Chicago Style Citation Guide (18th Edition)
Meta description: Learn how to cite sources in Chicago style using the 18th edition (2024) of the Chicago Manual of Style — with notes, bibliography, and examples for every source type.
The Chicago Manual of Style is one of the most widely used citation systems in academic writing. This guide covers Notes-Bibliography style (the version most students use) and reflects the 18th edition, released in September 2024 — the first major update in seven years.
Need MLA or APA instead? Check out our MLA format guide and APA format guide.
What Changed in the 18th Edition
If you learned Chicago style from the 17th edition, here's what's different:
- No more place of publication. Book citations now only need the publisher and year — you can drop the city (e.g., New York:).
- No page ranges for chapters in the bibliography. List the specific page(s) you cited in the note; the bibliography entry no longer needs a full page range.
- "Ibid" is out. Even for a repeated source and page, use a shortened citation (Last name, page #) instead of "Ibid."
- Up to six authors can now be listed in a citation before switching to "et al." (previously the cutoff was three).
- New guidance for AI-generated content and expanded coverage of self-published and inclusive-language sources.
Notes and Bibliography: The Basics
Chicago's Notes-Bibliography system has two parts:
- Notes — footnotes (bottom of the page) or endnotes (end of the document), marked by a superscript number in the text.
- Bibliography — an alphabetized list of every source, placed at the end of the paper.
Bibliography formatting rules:
- Single-spaced, with a hanging indent on the second line
- Entries alphabetized by author's last name
Footnotes and Endnotes
The first time you cite a source, write the full citation. After that, use a shortened citation:
Last Name, Short Title, page number.
Example:
- Philip R. Cateora et al., International Marketing (McGraw Hill, 2020), 292–94.
- Cateora et al., International Marketing, 28–29.
- Cateora et al., 28–29.
For titles longer than four words, shorten them by keeping the key words and dropping a leading "A" or "The" (e.g., Fried Green Tomatoes at the Whistle Stop Cafe → Fried Green Tomatoes).
With up to three authors, list them all; with four to six, list all six in the bibliography (first only + "et al." in notes); with more than six, list the first three followed by "et al."
Common Source Types
Book (one author)
Note: Sam Staggs, Born to Be Hurt: The Untold Story of Imitation of Life (St. Martin's Press, 2009), 84.
Bibliography:
Staggs, Sam. Born to Be Hurt: The Untold Story of Imitation of Life. St. Martin's Press, 2009.
Book (multiple authors)
Note: Ella Shohat and Robert Stam, Unthinking Eurocentrism: Multiculturalism and the Media (Routledge, 1994), 24–28.
Bibliography:
Shohat, Ella, and Robert Stam. Unthinking Eurocentrism: Multiculturalism and the Media. Routledge, 1994.
Chapter in an edited book
Note: Kathleen Doyle, "The Queen Mary Psalter," in The Book by Design, ed. P. J. M. Marks and Stephen Parkin (University of Chicago Press, 2023), 64.
Bibliography:
Doyle, Kathleen. "The Queen Mary Psalter." In The Book by Design, edited by P. J. M. Marks and Stephen Parkin. University of Chicago Press, 2023.
(No page range needed in the bibliography — just cite the page in the note.)
Journal article (print or online)
Note: Trine Schreiber, "Conceptualizing Students' Written Assignments," Journal of Documentation 70, no. 3 (2014): 346–63, https://doi.org/10.1108/JD-01-2013-0002.
Bibliography:
Schreiber, Trine. "Conceptualizing Students' Written Assignments." Journal of Documentation 70, no. 3 (2014): 346–63. https://doi.org/10.1108/JD-01-2013-0002.
Website / web page
Note: Sujan Patel, "15 Must-Have Marketing Tools for 2015," Entrepreneur, January 12, 2015, http://www.entrepreneur.com/article/241570.
Bibliography:
Patel, Sujan. "15 Must-Have Marketing Tools for 2015." Entrepreneur. January 12, 2015. http://www.entrepreneur.com/article/241570.
E-book
Note: Michael J. Baker, The Marketing Book (Butterworth-Heinemann, 2002), 89.
Bibliography:
Baker, Michael J. The Marketing Book. Butterworth-Heinemann, 2002.
Newspaper or magazine article
Note: George J. Church, "Sunny Mood at Midsummer," Time, July 18, 1983, 56–59.
Bibliography:
Church, George J. "Sunny Mood at Midsummer." Time, July 18, 1983.
Blog post
Cite it like an online article, adding "(blog)" after the blog's name.
Note: Shannon Miller, "Valentine Ideas Using Digital Tools," The Library Voice (blog), January 20, 2016, http://vanmeterlibraryvoice.blogspot.com/2016/01/valentine-ideas-using-digital-tools.html.
Bibliography:
Miller, Shannon. "Valentine Ideas Using Digital Tools." The Library Voice (blog). January 20, 2016. http://vanmeterlibraryvoice.blogspot.com/2016/01/valentine-ideas-using-digital-tools.html.
Social media post
Note: Awakenings (@awakenings), "Maceo Plex gave us goosebumps...," Facebook, September 12, 2019.
Bibliography:
Awakenings (@awakenings). "Maceo Plex gave us goosebumps...." Facebook, September 12, 2019.
Personal communication (email, text, DM)
Usually cited in-text or in a note only — rarely in the bibliography.
Note: Michele Kirschenbaum, email message to author, January 18, 2016.
Video (YouTube, streaming, etc.)
Note: "Habitats Work in Texas After Hurricane Harvey," Habitat for Humanity, September 11, 2019, YouTube video, 1:35, https://youtu.be/EPPALfWYGRo.
Bibliography:
"Habitats Work in Texas After Hurricane Harvey." Habitat for Humanity. September 11, 2019. YouTube video, 1:35. https://youtu.be/EPPALfWYGRo.
AI-generated content
The 18th edition adds guidance for citing AI tools. Treat AI-generated text as a personal communication in most cases — describe the prompt, tool, and date in the text or a note, and note that AI outputs typically aren't retrievable by readers, so they're not added to the bibliography.
Legal cases, the Bible, and dictionary entries
These are typically cited only in notes, not the bibliography:
- Legal case: Michael Clum v. Jackson National Life Insurance Co., 10-000126-CL (Ingham Cty. 2011).
- Bible: 2 Cor. 11:7 (New Standard Version).
- Dictionary: Encyclopedia Britannica, s.v. "pressure," accessed September 15, 2019, https://www.britannica.com/science/pressure.
Frequently Asked Questions
Is Chicago style still using footnotes?
Yes — the Notes-Bibliography system still relies on footnotes or endnotes plus a full bibliography.
Do I still need "Ibid" in Chicago 18th edition?
No. The 18th edition recommends shortened citations (Last name, page number) instead of "Ibid," even for consecutive references to the same source.
Do I need the city of publication anymore?
No — as of the 18th edition, only the publisher and year are required for books.
Which edition should I use — 17th or 18th?
Use whichever your instructor or publisher requires. Many schools are still transitioning; if you're not told otherwise, the 18th edition (2024) is the current standard.
Generate accurate Chicago citations in seconds with Citation Machine's free Chicago citation generator — updated for the 18th edition.
Written and edited by Arpit Puri, Product Manager of Writing Tools at Chegg.
