IMPORTANCENo data exist on time to recovery of patient-reported and performance-related measures of functional independence after radical cystectomy (open or robotic). OBJECTIVE To determine recovery of functional independence after radical cystectomy and whether robot-assisted radical cystectomy (RARC) is associated with any advantage over open procedures. DESIGN, SETTING, AND PARTICIPANTS Data for this secondary analysis from the RAZOR (Randomized Open vs Robotic Cystectomy) trial were used. RAZOR was a phase 3 multicenter noninferiority trial across 15 academic medical centers in the US from July 1, 2011, to November 18, 2014, with a median follow-up of 2 years. Participants included the per-protocol population (n = 302). Data were analyzed from February 1, 2017, to May 1, 2021. INTERVENTIONS Robot-assisted radical cystectomy or open radical cystectomy (ORC). MAIN OUTCOMES AND MEASURES Patient-reported (activities of daily living [ADL] and independent ADL [iADL]) and performance-related (hand grip strength [HGS] and Timed Up & Go walking test [TUGWT]) measures of independence were assessed. Patterns of postoperative recovery for the entire cohort and comparisons between RARC and ORC were performed. Exploratory analyses to assess measures of independence across diversion type and to determine whether baseline impairments were associated with 90-day complications or 1-year mortality were performed. FINDINGS Of the 302 patients included in the analysis (254 men [84.1%]; mean [SD] age at consent, 68.0 [9.7] years), 150 underwent RARC and 152 underwent ORC. Baseline characteristics were similar in both groups. For the entire cohort, ADL, iADL, and TUGWT recovered to baseline by 3 postoperative months, whereas HGS recovered by 6 months. There was no difference between RARC and ORC for ADL, iADL, TUGWT, or HGS scores at any time. Activities of daily living recovered 1 month after RARC (mean estimated score, 7.7 [95% CI, 7.3-8.0]) vs 3 months after ORC (mean estimated score, 7.5 [95% CI, 7.2-7.8]). Hand grip strength recovered by 3 months after RARC (mean estimated HGS, 29.0 [95% CI, 26.3-31.7] kg) vs 6 months after ORC (mean estimated HGS, 31.2 [95% CI,] kg). In the RARC group, 32 of 90 patients (35.6%) showed a recovery in HGS at 3 months vs 32 of 88 (36.4%) in the ORC group (P = .91), indicating a rejection of the primary study hypothesis for HGS. Independent ADL and TUGWT recovered in 3 months for both approaches. Hand grip strength showed earlier recovery in patients undergoing continent urinary diversion (mean HGS at 3 months, 31.3 [95% CI,] vs 33.9 [95% CI, 30.5-37.3] at baseline; P = .09) than (continued) Key Points Question Is robot-assisted radical cystectomy (RARC) associated with faster recovery of patient-reported and performance-related measures of independence when compared with open radical cystectomy (ORC)? Findings This secondary analysis of the RAZOR (Randomized Open vs Robotic Cystectomy) trial found that patients require 3 to 6 months to recover baseline levels of independence irrespective of su...