Introduction: The progression of aneurysmal disease in the common iliac arteries (CIAs) after EVAR remains an insufficiently investigated field. The purpose of this study is to investigate the long-term outcomes of standard elective EVAR with a variety of last-generation bifurcated aortic endografts in relation with the progression of aneurysmal disease in the CIAs. Methods: This is a prospective cohort study of 168 patients, who were treated with six different endografts between 2013 and 2018 and completed the 5-year computed tomography aortoangiography (CTA) follow-up. Postoperative CTA analysis included CIA measurements at four diameters' points and two length levels in three postoperative time spots: first, 24th, and 60th months. All EVAR-related adverse events were recorded, including migrations, endoleaks, limb occlusions, reinterventions, ruptures, and mortality. Results: At both time intervals, a significant and nearly linear dilatation and elongation of CIAs was evident. The mean percent increase, among all diameter points measured, was 11.7% at 24 months and 22.8% at 60 months (p < 0.001) with a nearly constant mean increase rate by 0.07 mm per month. The corresponding monthly elongation rate of total CIA length was 0.26 mm at 24 months and 0.34 mm at 5 years (p < 0.001). The respective monthly lengthening of CIAs' uncovered (from stent graft) segment was 0.10 and 0.15 mm, and the overall increase rate at 60 months was up to 53.9% (p < 0.001). A total of 20 EVAR-related events were recorded, and multivariate analysis revealed that CIA dilatation served as a significant and independent predictor of long-term EVAR failures, increasing the likelihood of adverse events by 2.8-fold. Conclusions: Analysis of long-term geometric CIA remodeling after a standard EVAR revealed a significant progression of aneurysmal disease in CIAs, which was associated with worsening EVAR outcomes and emphasizes the importance of a rigorous and extensive follow-up protocol to maintain the long-term EVAR effectiveness.