The Queen has flown by helicopter from Windsor Castle to Sandringham where she is expected to spend the next few weeks.
The monarch normally hosts her family at the Norfolk estate during the festive period, with the royals attending church together on 25 December.
But the Queen, 95, decided earlier in December to remain at Windsor as a precautionary measure following rising COVID-19 cases at the time.
Prior to Christmas Day a Clarence House spokesman said the Queen would spend 25 December with the Prince of Wales and the Duchess of Cornwall.
On 6 February, Her Majesty will mark the historic milestone of 70 years on the throne, heralding the start of Platinum Jubilee celebrations.
Last month was the Queen’s first Christmas period without the Duke of Edinburgh, her husband of more than 73 years, who died on 9 April last year.
There were concerns for the Queen’s health during autumn last year after she pulled out of a number of major engagements, spent a night in hospital and was ordered to rest by doctors.
The Queen was advised to carry out light duties but also sprained her back, leading to her missing the Remembrance Sunday service.