Toni Collette Galafassi (born Toni Collett; 1 November 1972) is an Australian actress, producer, singer, and songwriter. Known for her work in television and independent films, she has received various accolades throughout her career, including a Golden Globe Award, a Primetime Emmy Award, and five AACTA Awards, in addition to nominations for an Academy Award, a Tony Award, and two BAFTA Awards.

Collette made her film debut in the 1992 film Spotswood. Her breakthrough role came in the comedy drama Muriel's Wedding (1994), which earned her a Golden Globe Award nomination and won her the AACTA Award for Best Actress in a Leading Role. Collette received further acclaim for her role in the thriller The Sixth Sense (1999) for which she received a nomination for the Academy Award for Best Supporting Actress. She received BAFTA Award nominations for her performances in the romantic comedy About a Boy (2002) and the comedy drama Little Miss Sunshine (2006). Collette's other films include Emma (1996), Velvet Goldmine (1998), The Hours (2002), Japanese Story (2003), In Her Shoes (2005), The Way, Way Back (2013), Krampus (2015), Hereditary (2018), Knives Out (2019), I'm Thinking of Ending Things (2020), and Nightmare Alley (2021).

In television, she starred in the Showtime comedy-drama series United States of Tara (2008–2011) earning the Primetime Emmy Award for Outstanding Actress in a Comedy Series. Other Emmy-nominated roles include the Netflix miniseries Unbelievable (2019), and the HBO limited series The Staircase (2022). She made her Broadway debut in The Wild Party (2000), earning a Tony Award for Best Actress in a Musical nomination.

Collette married Dave Galafassi, drummer of the band Gelbison, in January 2003. The couple have two children together. As the lead singer of Toni Collette & the Finish, she wrote all 11 tracks of their sole album, Beautiful Awkward Pictures (2006). The band toured Australia, but have not performed nor released any new material after 2007. Collette and Jen Turner co-founded the film production company Vocab Films in 2017.