Approximately 44% of adults aged 18–59 years had ever been tested for HIV (other than blood donations) during 2007–2010, nearly the same as during 2003–2006. From 2003–2006 to 2007–2010, no significant change was observed for non-Hispanic white and Mexican-American adults in this age group. A significant increase was observed in the percentage of non-Hispanic black adults aged 18–59 years (from 57% to 64%) who had ever been tested for HIV. During both periods, non-Hispanic black adults had a significantly higher prevalence of any lifetime HIV testing compared with non-Hispanic white and Mexican-American adults.