Katja Hall's role has been made redundant alongside a small number of other senior positions as Capita reduces the size of its operation. Earlier this month the FTSE 250-listed company agreed to sell its speciality insurance businesses to Marco Capital Holdings (UK).
The new structure of the comms department has not been disclosed.
Hall, who leaves her role at the end of the year, said: "Capita's services support millions of citizens up and down the country every day, and it has been a privilege to work alongside my 55,000 colleagues to transform it into a simpler, more focused and financially sustainable business. With the bulk of the transformation complete, this is the right time for me to move on to a new challenge.
"I want to thank Jon [Lewis, Capita chief executive], my brilliant colleagues and my brilliant team for all their support and wish them every success in the future."
Hall joined Capita in 2018 in what was a new role of corporate affairs director. Her remit has included internal and external comms, employee engagement and public affairs.
She joined from Chairman Mentors International, the board-level mentoring organisation, where she was a partner. She was previously at HSBC, where she latterly oversaw global external comms and public affairs.
Prior to that, Hall was deputy director-general of the Confederation of British Industry, where she led its public policy development and advocacy work. She has also worked in human resources at the BBC and is a non-executive director at the Office for Students.