Cornish will replace Mathewson as chairman with immediate effect.
A report in April tipped Cornish to fill the top spot at the bank, which floated on the London Stock Exchange earlier this year.
Previous to his appointment at Shawbrook, Cornish spent 19 years at Yorkshire BS, including eight years as CEO between 2003 and 2011. He went on to become a founding member of the Prudential Regulation Authority board in 2013 and is currently a senior independent director of Arrow Global Group and St James’s Place.
Robin Ashton, independent non-executive director and senior independent director of Shawbrook Bank, said: “We are delighted that Iain is joining the board as chairman, as he brings a wealth of experience and industry knowledge.
“We look forward to his contribution as Shawbrook continues its journey as a public company. We would also like to publicly acknowledge Sir George’s contribution to the founding and growth of Shawbrook over the past four years.”
