She was appointed to the position in 2009, having joined from the IMA in 2007and holding the role of director of retail firms division for two years.
During her time as director of conduct policy Nicoll laid the foundations for the new conduct strategy which informed the thinking for how the FCA plans to operate.
She also helped deliver some of the FSA’s flagship policy work on the RDR, mortgage market review and FSCS.
Nicoll said of her departure: “I have spent five challenging but fascinating years at the FSA, through what has arguably been one of the most dramatic periods of change the financial services industry has known.
“Having seen major policy initiatives such as the RDR through to implementation, I feel now is the right time for me to handover to those who will drive the FCA’s policy approach in the future. I will stay with the FSA until the changeover to ensure an orderly handover and then will explore fresh opportunities.”