Gillian Guy, chief executive of Citizens Advice, is to step down after a decade in the role.
The charity said today that Guy would leave in October to become the Independent Assessor for the Financial Ombudsman Service.
Citizens Advice said Guy, who joined the charity from Victim Support in July 2010, had led it through a period of significant growth and digital transformation.
Guy said in a statement she felt “immensely proud and privileged” to have played a part in Citizens Advice.
“I have been fortunate to work with people of passion, commitment and talent, who, with the service itself, have been at the core of my life for the last decade,” she said.
“I am confident that Citizens Advice will continue to go from strength to strength, helping millions of people overcome their challenges in the decades to come.”
Warren Buckley, chair of Citizens Advice, said: “It’s been an honour to work closely with Gillian as she has led Citizens Advice through significant and successful change.
“Gillian leaves Citizens Advice stronger, more resilient and more prepared to deal with whatever the future brings.”
Alistair Cromwell, chief operating officer at Citizens Advice, will become acting chief executive while a permanent successor to Guy is sought.
Guy admitted last year that Citizens Advice had been too slow to make progress on inclusivity and diversity after a report was published on "unacceptable" training material produced by the charity.