Isio strengthens Employee Benefits leadership with Marcus Slee partner appointment

16 March 2026: Isio has appointed Marcus Slee as Partner and Head of Employee Benefits (EB), as the firm continues to invest in the growth of its technology-enabled benefits offering and strengthen its leadership team.  

Isio’s Employee Benefits practice advises employers on the design, implementation and governance of workplace benefits programmes, helping organisations support employee wellbeing, engagement and financial security. The team combines strategic advice with technology-led solutions to help clients deliver modern, effective benefits experiences for their workforces. 

Marcus Slee brings more than 15 years’ experience working across employee benefits, technology and commercial strategy. He joins from Mercer, where he most recently served as Partner & Digital Leader for Mercer Marsh Benefits (MMB) UK & Europe and was a member of the UK and European leadership team. 

During his time at Mercer, Marcus led the design and delivery of digital strategy across more than 30 European markets, developing and scaling technology-enabled benefits solutions that connect health, wellbeing and rewards ecosystems. He previously held senior leadership roles across Mercer Marsh Benefits, including leading the growth of its UK digital business and overseeing regional digital strategy and commercial performance. Earlier in his career, Marcus spent nearly a decade at Thomsons Online Benefits, where he held various transformation and programme leadership roles focused on scaling global benefits technology platforms and operational capabilities. 

Andrew Coles, Chief Executive of Isio, said: “We are seeing strong and sustained demand from employers for technology-enabled solutions that make benefits more accessible, personalised and impactful for employees. Marcus brings a combination of strategic leadership, digital innovation and expertise in the benefits technology ecosystem. His appointment significantly strengthens our leadership team as we continue to grow our Employee Benefits business and invest in new technology-led solutions for clients.” 

Marcus Slee, Partner, Employee Benefits at Isio, said: “Isio has built a strong reputation for independent advice and innovative thinking across pensions, investment and employee benefits. The opportunity to join a business that is growing rapidly and investing in new solutions for clients is incredibly exciting. 

“Employers are increasingly looking for benefits strategies that are data-driven, digitally enabled and more closely aligned with the needs of their people. I look forward to working with colleagues across Isio to continue developing the firm’s Employee Benefits offering and helping employers provide more engaging and effective benefits experiences for their employees.”