The Code of Federal Regulations is the permanent, subject-organized collection of rules issued by federal executive departments and agencies under authority Congress has delegated to them. It turns the broad laws Congress passes into the specific, enforceable requirements that govern things like workplace safety limits, banking practices, food labeling, and vehicle emissions. Rules in the Code carry the same binding force as a statute. The Code is divided into 50 subject-area titles and updated on a rolling schedule throughout the year.
How the Code Is Organized
The 50 titles each cover a broad subject. Title 7 covers Agriculture, Title 12 Banks and Banking, Title 21 Food and Drugs, Title 26 Internal Revenue, and Title 40 Protection of Environment, among others.1U.S. Nuclear Regulatory Commission. Table of CFR Titles and Chapters Title 35 is currently reserved and contains no regulations. The numbers stay fixed even when agencies are reorganized, so researchers always know where to look.
Within each title, the structure descends through layers. Chapters sit below titles and are usually assigned to a specific agency. Chapters break into parts, each covering a distinct regulatory program. Parts divide into sections, the most granular unit and the level at which most regulations are actually cited.2National Archives. About the Code of Federal Regulations Larger parts may also group related sections into subparts.
The layered design lets you start at a broad subject and drill down to the exact rule. Someone researching air quality standards would open Title 40, move to the chapter assigned to the Environmental Protection Agency, find the part covering air quality, and land on the specific section setting an emission limit.
How To Read a CFR Citation
A citation follows a consistent format. Take 21 C.F.R. § 101.9. The first number (21) identifies the title, in this case Food and Drugs. C.F.R. tells you the source is the Code of Federal Regulations. After the section symbol, the number before the decimal (101) is the part, and the number after (9) is the section within that part. A year in parentheses at the end of a formal citation indicates which edition is being referenced, which matters because regulations change over time.
You’ll see this format on more than legal documents. Federal contracts, compliance manuals, product labels, and industry standards all reference CFR sections. When a food label says nutrition facts are provided pursuant to 21 C.F.R. 101.9, that citation points to the exact rule dictating what appears on the label.
Where To Find and Track Regulations
Two federal resources give you access to the Code, and the difference between them matters.
The eCFR for Daily Use
The Electronic Code of Federal Regulations, at ecfr.gov, is updated daily and generally reflects Federal Register changes within two business days.3National Archives. About the Electronic Code of Federal Regulations For day-to-day compliance work this is the most practical tool, because recent amendments are already integrated into the regulatory text. You can browse by title, search by keyword, or navigate through the chapter-and-part structure.
One caveat: the eCFR is not an official legal edition. It’s an editorial compilation, and it does not provide legal notice to the public or judicial notice to the courts.3National Archives. About the Electronic Code of Federal Regulations For a legal filing, verify against the official edition.
The Official Annual Edition for Legal Filings
The Government Publishing Office publishes the official annual CFR edition through govinfo.gov in PDF format.4GovInfo. Code of Federal Regulations Each PDF represents the Code as it stood on its quarterly update date, providing a legally authoritative snapshot. This is the version courts recognize.
Tracking Changes Between Updates
Because the official edition updates on a quarterly cycle, there’s always a gap between the last published edition and the most recent Federal Register amendments. The List of CFR Sections Affected, or LSA, bridges that gap. Published monthly, it lists every CFR section proposed, amended, or revised since the most recent annual update, with the Federal Register page number where each change appears.5GovInfo. List of CFR Sections Affected Checking the LSA is how you confirm that the regulation you’re reading hasn’t been amended since the last annual edition.
How Rules Enter the Code
A regulation doesn’t appear overnight. The process starts when an agency publishes a proposed rule in the Federal Register, the daily journal of executive-branch regulatory action. That publication triggers a public comment period, typically 30 to 60 days, during which anyone can submit feedback. Under the Administrative Procedure Act, agencies must give interested persons an opportunity to participate through written comments, and the final rule must include a statement of its basis and purpose.6Office of the Law Revision Counsel. 5 USC 553 – Rule Making
Once the comment period closes and the agency finalizes the rule, it publishes the final version in the Federal Register. That final rule then migrates into its designated spot in the CFR during scheduled quarterly updates staggered across Titles 1 through 50 between January 1 and October 1.7U.S. Government Publishing Office. When Will the Code of Federal Regulations Be Published on GovInfo
A final rule generally cannot take effect until at least 30 days after it’s published, giving affected parties time to prepare.6Office of the Law Revision Counsel. 5 USC 553 – Rule Making Exceptions exist for rules that relieve restrictions or where the agency finds good cause to act faster and explains why.
Submitting a Public Comment
Regulations.gov is the central portal for public participation. When an agency publishes a proposed rule, it typically appears on the site with an open comment period. You can search a specific docket or browse by agency, then submit your comment through the online form or as a file upload.8Regulations.gov. Regulations.gov Comments that include data, real-world examples, or specific technical objections tend to carry more weight than general statements of support or opposition.
Agencies are legally required to consider significant comments and respond to them when publishing the final rule. If an agency ignores a substantial objection raised during the comment period, that failure can become grounds for a court to strike down the regulation later.
Legal Force and Penalties
Regulations in the CFR are enforceable against everyone they cover, and violations can trigger serious consequences. Agencies don’t have inherent authority to make rules; they get it from enabling acts where Congress delegates specific regulatory power. When an agency acts within that delegated authority, its rules bind the public.
Penalties vary widely by rule and agency. Some violations carry civil penalties of a few thousand dollars. Others reach far higher. A single motor vehicle safety violation can result in a civil penalty of up to $27,874 per occurrence, with a cap of over $139 million for a related series of violations.9eCFR. 49 CFR Part 578 – Civil and Criminal Penalties Clean Air Act violations can reach $124,426 per violation.10eCFR. 40 CFR 19.4 – Adjusted Civil Monetary Penalties Willful violations of workplace safety standards under OSHA can cost up to $165,514 each.11Occupational Safety and Health Administration. OSHA Penalties Some violations also carry criminal penalties including imprisonment.
The process by which agencies create and enforce these rules is governed by the Administrative Procedure Act, codified at 5 U.S.C. § 551 and the sections that follow.12Office of the Law Revision Counsel. 5 USC 551 – Definitions
Challenging a Regulation
If you believe a federal regulation was adopted improperly or exceeds the agency’s authority, you generally cannot go straight to federal court. The doctrine of exhaustion of administrative remedies requires you to work through the agency’s own internal appeal process first. Many statutes explicitly build in this requirement, and courts will dismiss cases filed by parties who haven’t completed it.
Once administrative remedies are exhausted, you can seek judicial review. A court can strike down a regulation it finds arbitrary, capricious, an abuse of discretion, in excess of the agency’s statutory authority, or adopted without following required procedures.13Office of the Law Revision Counsel. 5 USC 706 – Scope of Review
For decades, courts applied the Chevron doctrine, which required judges to defer to an agency’s interpretation of an ambiguous statute if that interpretation was reasonable. That changed in 2024. In Loper Bright Enterprises v. Raimondo, the Supreme Court overruled Chevron and held that courts must exercise their own independent judgment when deciding whether an agency has acted within its statutory authority.14Supreme Court of the United States. Loper Bright Enterprises v. Raimondo Judges can still give weight to an agency’s interpretation based on the thoroughness of its reasoning and its consistency over time, but that view no longer controls. The practical effect: the quality of the rulemaking record, including how well the agency responded to public comments, has become more important to whether a regulation survives review.