McCall is currently on secondment to Saga from the PR agency MHP Communications, where he is chief operating officer.
His role will involve overseeing all direct and indirect communications with Saga’s audiences as a listed business, including 200,000 retail investors.
Stuart Howard, chief financial officer at Saga, said: "Communicating with our existing and potential shareholders will be a key challenge as we embark on an exciting new era as a listed company. Tim’s expertise and approach will be vital in helping us do this and I am delighted that we have been able to secure such a talent for Saga."
McCall was previously a director of financial PR firm Hogarth, which became MHP, and before that managing director of the property PR firm MJ2.
He said: "I have had six great years at Hogarth and then helping to create and grow MHP, but the chance to join a business such as Saga at such an interesting point in its development was too good to resist."
Commenting on his departure, Gavin Devine, chief executive of MHP, said: "Tim has made an immense contribution to the creation and development of MHP, and all of us in the company owe him a great deal. He has been offered a great opportunity and we understand it is too good a chance to turn down."