Mather joins MasterCard and will report to recently appointed head of comms Neil Henderson.
The move comes after Mather left Samsung, where he was a leading member of the team that delivered the Olympic sponsorship.
Before joining Samsung, Mather worked at Freud Communications and also spent nearly three years at The Red Consultancy.
He has been hired to lead the comms push for The Brits, the Champions League final at Wembley in May and to support MasterCard’s consumer and corporate comms.
Henderson said: ‘Ked is one of Britain’s brightest PR talents. He was a shining star when he came to The Red Consultancy as a grad. I’ve always been impressed by his work ethic, contacts and the ability to work with top talent and he will be key in our huge comms drive in the New Year.'
MasterCard will host pitches from agencies for its six-figure comms account in mid-December.