For Disney, she is best known for her live-action role as Mia Thermopolis in the 2001 comedy film The Princess Diaries and its 2004 sequel, The Princess Diaries 2: Royal Engagement. In March 2016, Garry Marshall confirmed that Hathaway is set to reprise her role as Mia in The Princess Diaries 3.
Hathaway's other Disney roles include her debut as Jean Sabin in the 2002 drama film The Other Side of Heaven and the White Queen in Tim Burton's 2010 live-action version of Alice in Wonderland. She also voiced Haru Yoshioka in the 2003 English dub version of Studio Ghibli's The Cat Returns, and played Ella of Frell in the 2004 Miramax family fantasy film, Ella Enchanted. She reprised her role of the White Queen in the 2016 film Alice Through the Looking Glass. She was also mentioned in the Andi Mack episode "Cyrus' Bash-Mitzvah!".