She started her school studies at Aylesbury School and also continued her drama and screen studies from Liverpool University with the intention of becoming a cinematographer. She was fond of deep love for films from her childhood. At first, she wanted to be a ballet dancer but then developed keen interest in acting since the age of 13 when she was diagnosed with juvenile arthritis. Claire has attended one year training course from Oxford School of Drama and completed it in the year 2007. 

Initially Claire worked as a Control Officer in Carlstadt Public School. During her Studies in Drama School, she has started performing in some incredible television roles like Easy Virtue, Top Girls, Touched and Watership Down. She did her stage debut through DNA, The Miracle and The Baby Girl, all performances at the Royal National Theatre, London. Paul Miller was the director of The Miracle.

Claire Foy stands a popular name by her outstanding performance in Little Dorrit, which is a mini-series, broadcasted on BBC. For the main role of -Amy Dorrit she bagged a nomination for  Best Heroine in RTS Television Awards in the year 2009. She has also done a remarkable job in portraying the character of Adora belle Dearheart for the TV movie Going Postal.

Claire has starred in fantasy thriller movie Season of the Witch and in Wreckers in the year 2011. She also went to appear in the BBC’s remake of Upstairs Downstairs for the character of Lady Persephone. In 2012, Claire has come with an important role of Charlotte in the partial autobiography, White Heat written by the highly applauded writer Paula Milne. Other famous television productions of Claire are: Hacks, The Night Watch, Peter Kosminsky's The Promise and Anne`BoMeyn in Wolf Hall. She has entered in a number of acclaimed theatre projects. She has played the role of as Lady Macbeth for the Tragedy play Macbeth; it was presented at the Trafalgar Studios. She has also been excellent in performing the shows Love, Love, Love, and Ding, Dong the Wicked at the Royal Court in the year 2012. Claire got into character as Queen Elizabeth II on new Netflix series. She was dressed like The Queen's dress for the royal wedding scene that was being shot.

The 1.62m height actress, Claire is married to Stephen Campbell Moore in December 2014 and gave birth to her first daughter in March 2015. She was 2 months pregnant with her first daughter when she finished the film, Wolf Hall. She has again started to act 6 months after giving birth to her child, for the film The Crown in 2016. Claire has mentioned The Promise as her most favorite role at the interview time with Channel 4 mini-series.