation under the laws of countries in which we operate, including U.S. federal and state laws. See the “Risk Factors” section in Part I, Item 1A of this report for information regarding how actions by governmental and regulatory authorities or changes in legislation and regulation in the jurisdictions in which we operate may have an adverse effect on our business.

Regulatory authorities in the U.S. and most other countries in which our operating subsidiaries conduct business may require individuals, entities, and related service providers to obtain a license from a government agency, including (but not limited to) licenses to operate as insurance producers, brokers, agents, consultants, reinsurance brokers, or managing general agents.

Certain jurisdictions issue licenses only to resident entities or individuals. In such jurisdictions, if the Company has no licensed subsidiary, we 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.

Our subsidiaries must comply with laws and regulations of the jurisdictions in which they do business. These laws and regulations are enforced by the FCA in the U.K., by federal and state agencies in the U.S., and by various regulatory agencies and other supervisory authorities in other countries through the granting and revoking of licenses to do business, the licensing of agents, the monitoring of trade practices, policy form approval, limits on commission rates, and mandatory remuneration disclosure requirements.

Insurance authorities in the U.K., U.S., and certain other jurisdictions in which our subsidiaries operate have 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 generally require the segregation of these fiduciary funds and limit the types of investments that may be made with them.

Investment, securities, and futures licensing authorities also govern certain business activities. For example, in the U.S., we use Aon Securities LLC, an indirect, wholly owned subsidiary of Aon, and a U.S.-registered broker-dealer and investment advisor, member of FINRA and Securities Investor Protection Corporation, for investment banking, capital advisory services and other broker-dealer activities. Similar operations exist in other jurisdictions outside of the U.S.

Further, pension and financial laws and regulations, including oversight and supervision by the FCA in the U.K., the SEC and the DOL in the U.S., and regulators in other countries govern certain of the retirement-related consulting services provided by Aon and its subsidiaries and affiliates. This includes Aon subsidiaries that provide investment advisory services regulated by various U.S. federal authorities including the SEC, DOL, and FINRA, as well as authorities on the state level. In addition, other services provided by Aon and its subsidiaries and affiliates, such as trustee services and retirement and employee benefit program administrative services, are subject in various jurisdictions to pension, investment, securities, and insurance laws and regulations, and supervision.

Clientele

Our clients operate in many businesses and industries throughout the world. Our single largest client by revenue accounted for approximately 1% of our Total revenue in 2025. Additionally, we place insurance with many insurance carriers, none of which individually accounted for more than 10% of the total premiums we placed on behalf of our clients in 2025.

Aon United, Our Culture, and Human Capital Management Strategy

Our Culture

Our culture is driven by our values – committed as one firm to our purpose, united through trust and integrity as one team, and passionate about making our colleagues and clients successful. Our colleagues are the cornerstone of our success. Collaboration and innovation drive our culture, bringing the best of Aon to clients in a holistic and seamless manner. Our Aon United strategy defines how our colleagues work together to deliver value to clients, setting a new standard for client leadership. Aon United is brought to life through our common client value creation model which scales strategies from across the firm, through our Risk Capital and Human Capital solutions, to bring the best of Aon to clients. Each year, Aon makes significant philanthropic contributions to thousands of organizations and supports numerous colleague volunteer opportunities. As a leading global firm – which is going further, faster to accelerate our Aon United strategy through our 3x3 Plan, which we announced in 2023 – we are focused on attracting, developing and retaining the best talent from all backgrounds, to support our clients and grow our firm.

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Our Colleagues

As of December 31, 2025, we employed approximately 60,000 employees and conducted our operations in more than 120 countries. Our colleagues’ breadth of talent, expertise, and insights contribute to the success of both our firm and our clients, and we seek to attract, develop, and retain the best talent in the industry. Our colleagues are the driving force of our Aon United Strategy. All our colleagues are called upon to be leaders in embracing and modeling our Aon United values and behaviors. By giving transparency into the expectations of behavior as well as accountability for contributing to our Speak Up culture, we ensure that all colleagues – at every stage of their career journey – are equipped and motivated to deliver on our purpose and able to achieve their full potential in an ethical manner. Our colleague experience ensures that colleagues feel more relevant, connected and valued which creates a greater sense of belonging.

We believe that colleagues who feel valued produce better insight, better solutions, and, ultimately, the best outcomes for clients and our long-term success. This is why we are committed to promoting a culture and sense of belonging where colleagues can bring their authentic selves to work, where opportunity and success are driven by their capability and behavior, and where our operations reflect the clients, colleagues and communities we serve around the world. Our commitment to building a culture where each colleague can thrive starts from the top with our Board, including its People & Wellbeing Sub-Committee. Our colleague-led Business Resource Groups also support execution and provide additional opportunities for colleagues to connect and deepen relationships.

As of December 31, 2025, our global workforce was 56% women and 44% men, and the Aon Executive Committee, which leads the firm was 53% women and 47% men. At the manager level, 30% of senior leaders and 46% of managers are female and 70% of senior leaders and 54% of managers were male. New colleague hires for the year were 53% women and 47% men. Our U.S. workforce was 23% racially or ethnically diverse, calculated as a percentage of colleagues that have voluntarily disclosed their race or ethnicity to Aon. At the manager level, 12% of U.S. senior leaders and 18% of U.S. managers with one or more direct report were racially or ethnically diverse.

