This study evaluated the efficacy of an 8-week (two sessions/week; 60 min/session) adapted soccer intervention on skill performance and retention in 30 adults (18 men and 12 women) ages 17-40 years with autism spectrum disorder, Down syndrome, and intellectual disability. Of these 30 participants, 18 completed a 1-month retention test. The program included behavior supports and adaptations for participants with varying levels of behavioral needs. Dribbling, kicking a moving ball, kicking a stationary ball, throw-ins, trapping, and a composite skill score were examined. Linear mixed-effect regression revealed a significant time main effect with improvements from pretest to posttest and pretest to retention for all skills. In addition, modest offline gains (i.e., posttest < retention) were observed for throw-ins, kicking a moving ball, and the composite skill score. A significant main effect of diagnosis was observed such that participants with autism spectrum disorder had better performance on kicking a moving ball than those with Down syndrome and intellectual disability. Finally, a significant main effect of level of function was observed. This program enabled adults with various disabilities to acquire fundamental soccer skills that may lead to meaningful participation in community soccer programs.