On the stage, Fiennes' 2023 portrayal of Gareth Southgate in James Graham's Dear England earnt him a nomination for a Laurence Olivier Award for Best Actor.

His nephew Hero Fiennes Tiffin played Tom Riddle, young Lord Voldemort in Harry Potter and the Half-Blood Prince.

In 2003, he lent his voice as Proteus in the DreamWorks animated film Sinbad: Legend of the Seven Seas opposite Brad Pitt.

Fiennes returned to the theatre in 2006 to perform in the one-man play Unicorns, Almost about World War II poet Keith Douglas at the Old Vic.

Fiennes starred in the ABC science fiction series FlashForward, which debuted on 24 September 2009 and ran through 27 May 2010, as Mark Benford.

[13] In the second season of American Horror Story, which premiered in October 2012, Fiennes played the role of Monsignor Timothy Howard.

In August 2009 Fiennes married María Dolores Diéguez, a Swiss model of Spanish/Galician origin, in a Roman Catholic ceremony in Tuscany.

[15][16] Fiennes was one of the celebrities to design and sign his own card for the UK-based charity Thomas Coram Foundation for Children.