Background: Endovascular aortic aneurysm repair (EVR) has a major financial impact on health care systems. We characterized reimbursement for index EVR hospitalizations among Medicare beneficiaries having surgery at Vascular Quality Initiative (VQI) centers. Methods: We linked Medicare claims to VQI clinical registry data for patients undergoing EVR from 2003 to 2015. Analysis was limited to patients fully covered by fee-for-service Medicare parts A and B in the year of their operation and assigned a corresponding diagnosis-related group for EVR. The primary outcome was Medicare's reimbursement for inpatient hospital and professional services, adjusted to 2015 dollars. We performed descriptive analysis of reimbursement over time and univariate analysis to evaluate patient demographics, clinical characteristics, procedural variables, and postoperative events associated with reimbursement. This informed a multilevel regression model used to identify factors independently associated with EVR reimbursement and quantify VQI center-level variation in reimbursement. Results: We studied 9,403 Medicare patients who underwent EVR at VQI centers during the study period. Reimbursements declined from $37,450 ± $9,350 (mean ± standard deviation) in 2003 to $27,723 ± $10,613 in 2015 (test for trend, P < 0.001). For patients experiencing a complication (n = 773; 8.2%), mean reimbursement for EVR was $44,858 ± $23,825 versus $28,857 ± $9,258 for those without complications (P < 0.001). Intestinal ischemia, new dialysis requirement, and respiratory compromise each doubled Medicare's average reimbursement for EVR. After adjusting for diagnosis-related group, several patient-level factors were independently associated with higher Medicare reimbursement; these included ruptured abdominal aortic aneurysm (+$2,372), additional day in length of stay (+$1,275), and being unfit for open repair (+$501). Controlling for patient-level factors, 4-fold variation in average reimbursement was seen across VQI centers. Conclusions: Reimbursement for EVR declined between 2003 and 2015. We identified preoperative clinical factors independently associated with reimbursement and quantified the impact of different postoperative complications on reimbursement. More work is needed to better understand the substantial variation observed in reimbursement at the center level.