Harmonicity is an organizing principle in the auditory system, facilitating auditory object formation. The goal of the current study is to determine if harmonicity also facilitates binaural fusion. Participants listened to pairs of two-tone harmonic complex tones that were harmonically or inharmonically related to each other. When the components of two inharmonically related complex tones were divided between the ears, the resulting percept was not binaurally fused. In contrast, when the components of two harmonically related complex tones were divided between the ears, binaural fusion occurred, even absent interaural spectral overlap. This suggests that harmonicity can facilitate binaural fusion.