This study compared the cost-effectiveness of carotid artery stent placement (CAS) versus carotid endarterectomy (CEA) in high-risk patients based on data from the SAPPHIRE trial. The mean cost per quality-adjusted life year (QALY) gained was higher for CAS ($16,223) than for CEA ($12,745). The incremental cost-effectiveness ratio estimated CAS to be $67,891 more expensive per QALY gained than CEA, with a wide range. Although CAS was not inferior to CEA for outcomes, its higher cost offsets the marginal benefit for high-risk patients.