She was joined by Prince Philip, and the couple have stayed at the estate for the majority of lockdown.
Prince Philip is now back at his main residence, Wood Farm at the Queen’s Sandringham Estate.
The Queen will continue to live at Windsor Castle but will occasionally stay at Buckingham Palace for royal duties.
A statement from Buckingham Palace published on October 1 read: “In line with current government guidelines, and as a sensible precaution in the current circumstances, there will be no large scale events held at Buckingham Palace or Windsor Castle for the rest of this year.