Chicago Notes-Bibliography is the citation system most humanities writers know best. History monographs, art-history articles, classics books, religious-studies dissertations, and music-theory papers nearly all use it. If your discipline reads primary sources closely, footnotes the texture of its argument, and pairs that with a comprehensive bibliography, this is the system built for the job.
The canonical reference is the Chicago Manual of Style, 18th Edition, published by the University of Chicago Press in 2024. CMOS keeps a public companion at chicagomanualofstyle.orgwith a Q&A archive and free articles. The full Manual is available to subscribers online and in print. This blog post is an orientation. It is not a rulebook and does not replace the Manual when you need a canonical answer.
Where Chicago Notes-Bibliography came from and who uses it
The University of Chicago Press published the first edition of A Manual of Style in 1906. Notes-Bibliography is the older of the Manual’s two citation systems and the one most readers think of when they think of Chicago. It carries the heritage of footnoted scholarship: an argument that progresses in the main text while supporting evidence, alternative readings, and bibliographic detail unfold in numbered notes beneath.
Disciplines that typically use Chicago Notes-Bibliography include history, art history, classics, archaeology, religious studies, philosophy (in many departments), musicology, theatre studies, and large parts of literary studies that prefer Chicago over MLA. Many history journals also use Chicago Notes-Bibliography. If your discipline is one of these, the system is probably already the local norm.
The mechanics: spelling, punctuation, and usage
The mechanics rules of Chicago Notes-Bibliography are identical to those of Chicago Author-Date. Both systems share the same Manual chapters on grammar, usage, numbers, and punctuation. Only the citation system differs.
American spelling is the default, with Merriam-Webster’s Collegiate Dictionary as the tiebreaker. American punctuation places commas and periods inside closing quotation marks and uses the serial comma. Headline-style capitalization is used for book and journal titles in running text and in notes and the bibliography. Article titles use headline-style capitalization in notes and the bibliography (this differs from Author-Date, which uses sentence case for article titles in the reference list). Italic is used for book and journal titles. Quotation marks for article and chapter titles.
The citation system, at a glance
Notes-Bibliography is a two-part system. In the running text, the writer adds a superscript number at the end of the sentence (or the relevant clause), and a numbered note carries the citation, either at the foot of the page or grouped at the end of the document. The first time you cite a source, the note carries the full citation. Every subsequent time you cite the same source, the note carries a shortened citation that names the author and a short version of the title.
The bibliography sits at the end of the document, alphabetical by first author surname, formatted with a hanging indent. The bibliography is required for most academic work, even though every cited source has appeared in full at least once in the notes; the bibliography lets a reader see the full list at a glance.
The notes
First full citation
The first time a source is cited, the note carries the author name in normal order (first name first), the title, the publication information, and the specific page or pages being cited. Pieces are separated by commas rather than periods. The note ends with a full stop.
Examples below. Sources are invented for illustration.
- Book, first full citation: 1. Mara Stein, Quiet Revisions: Editing as a Craft (Chicago: Bracewell Press, 2019), 47.
- Journal article, first full citation: 2. Adaeze C. Okonkwo, “Reading between the Citations,” Journal of Humanistic Inquiry14, no. 2 (2022): 121–44, https://doi.org/10.1234/jhi.2022.047.
- Chapter in an edited book, first full citation: 3. Jiwon Choi, “On Voice,” in The Shape of Scholarly Prose, ed. Mara Stein (Chicago: Bracewell Press, 2021), 88–112.
- Website article, first full citation: 4. Riya Patel, “Form and Feeling in Recent Criticism,” Modern Letters Review, March 14, 2022, https://example.org/mlr/12345.
Shortened citations
Every subsequent citation of the same source uses a shortened form: the author surname, a short version of the title, and the page being cited.
- Book, shortened citation: 5. Stein, Quiet Revisions, 122.
- Journal article, shortened citation: 6. Okonkwo, “Reading between the Citations,” 130.
When two consecutive notes cite the same source and the same passage, recent CMOS recommends a repeated shortened citation rather than ibid. The repeat is more durable when notes get reordered during editing.
Multiple authors in a note
For one to three authors, all names appear in the first full citation and in the shortened citation. For four or more authors, the first author name appears followed by et al. in the shortened citation; the first full citation lists all the authors. The cutoff is the same four-author threshold used in Chicago Author-Date.
The bibliography
The bibliography starts on a new page after the body of the document with the heading “Bibliography” centered at the top. Entries are alphabetical by first author surname, formatted with a hanging indent. Author names are inverted (surname first) in the bibliography, in contrast with the notes, where the first author appears in natural order.
Each bibliography entry follows the four-part skeleton: who, when, what, where, with periods between the major divisions. The bibliography entry contains the same information as the first full note, but reorganized: author surname-first, year directly after author (or at the end depending on entry type), and elements separated by periods rather than commas.
Examples to internalize
Four sample bibliography entries. The same sources used in the note examples above appear here in bibliography form. All authors and works are invented.
- Book: Stein, Mara. Quiet Revisions: Editing as a Craft. Chicago: Bracewell Press, 2019.
- Journal article: Okonkwo, Adaeze C. “Reading between the Citations.” Journal of Humanistic Inquiry14, no. 2 (2022): 121–44. https://doi.org/10.1234/jhi.2022.047.
- Chapter in an edited book: Choi, Jiwon. “On Voice.” In The Shape of Scholarly Prose, edited by Mara Stein, 88–112. Chicago: Bracewell Press, 2021.
- Website article: Patel, Riya. “Form and Feeling in Recent Criticism.” Modern Letters Review, March 14, 2022. https://example.org/mlr/12345.
Things to remember about the bibliography
- Alphabetical order by first author surname; secondary sort by title when an author has multiple entries.
- Author surname first in bibliography entries (unlike notes, where the first author appears in natural order).
- Hanging indent on every entry.
- Periods separate the major divisions (rather than commas, which separate elements within a note).
- Headline-style capitalization for both book and article titles in Notes-Bibliography (article titles do not switch to sentence case as they do in Author-Date).
- DOIs as URLs when available, with the https://doi.org/ prefix.
What RightMyWork does with Chicago Notes-Bibliography
When you pick Chicago Notes-Bibliography on the upload screen, the editor applies CMOS 18 Notes-Bibliography conventions across your document. Notes are reviewed for first-full versus shortened citation patterns, including the recognition of repeated sources and the conversion to the shortened form on subsequent appearances. Bibliography entries are reviewed for author inversion, headline-style title capitalization, italic on the right elements, and consistency with the notes.
Every change lands as a tracked change in Word. Citations referencing works missing from the bibliography are flagged in a comment rather than guessed at, and unusual source types surface a query rather than an opinionated rewrite. Citations using the older ibid. convention can be flagged for conversion to the modern shortened form.
Where to go from here
For the rules in their canonical form, the CMOS Q&A and online articles are the best free resource, and the printed Chicago Manual of Style 18th edition is the definitive reference. Both are produced by the people who define the style.
When you are ready to apply Chicago Notes-Bibliography to your draft, the upload form on the homepage is one click away. The first 3,000 words on a new account are free.