We sought to evaluate the relative cost of surgical and device closure of atrial septal defect. Device closure for atrial septal defects is becoming an alternative to surgical closure. We examined the hospital-generated cost data in 13 patients who underwent surgical repair and 15 patients who underwent device closure of an atrial septal defects (ASD) or patent foramen ovale (PFO) during a prospective clinical trial of the device. The cost of device closure of ASD was 7,837 dollars less on average than surgical closure when the cost of the occlusion device was excluded (device closure cost 7,397 dollars +/- 2,822 dollars, surgical closure cost 15,234 dollars +/- 3,851 dollars; P < 0.001). When adjusted for a 5% failure rate of device closure, the cost savings was 7,076 dollars. Device closure of ASD results in substantial hospital-related cost savings that will be an important consideration once new devices are approved for clinical use.