BACKGROUND AND AIMS: High migration rates for fully covered self-expanding metal stents (FC-SEMSs) have been reported in the literature. Endoscopic suture fixation has been explored as a mitigation strategy. We aimed to compare rates of migration and other adverse events after esophageal FC-SEMS placement with and without endoscopic suturing. METHODS: We performed a randomized controlled trial involving adult patients who underwent FC-SEMS placement at our institution for management of esophageal strictures (ClinicalTrials.gov: NCT05082948). Patients were randomly allocated (1:1 stratified randomization based on benign or malignant etiology) to FC-SEMS placement with endoscopic suture fixation or FC-SEMS placement alone. All investigators were blinded to the randomization sequence. Patients and statistical analysts were blinded to intervention assignment. Primary outcome was stent migration, and secondary outcomes were other stent-related adverse events, technical success, procedure duration, time to migration, premature stent removal due to adverse events. Additionally, we performed a cost-effectiveness analysis (CEA) comparing endoscopic suturing with FC-SEMS placement alone. RESULTS: Between July 2021 and December 2022, 46 patients were enrolled - 24 in the fixation group and 22 in the non-fixation group. In intention-to-treat analysis, stent migration rate was significantly lower in the fixation group compared to the non-fixation group (Risk ratio, 0.28, 95% CI, 0.11-0.74, p = 0.008). All secondary outcomes were similar in both groups, except procedure duration, which was longer in the fixation group (p = 0.002). Endoscopic suturing was cost-effective for preventing stent migration compared to stent placement alone. The trial was terminated early after interim analysis clearly showed inferior primary outcomes in the non-fixation group. CONCLUSIONS: These findings support the efficacy, safety, and cost-effectiveness of endoscopic suture fixation for preventing esophageal FC-SEMS migration. Further studies comparing endoscopic suturing and other stent fixation strategies are warranted.