It will be the first time since 1988 that Her Majesty, 94, and the Duke of Edinburgh, 99, have not celebrated in Norfolk. Some of the Royal Family may join them in the castle grounds but there will be no big gathering and it is likely they will have their Christmas Day meal without other relatives.
The Queen, who is Supreme Governor of the Church of England, has also decided she will not attend church on Christmas Day to avoid the risk of attracting crowds and spreading coronavirus.
A Buckingham Palace spokeswoman said: “Having considered all of the appropriate advice, the Queen and the Duke of Edinburgh have decided that this year they will spend Christmas quietly in Windsor.”
Prince Charles and the Duchess of Cornwall will spend Christmas Day at Highgrove, their country retreat near Tetbury in Gloucestershire, but intend to see the Queen and Philip at some point.
Camilla, 73, will also see her family but the meetings may be socially distanced and outside because of government rules restricting each family to a Christmas bubble of no more than three households that cannot be swapped between December 23 and 27.
It is not clear yet how the Duke and Duchess of Cambridge and their children will spend Christmas.
The Queen and Philip’s decision surprised friends who thought they would want to follow the tradition of moving the court to Sandringham for the winter, just as they went to their Scottish retreat Balmoral in the summer.
They were presented with an option to do that and a plan to overcome a staff revolt at Sandringham – where key workers had refused to commit to isolating from their own families so that they could work for the Queen during her stay there.
But after considering the various options they decided to remain in Berkshire.
It was their private decision and they did not consult Prime Minister Boris Johnson or his ministers.
The Queen, who was photographed horse riding in Windsor yesterday, has spent much of this year at the 950-year-old royal fortress.