The Institute of Museum and Library Services (IMLS), a federal agency, conducts a national census of America's public libraries, including main libraries, branches, and bookmobiles. Their latest data, published in September 2025, reports over 17,000 public library outlets across the United States.
This count uses the institutional standard for measuring library presence, which includes all service points where the public can access library resources, not just standalone buildings. The American Library Association and a recent GAO study both confirm these numbers, emphasizing their reliability.
Counting public library outlets this way allows for a direct comparison with how other national chains report location counts. The margin over similar metrics for McDonald's locations further confirms the comprehensiveness of this figure.