Introduction: The primary aim of this study was to compare the objective and subjective outcomes and short-term complication rates of an adjustable single-incision mini-sling (SIMS) vs. standard mid-urethral slings (SMUS). The secondary aim was to report pain perception and complications at the one-year follow up. Material and methods: The study was designed as a multicenter prospective randomized trial where women were included from eight centers in Denmark, Norway and Sweden. The trial was registered at ClinicalTrials.gov: NCT01754558. A total of 305 women less than 60 years old with verified stress urinary incontinence were included. All women were randomized to SIMS (Ajust®; n = 155) or SMUS (TVT, TVT-O or TOT; n = 150) and were evaluated by stress test and bladder diary before and after surgery and symptoms related to incontinence using ICIQ-SF, PISQ-12 and PGI-S and PGI-I. Objective cure was defined as no leakage during a stress test and subjective cure defined as no leakage stated in the bladder diary or no indication of urinary leakage in the ICIQ-SF. Furthermore, mesh exposure and dyspareunia were recorded. Results: In total, 280 women [141 (91%) in the SIMS and 139 (94%) in the SMUS groups] participated in the one-year follow up. No difference between the groups was observed regarding objective and subjective outcomes. VAS score disclosed a lower postoperative pain perception in the SIMS group than in the SMUS group. Conclusions: Ajust® appears to be as efficient as SMUS regarding objective and subjective outcomes and was associated with less pain perception during the postoperative period.