Principal ombudsman David Thomas will take over at the helm of the FOS until a permanent replacement for Walter Merricks is found.
Thomas will step in as interim chief ombudsman when Merricks departs on 30 October.
Merricks leaves the FOS this month after holding the role of chief ombudsman for ten years to become chair of a new medical tribunal.
Thomas, who has been at the FOS for a decade, will take over as chief ombudsman until a permanent replacement is found. He has previously worked as a banking ombudsman and a solicitor.
The position was first advertised last month, after the FOS spoke to key stakeholders to decide one which skills and experience would be most needed for a new chief ombudsman. Candidates are due to be interviewed in December.
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