WHAT IS ALREADY KNOWN ON THIS TOPIC: The Centers for Disease Control and Prevention recommends that HIV screening be incorporated into routine care unless patients opt out, but most emergency departments (EDs) have not adopted routine screening. WHAT QUESTION THIS STUDY ADDRESSED: Will patients accept routine HIV testing in the ED without separate written consent or traditional pre- and posttest counseling? WHAT THIS STUDY ADDS TO OUR KNOWLEDGE: In this survey, 81% were willing to receive free HIV testing in the ED, but many required explanation of opt-out testing. HOW THIS MIGHT CHANGE CLINICAL PRACTICE: Patient acceptance may not be an important barrier to routine ED HIV screening. Nevertheless, screening is unlikely to be adopted in busy EDs unless payment and workload issues can be resolved. The yield of routine ED screening may be low in most settings.