The Superintendent of Documents (SuDoc) classification system is an alphanumeric call number system used to shelve U.S. government publications. SuDoc call numbers are frequently given as part of bibliographic citations.

Each publication is assigned a letter based on the issuing department:

A = Agriculture Department

AE = National Archives and Records Administration

C = Commerce Department

CC = Federal Communications Commission

D = Defense Department

ED = Education

EP = Environmental Protection Agency

I = Department of Interior

J = Justice Department

L = Labor Department

OP = Overseas Private Investment Corporation

PREX = Executive Office of the President

S = State Department

TD = Transportation Department

Y = Congress

Subagencies within each department are assigned a number. The Census Bureau, an agency within the Commerce Department, for example, is given the number “3″ under the Commerce Department. All Census Bureau publications, therefore, have call numbers beginning with “C3″.

Within a subagency, each series is also assigned a number. For example, the Census Bureau’s MONTHLY RETAIL TRADE, SALES AND INVENTORIES series is given the number C 3.138/3:. Each individual publication in a series is then assigned a unique number or alphabetical symbol based on year, volume, series number, or title. This unique publication number follows the colon. Thus, C 3.138/3:92-3 is the SuDocs number for the March 1992 issue of MONTHLY RETAIL TRADE, SALES AND INVENTORIES.

So, the first half of the number (up to the colon) identifies the agency and series, and the last half identifies the specific publication. Publications are filed alphabetically by letter and then numerically, first grouped by subagency, then by series, and finally, arranged alphabetically or numerically within each series.

The number after the point is a whole number. It is NOT a decimal system.

Proper SuDocs Order:

  • D 1.1:
  • D 1.3:
  • D 1.12:
  • D 1.33:
  • D 1.122:

If the call number is the same to a certain point, then varies, the order is: Years → Letters → Numbers

Until the year 2000, the first number was dropped from years, so those years have 3 digits. Beginning with the year 2000, years are 4 digits.

Proper SuDocs Order:

  • EP 1.23:998
  • EP 1.23:A 62
  • EP 1.23:91-44
  • EP 1.23:600/998-103
  • EP 1.23:600/R-98-23

The U.S. government sometimes re-organizes or re-names departments and agencies, therefore material published at a different times may have different SuDoc numbers. For instance, material that was issued by the War Department is on our shelves under a “W” call number. Today, there is no War Department in the U.S. government. It has been replaced by the Defense Department. Material currently issued by the Defense Department is on our shelves with a “D” call number.

To sum up, it is important to remember that the material in the government documents collection is NOT arranged by subject. Instead the documents are shelved by numbers representing the agency that issued the document.