Kensington Palace said in a statement:
His Royal Highness The Duke of Cambridge is to leave operational service in the Armed Forces.
He completes his Tour with the Royal Air Force Search and Rescue Force at RAF Valley, Anglesey, after more than seven-and-a-half years of full-time military service.
He will continue to support the work of the Queen and the Royal Family through a programme of official engagements, both at home and overseas, with The Duchess of Cambridge.
The Duke will work closely over the next 12 months with the Royal Foundation of The Duke and Duchess of Cambridge and Prince Harry.
He will expand his work in the field of conservation, particularly in respect of endangered species.
The Duke will continue to work with his charities on issues relating to children and young people, veterans and serving members of the Armed Forces.
The Duke is currently considering a number of options for public service, a further announcement on which will follow in due course.
The Duke and Duchess of Cambridge and Prince George are expected to move into their official residence at Kensington Palace within the next few weeks.
More top news
The Duke of Cambridge followed in his mother's footsteps today as he visited Commonwealth War Graves in Japan.
Arsenal legend Thierry Henry says it would be a dream to manage the club one day, but admits he's got to learn his trade first.
Across most of England and Wales it will be a clear, chilly night and Friday morning will start off cold but bright until cloud builds up.