Prime Minister David Cameron will lead tributes in the House of Commons and there will be a River Thames salute.
The exact moment the Queen reaches the milestone is not known because her father, George VI, passed away in the early hours of February 6, 1952.
On the Thames, a flotilla of historic vessels, leisure cruisers and passenger boats will take part in a procession between Tower Bridge and the Houses of Parliament. The bridge will lift as a sign of respect and H.M.S Belfast will sound a four-gun salute.
The BT Tower in central London will scroll the message “long may she reign”. She has let it be known that she does not want a fuss to be made. It is evidently viewed as bad form for one long-lived queen to be celebrating the passing of a record set by another long-lived queen.
The prime minister’s official spokeswoman said David Cameron had paid tribute to the Queen at a cabinet meeting on Monday. He said the Queen had a “remarkable record” and was “a symbol of Britain’s enduring spirit admired around the world”. Queen Elizabeth’s reign has included 12 prime ministers, two more than served under Victoria.