Background In a proportion of patients with an endovascular abdominal aortic aneurysm repair (EVAR), aortic cuffs or iliac graft limb extensions are required to enhance scaling or to fix the position of the device. This requirement arises when these goals are not primarily obtained with the basic stent-graft configuration. The aim of this study was to assess the influence of the use of endograft extensions during the primary EVAR procedure on the short- and long-term outcome. Methods: The study was based on the data of the EUROSTAR registry. Patient and anatomic characteristics, data regarding the procedure, postoperative complications, and the mortality of patients undergoing EVAR were retrieved from the database. Patients were divided into three groups: (1) no extensions, (2) proximal aortic cuffs, and (3) iliac limb extensions. Logistic regression and Cox proportional hazards models were used to compare significant influences of the use of cuffs or extensions on different outcomes relative to control patients, adjusted for patient and anatomic factors. Results: The overall cohort comprised 6668 patients: 4932 (74.0%) without extensions, 259 (3.9%) with an aortic cuff, and 1477 (22.2%) with an iliac endograft extension. Both the 30-day (2.3%-3.9%) and the all-cause mortality rates (23%-27% at 4 years) were similar in the three study groups. The use of proximal cuffs or iliac extensions did not have an effect on the incidence of endoleaks of any type (24%-32% at 4 years). The incidences of device kinking (P = .0344) and secondary transfemoral interventions (P = .0053) during follow-up were increased in patients in whom iliac limb extensions were used. In patients with aortic cuffs, no significant associations with altered outcome were observed. Conclusions. The use of iliac graft limb extensions at EVAR was associated with a higher incidence of kinking and secondary transfemoral interventions, whereas proximal aortic cuffs did not influence outcome.