Captain Tom Moore, who raised more than £29m for the NHS by walking laps of his garden, has been made an honorary colonel on his 100th birthday, the BBC reports.
The war veteran will mark the occasion with thousands of birthday cards, including one from the Queen.
He said it was “extraordinary” to be turning 100, especially with “this many well-wishers”.
Head of the Army General Sir Mark Carleton-Smith called Capt Tom “an inspirational role model”.
Capt Tom is due to spend the majority of the day self-isolating with his daughter Hannah Ingram-Moore and her family at his home in Marston Moretaine, Bedfordshire.
He said he would also speak to other family members via the internet.
As well as receiving a personalized card from the Queen, Capt Tom will be made an honorary England cricketer by former captain Michael Vaughan.