Hilton was engaged to fashion model Jason Shaw from mid-2002 to early 2003. In 2003–2004 she had a relationship with singer Nick Carter. Later she was engaged to Greek shipping heir Paris Latsis, from May 29, 2005, to November 2005. Thereafter, she began dating another Greek shipping heir, Stavros Niarchos III, before breaking up in May 2006. In early 2008, she was spotted with Good Charlotte guitarist Benji Madden and in May, Hilton announced her intention to marry Madden during an interview with television talk-show host David Letterman. The two broke up in November 2008, and "remain very good friends". She began dating The Hills star Doug Reinhardt in February 2009; Hilton has also referred to her intention to marry Reinhardt, saying "He's gonna be my husband." The couple broke up in June 2009, only to get back together again in August of the same year. On April 13, 2010, Hilton reportedly split from Reinhardt because she was worried he was just using her to further his career. Shortly after splitting from Reinhardt, Hilton started dating Cy Waits, entrepreneur and co-owner of Tryst Nightclub and XS Nightclub in Las Vegas.Hilton expressed that she would like to marry Waits, stating: "“I can see myself marrying him. We are so happy!”. In late June 2011, Hilton revealed that the couple had split up and remained close friends.

Between March and May 2012, Paris Hilton was in a relationship with Dutch DJ Afrojack, a relationship that Afrojack told he ended as he was not ready to be in a steady relationship with Hilton. Hilton and Afrojack's publicists both denied afterwards that the two were ever dating in the first place.

Hilton gained significant notoriety for a sex tape, which was released in November 2003, shortly before the premiere of the television reality series The Simple Life alongside fellow socialite and childhood best friend Nicole Richie. The show was a massive hit for the FOX network, premiering with 13 million viewers, and brought Hilton and co-star Richie to an international recognition.