To cite a federal regulation in standard legal form, write the title number, the abbreviation C.F.R., a section symbol and section number, and the edition year in parentheses: 21 C.F.R. § 101.3 (2026). That format covers regulations that have been codified in the Code of Federal Regulations. If the rule you need hasn’t been codified yet — a proposed rule, a very recent final rule, or a notice that will never enter the CFR — you cite the Federal Register instead, using volume, page, and date: 91 Fed. Reg. 18,042 (Mar. 15, 2026). Everything else about citing federal regulations is a variation on those two forms.
Which Publication to Cite
The choice between the two formats depends on where the regulation currently lives. The Federal Register is the daily publication where agencies first release proposed rules, final rules, and notices.1National Archives. About the Federal Register The Code of Federal Regulations organizes final rules by subject into 50 titles once they are codified.2eCFR. 1 CFR Part 21 Subpart A – Code Structure
The working rule: once a regulation has been codified in the CFR, cite the CFR. Cite the Federal Register only for rules that haven’t made it in yet, for preamble language, and for administrative notices that never enter the CFR at all.
The CFR Citation, Element by Element
A CFR citation has four parts, run together on one line with no punctuation between them and nothing italicized:
- Title number — the broad subject area, such as 21 for Food and Drugs or 29 for Labor.
- C.F.R. — the abbreviation for the Code of Federal Regulations.
- Section symbol and number — the § symbol followed by the section, such as § 101.3.
- Year — the edition year of the CFR volume, in parentheses.
Put together: 21 C.F.R. § 101.3 (2026). The year identifies which annual edition of the CFR you consulted, which matters because the text of a regulation can change from one edition to the next.
Pinpoint Citations to Subsections
When you want to point to a specific paragraph inside a section, add the subsection designation directly to the section number. A citation to subsection (a) reads 21 C.F.R. § 101.3(a) (2026). A deeper reference to paragraph (b)(1) reads 21 C.F.R. § 101.3(b)(1) (2026). This saves the reader from scanning an entire section to find the sentence you mean.
Multiple Sections and Whole Parts
To cite more than one section, use a double section symbol and separate the numbers with commas: 21 C.F.R. §§ 101.3, 101.4 (2026). For a consecutive range, use an en dash: 21 C.F.R. §§ 101.1–101.9 (2026).
To cite an entire part rather than a single section, replace the section symbol with the abbreviation “pt.”: 29 C.F.R. pt. 1980 (2026). Use this when you’re discussing a regulatory scheme as a whole.
Federal Register Citations
Federal Register citations are built around volume and page number rather than subject. The elements are:
- Volume number — assigned to each calendar year of publication.
- Fed. Reg. — the abbreviation for the Federal Register.
- Starting page number — where the document begins in that volume.
- Date — the full publication date, in parentheses.
A final rule published on March 15, 2026 in volume 91 starting at page 18,042 is cited: 91 Fed. Reg. 18,042 (Mar. 15, 2026). Use a comma in page numbers above 9,999 and abbreviate the month.
Proposed Rules and “To Be Codified”
If the document is a proposed rule, mark that inside the date parenthetical: 91 Fed. Reg. 18,042 (proposed Mar. 15, 2026). A proposed rule does not carry the force of law and may never be finalized, so the label matters.
When a final rule identifies where it will appear in the CFR, add that in a second parenthetical: 91 Fed. Reg. 18,042 (Mar. 15, 2026) (to be codified at 42 C.F.R. pt. 405). For a proposed rule, both parentheticals appear: 91 Fed. Reg. 18,042 (proposed Mar. 15, 2026) (to be codified at 40 C.F.R. pt. 86).
Short Forms After the First Citation
Once you’ve given a full citation, subsequent references can be shortened. For a codified regulation, drop the title and year: § 101.3. For a Federal Register document, keep the volume and abbreviation and use “at” to point to a different page: 91 Fed. Reg. at 18,050.
“Id.” works when you’re citing the same authority as the immediately preceding citation. If your last citation was 21 C.F.R. § 101.3 (2026) and you’re citing it again, write Id. To move to a different subsection of the same regulation, write Id. § 101.4. One limit: Id. only works when the preceding citation referenced a single authority. If the previous citation listed several sources, use the ordinary short form instead.
Why the Year Matters
The edition year isn’t decorative. The CFR is revised on a staggered quarterly schedule, so different titles are current as of different dates:3National Archives. About the Code of Federal Regulations
- January 1 — Titles 1–16
- April 1 — Titles 17–27
- July 1 — Titles 28–41
- October 1 — Titles 42–50
A citation to Title 7 with the year 2026 points to the version in force as of January 1, 2026. A citation to Title 42 might still show 2025 as the current edition until the October 1, 2026 revision comes out. Getting the year right ensures your reader opens the same text you relied on.
When You Found the Regulation Online
Most readers reach federal regulations through the Electronic Code of Federal Regulations at ecfr.gov. The eCFR is updated daily and is more current than the annual print edition, but it isn’t the official legal edition of the CFR. It’s an editorial compilation produced by the Office of the Federal Register and the Government Publishing Office.4Govinfo. Code of Federal Regulations – GovInfo
For legal writing following Bluebook conventions, cite the official annual CFR edition by year even if you read the text on ecfr.gov. Treat the eCFR as a research tool rather than the cited source. When the language you need reflects an amendment that hasn’t yet reached the annual print edition, cite the Federal Register version of the final rule instead. The official annual CFR is also available for free through govinfo.gov.4Govinfo. Code of Federal Regulations – GovInfo
APA Format for Non-Legal Writing
Researchers and students using APA style use a slightly different form. An APA reference list entry starts with the name of the regulation, followed by the title number, C.F.R., the section symbol and number, the year, and a URL if available. For example: Protection of Human Subjects, 45 C.F.R. § 46 (2009). The in-text citation uses the regulation’s name and year: (Protection of Human Subjects, 2009). The difference from Bluebook form is that the regulation’s name goes at the front; Bluebook citations omit it unless the regulation is commonly known by name.
Mistakes That Break a Citation
The most damaging error is the wrong year. If you cite 29 C.F.R. § 1910.134 (2024) but the provision was amended in 2025, your reader finds different language than what you quoted. Confirm that the edition year matches the text you’re relying on.
The second common problem is citing the CFR for a rule that exists only in the Federal Register. A proposed rule has no CFR citation because it hasn’t been codified, and citing it as if it does creates a dead reference. The reverse mistake — citing the Federal Register for a rule codified years ago — sends readers into archived volumes when the CFR already has a clean, current version.
Watch also for stale eCFR references. Because the eCFR updates daily, language you read there today may reflect an amendment the annual CFR won’t incorporate for months. If your citation says 2025 but the quoted text was added by a Federal Register notice published last week, the citation and the quotation don’t match. Check the Federal Register for the most recent amendment date and cite accordingly.