Mathewson (pictured) will join the firm in April 2018, replacing current CEO Ian Sackfield, who announced in March that he would be stepping down as soon as a replacement had been found.
Sackfield will remain with the business as a client director.
Mathewson will join Brown Shipley after 22 years at Santander where he held several senior positions, most recently as managing director of the wealth management and private banking unit for three years.
He has also held CEO roles at Cater Allen Private Bank, Santander Insurance, Santander Cards and as managing director of Santander’s retail branch network. He began his career with Lloyds Banking Group.
David Rough, chairman of Brown Shipley, said: “I am delighted that Alan is set to join Brown Shipley. He has significant leadership skills, together with both specific wealth management and broad financial services experience, including a successful track record of growing wealth management businesses as a CEO.
“I am confident that, given Alan’s mix of experience, drive and enthusiasm, he will build upon the impressive foundations Brown Shipley has as a UK-wide full-service wealth manager and that he will continue to drive the business forward.”
Rough also thanked Sackfield for his “significant contribution” to Brown Shipley and its success during his time as CEO.
He added: “He has led the business admirably, delivering significant growth in AUM and having successfully integrated recent acquisitions.”
Mathewson said: “I am thrilled to be joining Brown Shipley, a well-established and successful firm with ambitious growth plans.
“I very much look forward to starting the role and building upon Brown Shipley’s long history of success.”