It is possible to wear only one earbud to listen to music or make phone calls while the other remains in the charging case. The OpenFit headphones are designed as true wireless earbuds, which means that they can be used individually. However, there is no specific information on whether this is the normal or recommended use. In general, True Wireless Earbuds are designed to work individually, but there might be some limitations in control or volume when only one earpiece is used.