The European Reading Room is the primary point of contact for researchers interested in materials from and about Bulgaria. The Reading Room maintains a collection of several hundred reference books for Bulgaria, with general encyclopedias, subject encyclopedias, biographical dictionaries, language dictionaries, bibliographies, census data, and other reference materials.

Also available in the European Reading Room are most of the Bulgarian newspapers on microfilm, issues of unbound periodicals and print newspapers from Bulgaria, several ephemera collections, and a pamphlet collection containing over 700 items from Bulgaria. In the European Reading Room cage a number of unique materials are kept on hand due to rarity or the need for displays. Cage materials include a journal volume once owned by Tsar Ferdinand I of Bulgaria, the first Bulgarian grammar written in English, and two political posters from the early 1990s. All cage materials are available upon request at the European Reading Room reference desk. Several special items available in the European Reading Room are described below.