Rathbone enjoys music, writing, singing dan producing.[7] He performs in a band called 100 Monkeys with two friends whom he met in high school at Interlochen Arts Academy, Ben Graupner dan Ben Johnson[8] as well as close friends Jerad Anderson dan M. Lawrence Abrams aka Uncle Larry.[petikan diperlukan][18] The band released three albums in 2009.[19] In December 2009, 100 Monkeys began a 100-city tour that will take them to nearly every state in the US by mid-2010.[petikan diperlukan] The band continues to tour into 2011 to coincide with the release of their new album, due out in January.[20] Rathbone resides in Los Angeles.

Beliau adalah kawan karib dengan rakan selakon Twilight, terutamanya Ashley Greene dan Kellan Lutz.[21]