Charnley will oversee the captive solutions business, which advises and manages more than 1,200 captives in 44 domiciles globally.
She replaces Nick Durant, who has moved to Guy Carpenter to take on a senior advisory role.
Charnley was previously global sales leader for Marsh Captive Solutions and other Marsh businesses. Before this, she held several roles at the firm including in Hawaii, Arizona, Nevada and Bermuda.
In her new role, she will report to Michael Poulos, client advisory services leader at Marsh.
Poulos said: “In today’s ever-changing, complex risk environment, it is critical that we deliver strategic advice powered by advanced data, analytics, and technology solutions to our captive clients.”
“Ellen Charnley is a proven leader with extensive captive expertise and is ideally suited to lead our practice going forward.”
Charnley added: “I’m thrilled to lead this experienced team of captive professionals and further deliver Marsh’s industry-leading capabilities to help our clients manage risk on their own terms and gain more control over their company’s economic cost of risk.”