Ask a Librarian

Find what you need in our searchable FAQ.

What is SuDoc Classification?

39 views   |   0   0   |   Last updated on Jun 29, 2016    SuDoc classification government resources


It is how government documents are classified.


The SuDocs (Superintendent of Documents) system is straightforward on the surface--A call numbers are publications of the Department of Agriculture, C is Commerce, D is Defense, and so on. This type of system is called a provenance system--it organizes publications based upon issuing agency.

There are exceptions to the straightforward letters, of course: Y 1 call numbers are general publications of Congress--House and Senate Documents and Reports, Y 3 call numbers are independent boards and commissions, and Y 4 call numbers are House and Senate Committee hearings and publications.

This tutorial is not intended to explain the classification system in great detail. It's doubtful that you need to know that much about the system, but just want to be able to find, shelve or file items which are in SuDocs call number order. If you do want to understand more about the construction of the call number and what the numbers mean, there are several places on the Federal Depository Library Program web site where you can learn much more.


Focus on the Three Things You Really Need to Know

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

Decimal vs. SuDocs Order

Decimal Order

SuDocs Order

D 1.1:

D 1.1:

D 1.12:

D 1.3:

D 1.122:

D 1.12:

D 1.3:

D 1.33:

D 1.33:

D 1.122:


2. 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 will be 4 digits.

Years/Letters/Numbers Order

Example 1

Example 2

A 1.35:993

EP 1.23:998

A 1.35:R 42

EP 1.23:A 62

A 1.35:R 42/995

EP 1.23:91-44

A 1.35:R 42/2

EP 1.23:600/998-103

A 1.35:321

EP 1.23:600/R-98-23


3. If the call number stem (the numbers before the colon) has numbers slashed onto the base number, the base number comes first, followed by the slashed numbers in order. The same rule applies to numbers dashed onto other numbers or letters.

Slashes/Dashes Order

Example 1

Example 2

C 3.186:

EP 1.23:

C 3.186/2:

EP 1.23/A:

C 3.186/7:

EP 1.23/A-2:

C 3.186/7-3:

EP 1.23/2:

C 3.186/9:

EP 1.23/2-2: