Abercromby joins the mortgage and investment firm from LV=, where he was group finance director.
He has previously held finance director and chief executive roles at Norwich Union Life and Halifax Life.
Abercromby will join the board and report to Sean Oldfield, chief executive officer at Castle Trust, and in his new role will take responsibility for finance, risk and legals.
Abercromby says: “It is great to be part of such an impressive team bringing Castle Trust’s unique propositions to market.”
Oldfield adds: “Keith brings to Castle Trust over a decade of board level experience in successfully managing multi-billion pound balance sheets and consumer propositions across a range of financial services and will be invaluable in delivering strong outcomes for customers and shareholder alike.”
Castle Trust last week unveiled plans to launch into the mortgage market, offering ‘partnership mortgages’ that give borrowers a 20% equity loan in exchange for a share of any increase in the property’s value, subject to receiving Financial Services Authority approval.