Born in Swansea, Joanna Page attended her local comprehensive school, before graduating from RADA in 1998. She then spent ten years in stage-based roles for the Royal National Theatre and Royal Shakespeare Company. She also secured roles in major films, such as From Hell, Mine All Mine, Nativity 2: Danger in the Manger and Richard Curtis' classic, Love Actually.

Joanna came to wider public attention after taking a leading role in the BBC comedy Gavin & Stacey, playing the main part of Stacey Shipman. She appeared in the show's three series between 2007 and 2010, before returning for a Christmas special in 2019 and the last ever episode, which aired on Christmas Day 2024 and was watched by over 20 million viewers - making it the UK's most-watched scripted show since records began.

Joanna can be found now on TV as a presenter, most recently as the host of Joanna Page's Wild Life for the BBC. Otherwise, she can be found at home with her husband, fellow actor James Thornton, and their four children, two dogs, and four guinea pigs.