Among the estimated 1.2 million persons living with human immunodeficiency virus (HIV) infection in the United States, approximately 14% have not had their HIV diagnosed. Certain populations, such as African Americans/blacks (in this report referred to as blacks), men who have sex with men (MSM), and Hispanics/Latinos (in this report referred to as Hispanics), are disproportionately affected by HIV. In areas where HIV prevalence is ≥0.1%, CDC recommends routine HIV screening in health care settings for persons aged 13-64 years. Implementation of HIV screening as part of routine care can increase the number of HIV diagnoses, destigmatize HIV testing, and improve access to care for persons with new HIV infections. Additionally, targeted testing in non-health care settings might facilitate access to persons in at-risk populations (e.g., MSM, blacks, and Hispanics) who are unaware of their status and do not routinely seek care. CDC analyzed data for 23 testing site types submitted by 61 health departments and 151 CDC-funded community-based organizations to determine 1) the number of HIV tests conducted, 2) the percentage of persons with new diagnoses of HIV infection (in this report referred to as new positives), and 3) the percentage of persons who were linked to HIV medical care within 90 days after receiving diagnoses at specific site types within health care and non-health care settings. The results indicated that, in health care settings, primary care and sexually transmitted disease (STD) clinics accounted for substantially more HIV tests than did other sites, and STD clinics identified more new positives. In non-health care settings, HIV counseling and testing sites accounted for the most tests and identified the highest number of new positives. Examining program data by site type shows which sites performed better in diagnosing new positives and informs decisions about program planning and allocation of CDC HIV testing resources among and within settings.