[16] Some of Chabert's earliest roles were in television commercials for Burger King, Triaminic Cough Syrup, Zest and Secret Beauties dolls.

The show centered on the five Salinger siblings, who are orphaned after their parents are killed in a car accident caused by a drunk driver.

[19][20] She won The Hollywood Reporter's annual YoungStar Award for Best Performance by a Young Actress in a Drama TV Series in both 1997 and 1998 for Party of Five, and was nominated three other times for her work in 1999 to 2000.

She then had a supporting role as Amanda Becker in the parody film Not Another Teen Movie (2001), and provided the voice of Aleu, the title character's daughter, in Balto 2: Wolf Quest (2002).

She and her co-stars Lindsay Lohan, Rachel McAdams and Amanda Seyfried went on to win the 2005 MTV Movie Award for "Best On-Screen Team".

Chabert also played the title role in The Brooke Ellison Story, a 2004 television biopic produced and directed by Christopher Reeve, based on a real-life quadriplegic woman who overcame obstacles to graduate from Harvard University.

Chabert then appeared in Hello Sister, Goodbye Life (2006) on ABC Family; had a role in a 2006 remake of the 1974 horror film Black Christmas, and in an episode of Ghost Whisperer opposite former Party of Five co-star Jennifer Love Hewitt.

Her voice work in the second half of the decade included the roles of Princess Elise in the video game Sonic the Hedgehog and Gwen Stacy in The Spectacular Spider-Man animated series.

[22] In 2015, she starred in the television film A Christmas Melody alongside Mariah Carey, Brennan Elliott, Kathy Najimy and Fina Strazza.

[30] In February 2022, Chabert signed an exclusive multi-film deal with Hallmark Channel's parent company, Crown Media Family Networks.

[31] In November 2023, Chabert starred in a Mean Girls-themed Black Friday commercial for Walmart, along with her original co-stars Lindsay Lohan, Amanda Seyfried, Rajiv Surendra and Daniel Franzese.

[40][41] Chabert wrote about discovering that she was pregnant, learning that she was having a girl, and figuring out smart ways to hide her baby bump on film sets.