Richard Lloyd is to step down in May after five years with the company.
He joined Which? in April 2011, and was responsible for a series of high profile, public campaigns that aimed to make positive changes for all consumers.
Mr Lloyd was also responsible for the creation of a brand new range of free to use Which? public service websites helping people to choose their university, where to have a baby or to find care for their elderly relatives, which is said to have been visited over 6.3 million times in the last year.
Mr Lloyd said: “I am immensely proud of how many more people Which? is now helping in their daily lives, and how effectively we take the views of consumers to business leaders, ministers, regulators and the media.
“By standing up to powerful organisations, with the backing of so many consumers, we have brought about changes that a few years ago would have been thought impossible.”
Peter Vicary-Smith, group chief executive, said: “Richard has been absolutely central to the success and prominence of Which? for half a decade.
“We are very grateful to him for his relentless hard work, his thought leadership and for turning a vision of what Which? could be as a consumer champion into reality. He can be rightly proud of the organisation he has done so much to develop, and we wish him well in whatever he decides to do next.”
Mr Lloyd will leave Which? on 20 May and intends to take a break over the summer before pursuing a new role.
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