The Free Library of Philadelphia is the public library system that serves Philadelphia, Pennsylvania. It is the 13th-largest public library system in the United States. Unique among public libraries in the United States, it is neither a city agency nor a nonprofit organization; instead, it is governed by both an independent city agency managed by its own board of directors and a separate nonprofit organization, The Free Library of Philadelphia Foundation.
In fiscal year 2015, the Free Library hosted nearly six million patrons in person and ten million more online.