[3] She attended Jericho High School[4] and studied at the Cultural Arts Playhouse in Old Bethpage, New York.

[7][8] Sigler played the title role in Cinderella on tour and at The Theatre at Madison Square Garden in 2001.

In 2005, Sigler starred in Love Wrecked and the following year in Homie Spumoni, when she played the role of Alli, the girlfriend of Renato/Leroy (Donald Faison) directed by Mike Cerron.

In the fifth season, she appeared as the love interest of the character Sal 'Turtle' Assante, portrayed by Jerry Ferrara.

[13] On November 17, 2008, Sigler guest-starred as Jillian on the TV series How I Met Your Mother in the episode "Woooo!".

[14] On the December 6, 2008, airing of Saturday Night Live, she appeared as the checkout girl for the Digital Short music video "Jizz in My Pants" by The Lonely Island.

[15] In 2009, Sigler starred in the psychological thriller film Beneath the Dark, which originally had a working title of Wake.

[18] In 2020, Sigler starred as a featured player in the Adult Swim sitcom Beef House.

[19] In 2001, Sigler released a pop album called Here to Heaven, which featured the single "Cry Baby."

[38][39] In 2023, Novartis hired Sigler to star in a TV commercial for their multiple sclerosis drug Kesimpta.