Background: The purpose of the present study was to add to the literature on the predictive accuracy of a dynamic intellectual disability specific risk assessment tool. Method: A dynamic risk assessment for sexual reoffending (ARMIDILO-S), a static risk assessment for sexual offending (STATIC-99), and a static risk assessment for violence (Violence Risk Appraisal Guide [VRAG]) were completed for a sample of 64 adult males with an intellectual disability. Results: The dynamic risk assessment for sexual offenders with an intellectual disability resulted in the best prediction of sexual reoffending (ARMIDILO-S area under the curve (AUC) = 0.92) this was better than an established sexual offending static risk assessment (STATIC-99 AUC = 0.75). A static tool for violent reoffending, did not perform as well in this group (VRAG AUC = 0.58). Conclusions: Results suggest that dynamic variables are useful in predicting sexual reoffending with individuals with an intellectual disability, confirming previous findings. The ARMIDILO-S is a promising dynamic risk assessment for individuals with an intellectual disability.