Evidence suggests that adolescent males take part in more moderate-to-vigorous physical activity (MVPA) than females, and that adolescents with disabilities participate in even less. Public health data are typically based on the international physical activity (PA) recommendations of at least 60 minutes of MVPA daily. However, it appears that data are lost because a person who reports MVPA 0-6 days a week is grouped together and is considered as 'inactive'. Therefore, the purposes of this study were to report differences among adolescents with and without disabilities who were 'active' and 'inactive' and to explore differences by sex. A complete enumeration study (2017 School Health Promotion Survey; n = 128,803) of Finnish adolescents aged between 14-19 years old was conducted. The single item self-report MVPA was used with items from the Washington Group on Disability Statistics. Data were grouped into physiological and cognitive disabilities and were split into active and inactive adolescents based on the PA recommendations; subsequently, binary logistic regression analyses were performed. Data from the inactive participants were analyzed with multivariate analysis of covariance and effect sizes were reported. Approximately 10% of males and 17% of females reported disabilities. There were fewer adolescents with disabilities who took part in daily PA (OR = 0.90, CI = 0.85-0.94), especially among those with cognitive disabilities (OR = 0.86, CI = 0.82-0.91). There were more active male than female adolescents (OR = 1.48, CI = 1.43-1.52). Of the inactive adolescents, females reported similar MVPA to males, with and without disabilities after controlling for age, school type, and family financial situation. Inactive adolescents with walking difficulties reported the least amount of MVPA (males; mean = 2.24, CI = 2.03-2.44, females; mean = 2.18, CI = 1.99-2.37). The difference in means with adolescents without disabilities according to Cohen's d effect size was medium for males (0.56) and females (0.58). The effect sizes from all other groups of disabilities were small. The difference in PA between males and females has diminished among the inactive groups, yet there is still a need to improve the gap between males and females, especially for those who meet the PA recommendations. More strategies are needed to improve MVPA among adolescents with disabilities, especially those with cognitive disabilities.