Moderate-to-vigorous physical activity (MVPA) during childhood is vital for development. Youth with intellectual disabilities (ID) are suggested to be less active, and no measure of intensity and time spent in MVPA has been made outside school. The purpose of this study was to determine the feasibility of monitoring contextual characteristics (CC) of PA of youth with ID over 7-days using Telephone Time Diaries (TTD). Three children with mild ID participated in this study which analyzed PA time spent in different intensity levels and settings. Objective PA was gathered using ActiGraph GT1M accelerometers, subjective PA with TTD.Data showed mean weekend MVPA > weekdays. TTD were found feasible for monitoring CC of PA of children with ID.