Similarly to official and unofficial reporters for cases, there are official and unofficial codes for federal statutes.
The United States Code (U.S.C.) is the official code for federal statutes. A new print edition is published every six (6) years, and supplement that is updated annually between the new editions. If the statute you are citing is currently in effect, The Bluebook says to cite to the United States Code if it contains the current version of the statute. (See Rule 12.3)
The United States Code Annotated (U.S.C.A.) and the United States Code Service (U.S.C.S.) are unofficial codes for federal statutes. These are updated in print multiple times a year. Due to the legislature's enactments, amendments, and repeals happen so frequently, citing to the unofficial code will often be the case due to the most current version of the statute not appearing in the United States Code (U.S.C.) yet.
The most current edition of the United States Code (U.S.C.) can be found on govinfo.gov.
The most current edition of the United States Code Annotated (U.S.C.A) can be found on Westlaw, and the most current edition of the United States Code Service (U.S.C.S.) can be found on LexisNexis.
Elements to a statute in the United States Code:
* The date in the citation is the year of the code edition cited; it is not the year a statute was enacted or last amended.
Here is an example:
5 U.S.C. § 553 (2023)
Adding the Name of the Statute
The Bluebook adds the name of the statute in some instances, including:
(See Rule 12 and Rule 12.3.1(a))
For example, the statute above (5 U.S.C.§ 520) is part of the Administrative Procedure Act of 1946, 60 Stat. 237, which is currently codified in Title 5 of the United States Code. The specific provision (§ 553) was Section 4 of the Administrative Procedure Act of 1946.
If one needed to cite the entire Administrative Procedure of 1946 as currently codified in the United States Code, that citation would look like:
Administrative Procedure Act of 1946, 5 U.S.C. §§ 551-559 (2023)
If it is necessary to include the statutory name and original section number of § 553 in a citation, that citation would look like:
Administrative Procedure Act of 1946 § 4, 5 U.S.C. § 553 (2023)
Elements to a statute in the United States Code Annotated or United States Code Service
*The date in the citation is the date on the copyright page or the date on the title page of the specific volume containing the statute, not the year the statute was enacted or last amended.
As aforementioned, United States Code Annotated is published by West and United States Code Service is published by LexisNexis.
Here are some examples of statutes cited to these unofficial codes:
20 U.S.C.A. § 76d (West 2025)
38 U.S.C.S. § 1110 (LexisNexis 2025)
Supplements are updated for the United States Code annually, and the United States Code Annotated and United States Code Service are updated regularly with the most up-to-date version being the online versions.
If a statute is amended or a new statute is enacted, the changes can appear in supplemental or pocket parts (small pamphlets inserted in the back of a volume), and this will need to be indicated in the citation. Because a new edition of United States Code is only published every six (6) years, supplements or pocket parts are sent out every year. By the time it is time to publish a new edition, there are five (V) supplements to the U.S.C.. The date to the supplement is located on the front page.
Say, for example, that § 553 of the U.S.C. (citation above) had been amended since the 2023 edition (which it has not) and the amendment appeared in the first annual supplement (Supplement I), there are two (2) ways to cite depending on the amendment.
If the statute is amended completely such that the current version appears only in the supplement, the citation looks as follows:
5 U.S.C. § 553 (Supp. I 2025)
If the statute is amended only partially, meaning that there are parts of the statute in the main volume and in the supplement, the citation looks as follows:
5 U.S.C. § 553 (2023 & Supp. I 2025)
