CS Healthcare has hired Andrew Johnston as its new chairman while Mark Rothery, CEO, will leave in the New Year.
Johnston worked at the Government Actuary's Department (GAD) for over 30 years and retired after five years as deputy government actuary and head of pensions in the GAD.
He is also a member of the management board of the World Trade Organisation's pension plan.
In July 2015 CS Healthcare unveiled an 'affordable healthcare' private medical insurance policy.
The former chairman, Sir Bill Jeffrey KCB took up the role in 2011 having previously been an under Secretary of State in the Ministry of Defence, as well as previously working in the Cabinet Office and Northern Ireland Office.
A replacement for Rothery has yet to be announced. Rothery is leaving for a new role in the Channel Islands, he was appointed in June 2014.
Russell Stephens, deputy chief executive officer at CS Healthcare said, "We are very grateful to Bill for the progressive approach he has brought to the Society over the past four years, and we will all miss his wise counsel - as we will Mark, who has had an extremely positive impact on the Society and its standing over the last two years.
"The recent news that we have topped the table of Private Medical Insurance providers for consumer satisfaction in the most recent poll of members conducted by consumers' champion Which? is a fitting testament to Bill and Mark's respective contributions.
"Having worked so closely with Sir Bill and the other Board members over the last two years, Andrew is fully committed to continue to deliver the Society's ‘5 Year Plan', so the transition will be a seamless one."