Steward has worked at the FCA since 2015 and has been involved in some of the body's most high-profile enforcement cases, as well as leading the FCA's listing authority and oversight of the UK's publicly traded markets, and developing the FCA’s data-led approach to market oversight.
Before joining the FCA, Steward held a position at the Hong Kong Securities and Futures Commission, as well as various senior positions within the Australian Securities and Investments Commission.
FCA chief executive Nikhil Rathi said: "Mark has brought his formidable experience as a regulator and as a litigator to the FCA, delivering significant enforcement cases across a broad spectrum, as well as the FCA's data-led approach to market oversight.
"That enormous contribution is a result of Mark's abiding belief in fairness, that markets must be clean if the economy is to thrive and in doing the right thing on behalf of consumers. He has shown that the FCA is willing to take on challenging cases, will use the full extent of our powers and will deliver results that have a real impact for the markets we oversee and for those who rely on them.
"I am hugely grateful for Mark's leadership, dedication and expertise and wish him the very best for the future."
Steward added: "It has been a privilege to serve the FCA throughout many challenges over the last seven years and, as I move on, to leave behind such a strong team for the future."
The FCA said that the search for Steward’s replacement will begin shortly.
