Paul Thomas Anderson (born June 26, 1970), also known by his initials PTA, is an American filmmaker. Often described as one of the preeminent filmmakers of his generation, his accolades include a BAFTA Award and nominations for eleven Academy Awards, a Golden Globe Award, and a Grammy. He is the only person to have won Best Director at the Cannes Film Festival, the Silver Lion at the Venice Film Festival, and the Silver and Golden Bear at the Berlin Film Festival.

Many of Anderson's films are psychological dramas characterized by depictions of desperate characters and explorations of dysfunctional families, alienation, loneliness, and redemption, alongside a bold visual style that uses constantly moving cameras and long takes. After his directorial debut, Hard Eight (1996), Anderson had critical and commercial success with Boogie Nights (1997), and received further accolades with Magnolia (1999) and Punch-Drunk Love (2002).

There Will Be Blood (2007), Anderson's fifth film, is regarded as one of the greatest films of the 21st century. It was followed by The Master (2012) and Inherent Vice (2014), an adaptation of the 2009 novel by Thomas Pynchon. Anderson's next two films, Phantom Thread (2017) and Licorice Pizza (2021), were both nominated for the Academy Award for Best Picture. His tenth film, One Battle After Another, was released in 2025, and became Anderson's highest-grossing film.

Anderson is noted for his collaborations with the cinematographer Robert Elswit, the costume designer Mark Bridges, the composers Jon Brion and Jonny Greenwood, and actors including Philip Seymour Hoffman, Daniel Day-Lewis, John C. Reilly, and Joaquin Phoenix. He has directed music videos for artists including Fiona Apple, Haim, Aimee Mann, Joanna Newsom, Michael Penn, Radiohead, and the Smile. He also directed a 2015 documentary about Greenwood's album Junun, and the short music film Anima (2019) for the Radiohead singer Thom Yorke.

Paul Thomas Anderson was born in Studio City, Los Angeles, on June 26, 1970, to Edwina (née Gough) and actor Ernie Anderson. His father was the voice of ABC and played a Cleveland late-night horror host known as Ghoulardi, after whom Anderson later named his production company. Anderson has three siblings and five half-siblings from his father's first marriage. He grew up in the San Fernando Valley and was raised as a Roman Catholic. He had a troubled relationship with his mother, but was close with his father, who encouraged him to become a writer or director. He attended private schools including the Buckley School, John Thomas Dye School, Campbell Hall School, Cushing Academy, and Montclair College Preparatory School.

Anderson was involved in filmmaking from an early age, and never had an alternative plan to directing films. He made his first film when he was eight years old, and started making films on a Betamax videocamera his father bought in 1982. He later started using 8 mm film, but realized that video was easier. As a teenager, he began writing and experimenting with a Bolex 16 mm camera. After years of experimenting with "standard fare", Anderson wrote and filmed his first real production as a senior at Montclair Prep, using money he earned cleaning cages at a pet store. The film was a 30-minute mockumentary about a porn star, The Dirk Diggler Story (1988), with a story inspired by John Holmes, who also inspired Boogie Nights (1997), the feature-length adaptation of The Dirk Diggler Story.

Anderson attended Santa Monica College before spending two semesters as an English major at Emerson College, where he was taught by David Foster Wallace. Anderson attended New York University for two days before he began his career as a production assistant on television, films, music videos, and game shows in Los Angeles and New York City. Feeling that film school turned the material into "homework or a chore", Anderson decided to make a 20-minute film as his "college".

On a budget of $10,000 (which came from gambling winnings, his girlfriend's credit card, and money his father had set aside for him for college), Anderson made Cigarettes & Coffee (1993), a short film connecting multiple storylines with a $20 bill. It screened at the 1993 Sundance Festival Shorts Program. He planned to expand it to feature-length, and was invited to the 1994 Sundance Feature Film Program. Michael Caton-Jones served as Anderson's mentor. He saw him as someone with "talent and a fully formed creative voice, but not much hands-on experience", and gave him some hard and practical lessons.