Hilton is the oldest of four children of Richard Hilton and Kathy Richards. Her younger sister is Nicky Hilton (after paternal great-uncle, Conrad Nicholson Hilton II, 'Nicky'), and her younger brothers are Barron Hilton II (after paternal grandfather Barron Hilton), and Conrad Hilton III (after paternal great-grandfather Conrad Nicholson Hilton I).

On the maternal side of her family, Hilton is a niece of two popular child stars of the 1970s—Kim Richards and Kyle Richards, who appeared in the motion picture Escape to Witch Mountain and TV shows such as Nanny and the Professor, Little House on the Prairie, and later, ER. By marriage, she also is related to Zsa Zsa Gabor (the Hungarian-born actress married Paris Hilton's great-grandfather Conrad Hilton), as well as Elizabeth Taylor (the actress's first husband was Paris Hilton's great-uncle, Conrad Nicholson Hilton Jr.).

Her paternal grandparents are hotel chairman Barron Hilton, and his wife, the former Marilyn Hawley; and Hilton's paternal great-grandparents were Hilton Hotel founder Conrad Hilton and his first wife, Mary Barron. When Conrad Hilton died in 1979, he left nothing in his will to his children or other descendants. Barron Hilton contested this decision and won in 1988. The value of Paris's inheritance has been variously estimated at between (US) $30 and $50 million.

 

Hilton moved between several exclusive homes in her youth, including a suite in the Waldorf-Astoria Hotel in Manhattan, Beverly Hills, and the Hamptons. Currently, her parents own a $30.5 million mansion in Bel Air, a $12.3 million estate in the Hamptons, and a $10 million house in the Hollywood Hills in which she and her sister stay to give them privacy. She attended her freshman year of high school in Rancho Mirage, California at the Marywood-Palm Valley School and her sophomore and junior years of high school at the Dwight School in New York, but dropped out and eventually earned a GED. Hilton did not attend college.