Individuals with serious mental illness (SMI) often experience isolation and poor health, but normalized social opportunities aid recovery. This study aimed to determine social dance's feasibility and effects on mood, functional mobility, and balance confidence in 12 people with SMI. Participants danced once per week in 1-hour lessons for 10 weeks. Before and after lessons, participants were evaluated for gait velocity and with one-leg stance, Timed Up and Go, and 6-minute walk tests. Participants self-completed Beck Depression II and Beck Anxiety Inventories and the Activities-specific Balance Confidence Scale. Posttesting included an exit questionnaire assessing participant experiences. Participants significantly improved on the Timed Up and Go, (p = 0.012, effect size = 0.68), and demonstrated nonsignificant improvements in anxiety, depression, and balance confidence (effect sizes of 0.41, 0.54, and 0.64, respectively). Participants reported enjoying classes, and interest to continue. Social dance is feasible and may benefit mobility for those with SMI.