In 2007, Bell ended a five-year relationship with former fiancé Kevin Mann. She later told Complex magazine that dating “makes me want to vomit. And not out of grossness — OK, a little bit out of grossness, but just nerves.” Bell explains, “I’ve always been a serial monogamist.”
Bell began dating actor Dax Shepard in late 2007. The couple announced their engagement in January 2010,and later co-starred in the 2012 film Hit and Run. However, they have decided to delay marriage until the state of California passes legislation legalizing same-sex marriage. In November 2012, the couple announced that they are expecting their first child.