Fiona Muldoon is to leave her position as Chief Executive of insurer FBD Holdings.
She has agreed with the board to stay on until October 2020.
Ms Muldoon has been CEO since August 2015, having joined FBD as executive director and chief financial officer at the beginning of 2015.
Commenting on Ms Muldoon's decision to step down, FBD Chairman Liam Herlihy said: "Fiona has transformed the commercial fortunes of FBD over the past four years.
"Her relentless focus on the business and its customers has been remarkable.
"The shareholders and the community we serve have benefited from her tireless efforts. Succession planning is an important Board function and an executive search will commence."
Ms Muldoon said she is "really proud of all that the company has accomplished in the last five years since taking over as CEO.
"We have taken the business through a major repair, recovery and refocus operation through to its current state of strength and stability.
"Our results speak for themselves and I wish the FBD team at Head Office in Bluebell and in our branches up and down the country every continued success as we proudly push on from here as the only independent Irish insurer in the Irish marketplace.
"As I prepare to move on I will endeavour to say goodbye in person to the many loyal colleagues, friends, shareholders and customers that I have met during my time here."
The company said an executive search to find her successor will now commence.
