King, who joined the company at the start of January 2009, will be replaced by the group’s chief operating officer and president of Time Out New York, Aksel van der Wal.
Before joining Time Out last year, van der Wal was chief finance officer of Seatwave and prior to that, CFO of Vodafone’s Global Business Development unit.
The private company declined to provide any detailed update regarding its financial position, but did stress "UK digital revenues are up 71% year on year for June and unique users hit a record 4.1 million".
In a statement, King said: "Time Out has been restructured, refinanced, moved back into profit, reintegrated with the US sister company, and is delivering strong traffic and digital revenue growth.
"The business is stable, has a good team in place and now is the right time to handover as the business moves into a delivery and growth phase, rolling out its new online and mobile digital services in the UK, US and across the licensee network."
Time Out Group founder Tony Elliott called King a "highly trusted and effective CEO", and credited him for having "successfully led Time Out through one of the most difficult periods in its history".
King's departure follows the recent announcement of three key appointments to strengthen the Time Out e-commerce and transactions team, in a drive to develop their knowledge business into a more transactional one.
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