We appraised life satisfaction using the Satisfaction with Life Scale (SWLS), and analysed its psychometric properties in persons with intellectual disability (ID). Ninety-nine persons with ID from four services in Spain participated. A battery of subjective assessments was used, including the SWLS, a Quality of Life measure (WHOQOL-BREF), and health status and sociodemographic information. Psychometric properties of the SWLS were investigated using standard psychometric methods. Overall, our results showed that persons with ID were satisfied with their life (SWLS score 25–29). Internal consistency (Cronbach's alpha) was .79. A factor analysis using principal components method, showed a one factor structure accounting for 55.7% of the variance. Associations, using Spearman's rho correlation coefficients, were confirmed between SWLS with the overall QoL, satisfaction with health and WHOQOL-BREF total score. Regarding ‘known group’ differences, persons living in residential institutions had lower life satisfaction compared to persons living in community facilities or living at home, though differences were not statistically significant. Student t-tests showed that SWLS scores significantly discriminated between healthy and unhealthy; and those reporting higher satisfaction with their relationships, home environment and their jobs compared to participants with lower satisfaction levels. To our best knowledge, this study is the first to report on the psychometrics properties of the SWLS in persons with ID, both in Spain and internationally. It might be a promising tool to use, with other outcome measures, in appraising persons with ID in different services and types of care; also, it might guide policymakers on the implementation of policies for persons with ID.