In-hospital outcomes associated with abdominal aortic aneurysm (AAA) repair are well described. However, little is known about post-discharge readmission rates, lengths of stay, associated mortality, and costs. We examined 206 consecutive patients who underwent AAA repair at two American hospitals between 1998 and 2000. Index hospitalization and 6-month readmission data were extracted from a resource and cost accounting system used by both hospitals. Among the 206 patients, 183 survived until discharge (mortality rate 11.2%). Among the surviving patients, 38 (21.0%) were readmitted within 6 months. Half of the readmissions occurred within two weeks of discharge, with patients presenting with a diverse array of complications. Nonelective repair and diabetes mellitus were independent predictors of hospital readmission (OR = 2.83, 95% CI = 1.25-6.40, p = 0.01; OR = 6.60, 95% CI = 1.02-42.4, p = 0.047, respectively). For each readmission, the mean length of stay was 10.7 +/- 2.5 days and the mean cost was dollar 13,397 +/- 3,381. The cumulative number of hospital days during the 6 months post-discharge was 17.7 +/- 3.5 days for each readmitted patient and the mean per-patient total cost was dollar 23,262 +/- 5,478. The mortality rate among readmitted patients was 13.2%. Overall, readmissions following AAA repair accounted for a cost >50% over and above the cost of the readmitted patients' index hospitalization. Hospital readmissions are common during the 6 months following AAA repair. Patients who are readmitted experience long lengths of stay and high mortality rates, and their care incurs high costs.