The annual festive broadcast was watched by an average of 8.1 million viewers on BBC One, the broadcaster has confirmed.
Charles’s address to the nation was a personal reflection on the year, touching on current issues and with a Christian framework.
He sympathised with families struggling with the cost of living and spoke about the “great anxiety and hardship” experienced by many trying to “pay their bills and keep their families fed and warm”.
Charles delivered his historic Christmas broadcast standing in the quire of St George’s Chapel, mirroring the late Queen’s 1999 festive address, and it followed his mother’s well-established template, a personal reflection on the year, touching on current issues and with a Christian framework.
The Christmas Day ratings were confirmed as it was revealed the TV adaptation of Charlie Mackesy’s bestselling illustrated book The Boy, The Mole, The Fox And The Horse was the most watched BBC programme on Christmas Eve.
An average of four million people tuned in to watch the author and illustrator’s distinctive images reimagined with hand-drawn traditional animations for the BBC One short film about kindness, friendship, courage and hope.
The film enlisted Hollywood star Idris Elba as the voice of the fox, and Tom Hollander, whose credits include The Night Manager and Bohemian Rhapsody, as the mole.
Veteran Irish actor Gabriel Byrne featured as the horse and newcomer Jude Coward Nicoll was the boy.
The short film was produced by Star Wars director JJ Abrams and Hannah Minghella of Bad Robot Productions, with an original score by composer Isobel Waller-Bridge, sister of Fleabag star Phoebe.
The Boy, The Mole, The Fox And The Horse was published in 2019. The illustrated book explores the friendship between the four titular characters as they journey together in search of a home.
After its publication, it was named book of the year by Waterstones and was shortlisted for the British Book Awards’ non-fiction lifestyle book of the year.
Mackesy, 59, previously worked with Nelson Mandela on a lithograph project, The Unity Series, and also helps support a honey social enterprise in Zambia.
His latest exhibition based on the book features about 60 original artworks in ink and paint for sale alongside the floor-to-ceiling murals at Sotheby’s cafe.