BACKGROUND: The purpose of this study was to assess patient frailty as a risk factor for radical cystectomy (RC) complications. MATERIALS AND METHODS: We performed an analysis of prospectively collected data of consecutive patients 80 years of age or older who underwent RC and ureterocutaneostomy in 6 primary care European urology centers. Frailty was measured using a simplified frailty index (sFI) with a 5-item score including: (1) diabetes mellitus; (2) functional status; (3) chronic obstructive pulmonary disease; (4) congestive cardiac failure; and (5) hypertension, with a maximum 5-item score meaning high level of frailty. Within 90 days surgical complications were scored according to the Clavien Classification System (CCS). sFI >/=3 was considered as poor frailty status. Clinical and pathological variables were analyzed as predictors of severe complications (CCS >/=3). RESULTS: One hundred seventeen patients were enrolled. Most patients reported an sFI score of 2 and 3, respectively, 31/117 (26.5%) and 45/117 patients (38.5%). CCS >/=3 occurred in 17/117 patients (14.5%). Patients with sFI >/=3 were significantly older than patients with sFI /=3 scores occurred in patients with sFI >/=3: 13 (11.1%) versus 4 (3.4%; P = .02). No significative differences were detected in terms of length of hospital stay, pathological stage, and postoperative bowel canalization when related to sFI. sFI >/=3 was an independent risk factor of CCS >/=3 in univariate and multivariate analysis (respectively, odds ratio [OR], 3.81 [95% confidence interval (CI), 1.16-12.5; P = .02] and OR, 3.1 [95% CI, 0.7-13.7; P = .01]). Body mass index, age, American Society of Anesthesiologists score >/=3, and pathological stage were not related to CCS >/=3. CONCLUSION: RC appears feasible in elderly patients with an sFI /=3, this choice should be carefully valued, discussed, and possibly avoided because of a higher risk of complications.