One of our favourite childhood actresses announced her happy news via Instagram, sharing an image of her engagement ring while holding hands with her new fiancée.
Julia – who rose to fame in teen movies including 10 Things I Hate About You and Save The Last Dance - added the simple caption: "Best Christmas Ever."
A rep for Julia, 34, later told People that her camera assistant boyfriend Preston J Cook had popped the question on Christmas Eve while they were on holiday in Colombia.
It's believed they met on the set of upcoming thriller movie Go With Me, which was filmed back in 2014.
After shooting to fame in some of our favourite teen movies, Julia returned to university to study English Literature at Columbia in New York.
Most recently, she's best known for playing Nick Parsons in the Jason Bourne movies.
Congrats to Julia and Preston!