Objective To compare prospectively early outcome and complications of catheter removal after robot-assisted radical prostatectomy (RARP) on the 4th or 7th day with a standardized running barbed suture technique. Introduction The time point of removing the indwelling catheter after RARP mainly depends on institute's/surgeon's preferences. Removal should be late enough to avoid urinary leakage and complications such as acute urinary retention (AUR) but early enough to avoid unnecessary catheter indwelling. Materials and methods A consecutive single-institutional series of patients underwent RARP between July 2015 and August 2017 and were entered in a prospectively maintained data base. Between July 2015 and December 2016 a cystogram was performed on 7th postoperative day (group A), thereafter the cystogram was performed on 4th postoperative day (group B). Incidence of acute urinary retention (AUR), urinary tract infections (UTI) and adverse events between the two cohorts was compared. Results 425 patients were analyzed (group A: n = 231; group B: n = 194). Both cohorts were comparable regarding demographic and oncological parameters. Watertight anastomosis was present in 84.8% in group A and in 82.5% in group B, respectively. AUR within 4 weeks after RARP occurred in 2.2% (n = 3) in A and 9.4% (n = 15) in B (p = 0.001). AUR within 72 h after catheter removal occurred in group A: 1% (n = 2) and in group B: 6.3% (n = 10) (p = 0.005). Symptomatic urinary tract infections occurred in 8.2% (n = 16) in group A and in 6.9% (n = 11) in group B. There were no differences in the rate of secondary anastomosis dehiscence. Age, BMI, prostate size, surgeon, or intraoperative bladder neck reconstruction were not correlated to the occurrence of AUR or UTI. Conclusions The removal of indwelling catheter on day 4 after a RARP with a running barbed suture shows similar anastomosis leakage rates as on the 7th postoperative day. However, AUR rates are higher for early removal. Patients scheduled for early removal should be carefully informed about the increased risk for AUR. Catheter indwelling time does not represent a risk factor for UTI.