Tamzin Claire Merchant was born in the UK (Sussex), in 4 March 1987 but spent part of her childhood in Dubai. She attended Windlesham School and Brighton College, and had been planning to study at Nottingham University, when she was cast in Pride and Prejudice (2005) a year before finishing her A-levels.
After twice deferring university places to concentrate on her acting career, she was a student at Homerton College, Cambridge.
Tamzin has written several poems, including "Where Does Revenge Stop?" and "Ode to a Toilet", for Platforms Magazine.
Tamzin is a patron of the international development charity Build Africa.
Tamzin is most known for her role as Katherine Howard in The Tudors and for her role as Georgiana Darcy.