Purpose: The study aimed to evaluate the impact of the validated functional dexterity test and the Mini-Mental Status test on subjective functional outcomes, medical care situation, and health-related quality of life (HRQoL) after urinary diversion (UD). Patients and Methods: A total of 106 patients (n = 26 ileal conduits, n = 29 neobladders, and n = 51 ileocecal pouches) were included in this combined retrospective (n = 77) and prospective (n = 29) observational study. All patients performed the 2 tests mentioned above and filled out self-designed questionnaires with diversion and HRQoL items. In the prospective cohort, the tests were performed preoperatively and the questionnaires were filled out preoperatively as well as 3 and 6 months after surgery. Results: Reduced dexterity and cognitive skills were significantly associated with increased patient age and subjective constraints in stoma care of ileal conduits, self-catheterization in ileocecal pouches, and continence in neobladders. Overall HRQoL, however, was not affected by dexterity or cognitive measures. Conclusions: Assessing the cognitive status and functional dexterity of patients undergoing UD might provide a useful objective clinical tool to aid in decision-making regarding the type of UD and postoperative medical care situation. Further prospective data are needed to confirm these findings and further simplify the methods used here.