He trained at the National Youth Theatre in London. He appeared in the British television series Doctors as Holden, Casualty as Johnny Cullin and Afterlife as Darren.
Westwick fronted the British indie rock band The Filthy Youth, composed of himself, Benjamin Lewis Allingham, Jimmy Wright, Mitch Cox and John Vooght. While he is now inactive in the band, largely because he wants to focus on his acting career and the other band members are still based in the UK, he has expressed an interest in forming another group in New York.
Westwick became the new face of K-Swiss.
He has guest starred in the third season of Californication as a student who is fascinated with vampire literature.
Ed was dating his Gossip Girl co-star, Jessica Szohr from late 2008. They split in May 2010.