PurposeThis article examines if there is evidence of racial or gender bias in email reference services in American public and academic libraries.Design/methodology/approachUsing a two-by-two study design and an unobtrusive data collection, the authors conducted two studies in which the authors sent 1,960 email requests to 505 academic and public libraries. Requests in both studies differed in the perceived identity of the user as indicated by their name, and the counterbalanced method was utilized to control for intervening variables. Based on content analysis of the responses, the authors examined the statistical significance of the differences by race, gender and race by gender.FindingsOverall, the authors found equitable service to users regardless of their race and gender; at times, however, there was evidence of favorable service to the White female in academic and public libraries and to the Black male in academic libraries.Originality/valueThere is little research into potential bias in email reference services in both academic and public libraries in the United States of America. Yet, following the rise of the Black Lives Matter Movement in 2020, there has been an increased focus on racial equality in library services and the American Library Association (ALA) Code of Ethics was modified accordingly. The authors' study makes significant contributions to the increasing body of research on racial and gender equality in online library services.