About Code of Federal Regulations

The Code of Federal Regulations (CFR) annual edition is the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. It is divided into 50 titles that represent broad areas subject to Federal regulation. The 50 subject matter titles contain one or more individual volumes, which are updated once each calendar year, on a staggered basis. The annual update cycle is as follows: titles 1-16 are revised as of January 1; titles 17-27 are revised as of April 1; titles 28-41 are revised as of July 1, and titles 42-50 are revised as of October 1. Each title is divided into chapters, which usually bear the name of the issuing agency. Each chapter is further subdivided into parts that cover specific regulatory areas. Large parts may be subdivided into subparts. All parts are organized in sections, and most citations to the CFR refer to material at the section level.


The online CFR is a joint project authorized by the publisher, the National Archives and Records Administration's (NARA) Office of the Federal Register (OFR), and the Government Publishing Office (GPO) to provide the public with enhanced access to Government information.


CFR volumes are added to FDsys concurrent with the release of the paper editions. When revised CFR volumes are added, the prior editions remain on FDsys as a historical set. FDsys currently contains titles from 1996 to the present.


"[Reserved]" is a term used as a place holder within the Code of Federal Regulations. An agency uses "[Reserved]" to simply indicate that it may insert regulatory information into this location some time in the future. Occasionally "[Reserved]" is used to indicate that a portion of the CFR was intentionally left empty and not accidentally dropped due to a printing or computer error.


Due to the update schedule of the CFR, the List of Sections Affected (LSA) provides a cumulative list of CFR sections that have been changed at any time since each CFR title was last updated.


In the official paper bound version and the official PDF versions of 2007 edition of Title 49 volume 6 parts 400-599, the header incorrectly reads "(10-1-06 Edition)" and should have read "(10-1-07 Edition)."

Parallel Table of Authorities and Rules for the Code of Federal Regulations and the United States Code

The Parallel Table of Authorities and Rules lists rulemaking authority (except 5 U.S.C. 301) for regulations codified in the Code of Federal Regulations. Also included are statutory citations which are noted as being interpreted or applied by those regulations. The table is divided into four segments: United States Code citations, United States Statutes at Large citations, public law citations, and Presidential document citations. Within each segment the citations are arranged in numerical order:

  • For the United States Code, by title and section;

  • For the United States Statutes at Large, by volume and page number;

  • For public laws, by number; and

  • For Presidential documents (Proclamations, Executive orders, and Reorganization plans), by document number.


Entries in the table are taken directly from the rulemaking authority citation provided by Federal agencies in their regulations. Federal agencies are responsible for keeping these citations current and accurate. Because Federal agencies sometimes present these citations in an inconsistent manner, the table cannot be considered all-inclusive. The portion of the table listing the United States Code citations is the most comprehensive, as these citations are entered into the table whenever they are given in the authority citations provided by the agencies. United States Statutes at Large and public law citations are carried in the table only when there are no corresponding United States Code citations given.


The current table was revised as of January 1, 2017 and is available at  PDF | Text  

Code of Federal Regulations Citations

The following describes how information is contained in a CFR citation.

  • Title: Is the numeric value to the left of "CFR".

  • Part: Is the numeric value to the right of "CFR" and preceding the period (".").

  • Section/Subpart: Is the numeric value to the right of the period (".").

    • A subpart is a letter of the alphabet (A-Z) that is used to retrieve an entire subpart of the CFR rather than many individual sections. For example: Subpart E.

  • Revision Year: The four digit year from the "Revised as of" text represents the year being cited. The revision year is not always available when the CFR is cited.

The following example illustrates information contained in a CFR citation.


21 CFR 310.502 Revised as of April 1, 1997

  • Title: 21

  • Part: 310

  • Section: 502

  • Year: 1997

Code of Federal Regulations XML Files

The U.S. Government Publishing Office (GPO) and the National Archives' Office of the Federal Register (OFR) partnership is offering bulk data downloads of Code of Federal Regulations XML files to the general public via and FDsys at Information on the legal status, authenticity, and schema of the Code of Federal Regulations XML renditions can be found in the User Guide Document - Code of Federal Register XML Rendition at


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