Guy Carpenter Reinsurance is the reinsurance arm of Marsh McLennan, focused on global risk and capital solutions. It earned $2.4 billion in revenue in 2024, driven by strong growth in reinsurance broking.
GC Reinsurance was founded in 1922 to apply data-driven risk solutions to reinsurance markets. In 1923, it became part of Marsh McLennan, gaining access to wider financial networks and resources.
The company built its name through analytics, market insights, and bold innovation in global risk transfer. Other important moments in Guy Carpenter Reinsurance’s history include:
- 1940s: developed marine cargo excess-of-loss method, replacing standard treaty practices
- 1950s: devised facultative reinsurance certificate for London placements without cover notes
- 1960s: launched Global Slip Catastrophe product to cover multi-line cedent risks
- 1970s: introduced contract coverage for ECO and Excess of Policy Limits
- 1992: helped form Mid Ocean in Bermuda, raising US catastrophe capacity by 50 percent
- 1999: launched CAT-i reports to deliver real-time catastrophe alerts to clients
- 2005: introduced Capital Adequacy Projector for EU regulatory readiness
- 2013: released China’s first flood modeling maps for 10 cities and lakes
- 2020: supported global pandemic relief with $200 million in surge funding
- 2022: marked 100 years in reinsurance with 60+ offices and 3,400 professionals
In 2025, Guy Carpenter published a major study on cyber risk and regional market growth. It showed that North America held $10.5 billion of the $16.6 billion cyber insurance market.
Guy Carpenter Reinsurance connects global reinsurance specialists and capital strength to deliver smart, risk-focused solutions:
Reinsurance services
- reinsurance broking: helps match risk with capital for growth and stability goals
- strategic advisory: offers tailored guidance using market data and expert risk insights
- global capital solutions: provides access to capital tools from GC Securities and Capital & Advisory
- public sector risk solutions: supports governments in managing large-scale or systemic risk exposures
Risk segments
- property: covers damage-related risk across commercial or personal real estate portfolios
- casualty: addresses liability losses from workplace, public, or product-related incidents
- financial lines: protects against risks in directors, officers, and professional liability
- cyber: provides security for data breaches, digital threats, and business interruption
- climate change: helps clients manage physical and transitional risks tied to climate impact
Client segments
- regional/mutual: custom support for regional carriers with unique local market risks
- MGA/GC Access: solutions for managing general agents through GC Access platform
- public sector: focuses on sovereign, regional, and government-driven reinsurance needs
- life: supports life, annuity, and health portfolios through structured capital strategies
- global clients: delivers consistent strategies for large multinational reinsurance programs
Guy Carpenter Reinsurance helps partners reach capital and growth goals in a changing world. Its expert teams work across markets to solve complex risk with proven reinsurance strategies.
GC Reinsurance builds its culture on resilience, humanity, and humility across all teams and roles. Leadership is viewed as a mindset and is driven by passion, vision, and a commitment to the greater good.
Workplace environment and benefits
The company offers purpose-driven roles in an inclusive space shaped by growth and strong values. Guy Carpenter Reinsurance’s staff also get benefits like:
- career development: Career Pathways tool connects goals with long-term growth and advancement
- compensation and benefits: rewards support physical, financial, and mental wellness for staff and families
- student opportunities: recent grads work on innovation, analytics, and new capital solutions from day one
- rewarding work: early exposure to broking, account work, and stakeholder communication
- inclusive environment: diverse ideas, skills, and backgrounds fuel success and long-term impact
Employees gain hands-on experience and ownership of real work early in their career. That exposure builds confidence, communication skills, and real opportunities to grow.
Diversity and inclusion
Guy Carpenter Reinsurance values inclusion and difference through background, experience, thought, and opportunity. GC Embrace leads this effort by focusing on:
- ethnic and cultural diversity: GC Embrace council on cultural understanding
- gender diversity: GC Embrace council for equal opportunity
- generational diversity: GC Embrace council across age groups
- LGBTQ+ diversity: GC Embrace council for LGBTQ+ inclusion
- mental health, well-being, and disability: GC Embrace council for wellness support
GC Embrace connects colleagues, shares ideas, and builds lasting relationships across teams and regions.
A major tornado outbreak in May 2025 caused heavy insured losses across Missouri, Illinois, and nearby states. Guy Carpenter expects ongoing storm trends to reshape pricing, underwriting, and risk models in reinsurance. The firm continues to track rising weather risks and their growing impact on regional economic losses.
Guy Carpenter Reinsurance sees a more active hurricane season than past long-term averages. Rising sea temperatures and climate patterns may increase storm strength and speed. These insights support smarter reinsurance planning and help clients prepare for complex weather risks.
