He is currently living in Beverly Hills, California. In August 2011, his brother Joel said on an Australian radio interview that Benji was genuinely looking for an Australian property he can call home.

In January 2008, media outlets reported that Madden and his long-time fiancée, Australian starlet Sophie Monk, had split up. In response to the rumors, Good Charlotte’s rep told Us Weekly: “Benji Madden and Sophie Monk are together and very happy.” However, in mid-February it was officially announced by Monk’s Sydney agent, that “Sophie and Benji have officially split. The decision was mutual and they remain amicable.” Madden then dated Paris Hilton from February to November 2008. Madden also dated television personality Holly Madison, from December 2009 until January 2010. However they have remained very close friends.

Madden is an avid collector of Living Dead Dolls. In an episode of MTV Cribs he showed off his vast collection. He is known for having many tattoos, including a tattoo of Ben Franklin, which covers his entire back.