The American Philatelic Research Library (APRL), based in Bellefonte, Pennsylvania, is the largest public philatelic library in the United States.

The library serves the needs of the members of the American Philatelic Society (APS) – with which it is closely affiliated and shares premises – and the public.

Donations are treated as a charitable deduction for the purposes of United States federal income tax.

Three members are elected by the American Philatelic Society membership, three are appointed by the President of the APS and three are elected by the founders and patrons of the APRL.

The library publishes a quarterly magazine, the Philatelic Literature Review, which includes book reviews, bibliographies, and other relevant content.