Apprenticeship programs help build a talent pipeline of highly skilled professionals while providing apprentices with advanced education and work experience. By removing some of the traditional barriers to entry-level employment, as a firm we can contribute to local workforce development and cultivate talent while improving retention rates in these entry-level roles. As a founding member of ten apprentice networks within the U.S., we partner with companies and organizations to assist them in building their own programs through sharing best practices and learnings. Across these networks, we have over 200 organizations committed as of December 31, 2025, committed to 10,000 total apprenticeships by 2030.

Our two-year Apprenticeship Program, which was implemented in the UK and U.S. in 2012 and 2017, respectively, serves as an alternate route into a permanent role that normally requires a specific degree or professional experience. We provide motivated, high-potential individuals with the required training (on the job and in the classroom), professional skills development, mentorship, and experiential learning to bridge the gap. 900 Aon apprentices have been hired since the inception of the program across the U.S. and U.K. Both programs are certified apprenticeship programs, by the Department of Labor in the U.S. and the Department of Education in the U.K.

Training and Development

We invest deeply in developing the talent needed to stay ahead of industry innovation and to remain a destination employer. Our colleagues have access to a wide range of learning opportunities spanning self-guided courses, immersive virtual programs, and advanced leadership development to support every stage of their career growth. These offerings are intentionally aligned with the Aon United strategy, ensuring colleagues gain the skills and capabilities required to lead with excellence. Through purposeful use of technology and a blend of virtual and in-person learning, we deliver tailored, high-impact development experiences that empower colleagues to thrive and drive meaningful results for our clients.

Colleague Engagement and Retention

Creating an engaging and rewarding experience for our colleagues is more than a priority; it’s fundamental to our success as a firm. We actively seek out and value our colleagues’ perspectives, knowing their feedback is essential for driving growth and creating a workplace where everyone thrives. Our commitment to transparent, ongoing communication is reflected in the dynamic channels we offer, such as open forums and town halls with executive leaders, regular colleague surveys, and meaningful engagement through our Business Resource Groups. These independent and voluntary groups play a powerful role in shaping our culture by providing insight, championing initiatives, and identifying opportunities to deepen our dedication to wellbeing, and belonging. Through these collaborative efforts, we not only listen; we act, ensuring every colleague feels heard, valued, and empowered to contribute to our shared purpose.

Our listening strategy consists of frequent surveys across all stages of a colleague’s career. as well as our annual all colleague support survey which enables us to understand how colleagues are engaging with their teams, the firm, and clients.

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This outreach effort allows us to gather insights more rapidly, take timely action to address feedback, and deliver on the needs of colleagues in real time – ensuring colleagues feel more connected, more valued and more relevant. The pulse surveys for 2025 were focused on topics such as manager and leadership support, delivering on our Aon Story, colleague wellbeing, internal mobility and performance. Feedback from our workforce provides management with a better understanding of evolving colleague viewpoints and ensures we are taking appropriate steps to drive colleague engagement and retention. For discussion of the risks related to the attraction and retention of senior management and other professional personnel, see the “Risk Factors” section in Part I, Item 1A of this report.

Rewards

In addition to an inspired purpose and culture, we are proud to offer our colleagues a total rewards program that combines competitive pay, incentive opportunities, and benefits. Our compensation programs including salary, recognition, cash, and equity incentives are connected to our formal performance management and career development approach. These programs serve to reward colleagues for their Aon United impact both in what they accomplish for clients, colleagues, and shareholders, how they achieve those results and how they deliver on our values. We maintain a global commitment to colleague wellbeing and play a key role in supporting colleagues across the physical, emotional, financial, and social spectrum. Our comprehensive benefit programs are competitive for the markets in which we operate and aligned with our values and culture.

Our compensation philosophy aligns with our Aon United strategy and delivering long-term shareholder value creation. Our executive incentives are based on driving results, delivery of strategic initiatives, and leadership. 20% of executive discretionary incentive compensation is based on quantifiable performance against strategic people priorities, including talent retention, engagement and wellbeing.

Website Access to Reports and Other Information

Our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and any amendments to those reports are made available free of charge through our website (https://www.aon.com) as soon as reasonably practicable after such material is electronically filed with or furnished to the SEC. Also posted on our website are the charters for our Audit, Organization and Compensation, Governance/Nominating, and Finance Committees, and People & Wellbeing Sub-Committee, our Corporate Governance Guidelines, and our Code of Business Conduct. Within the time period required by the SEC and the NYSE, we will post on our website any amendment to or waiver of the Code of Business Conduct applicable to any executive officer or director. In addition, we may announce material information to investors and the marketplace using our investor relations website. While not all of the information that we post to such website is of a material nature, some information could be deemed to be material. Accordingly, we encourage investors, the media, and others interested in our company to review the information that we share on our investor relations page on www.aon.com. The information provided on our website is not part of this report and is therefore not incorporated herein by reference.