Chicago Style has two systems for citing sources:
- Notes and Bibliography, which works with footnotes or endnotes, often accompanied by a bibliography. This system is mainly used in the humanities.
- Author-Date References, which works with parenthetical citations (reporting only the author and publication date). In-text citations are always accompanied by a reference list. This system is mostly used in sciences and social sciences.
Chicago Style Citation: Notes and Bibliography
Footnotes vs. endnotes
Footnotes appear at the bottom of a page, while endnotes appear at the end of a chapter, section or work. Most universities and journals clearly indicate their preference. The citation format is identical; only the location is different.
The notes correspond with superscript numbers in the running text. These numbers are placed at the end of a sentence or clause, after the punctuation mark.
- Smith states that “retaining customers is difficult, especially online.”1
Microsoft Word can automatically link the superscript number and notes. Read more about how to insert footnotes.
Full notes vs. short notes
Footnotes and endnotes can take the form of full notes or shortened notes. Short notes help avoid cluttered pages and should be used in two situations:
- When the text includes a bibliography (which already lists the full source).
- When you cite the same source again after the first full note.
Chicago style citation examples
A Chicago footnote citation usually contains the author name(s) and title (in title case). A full note also contains the date and other publication details specific to each source type. Elements are separated with commas, and the citation ends with a period.
Navigate through the Chicago citation examples using the tabs below.
|Full note||Author first name last name, Book Title: Subtitle, edition. (Place of publication: Publisher, Year), page numbers, URL.|
|Short note||Author last name, Shortened Book Title, page number(s).|
Notes: Edition and page number(s) are optional and should only be included if relevant. The edition is always abbreviated (e.g. 2nd ed. or rev. ed.). Only include the URL for books you consulted online.
|Full note||Author first name last name, “Chapter Title,” in Book Title: Subtitle, ed. Editor first name last name (Place of publication: Publisher, Year), page number(s).|
|Short note||Author last name, “Shortened Book Chapter Title,” page number(s).|
Note: Begin the citation with the author of the chapter. The editor who compiled the book is listed after the book title.
|Full note||Author first name last name, “Article Title,” Journal Name Volume, Issue number (Year): page number, DOI or URL.|
|Short note||Author last name, “Shortened Journal Article Title,” page number(s).|
Note: The page (range) in the notes indicates the page or pages containing the relevant information, not the page range of the whole journal article.
|Full note||Author first name last name, “Page Title,” Website Title, publication date, URL.|
|Short note||Author last name, “Shortened Website Title.”|
Notes: If the author is unknown, use the website name instead (don’t list the website title after the page title). If the publication date is unknown, include the date you accessed the information (e.g. accessed on March 12, 2019). Titles longer than four words should be shortened when using a short note.
Chicago Style Citation: Author-Date Reference
Chicago’s Author-Date system, most often used in the (social) sciences, works with parenthetical citations in the text. Chicago in-text citations include the author’s last name, publication date and, if relevant, page numbers. The in-text citations are always accompanied by a bibliography.
The in-text citation is placed at the end of the sentence or paragraph that is quoted or paraphrased. However, you may be a little more flexible by integrating the citation in the sentence, as can be seen in the examples below.
- In a recent study (Datta 2015, 220) …
- Datta (2015, 220) found in a recent study …
- In recent studies … (Datta 2015, 220; Smith 2011, 58–77).
The in-text citation is the same for each source type, and there is no difference between a first citation and a subsequent citation. Sources with multiple authors are cited slightly differently.
In-text citations can be combined by separating them with a semicolon (see the last example). It is common practice to sort the sources alphabetically (first Datta, then Smith).
Missing data in notes and in-text citations
No publication date
For sources without a publication date or latest revision date, use “n.d.” (no date) instead. If the source was accessed online, you can add an access date in a full note instead.
- (Sinek, n.d.).
- 1. Simon Sinek, Start with Why (New York: Penguin Books, n.d.), 267–86.
- 2. “Strategic Themes,” Utrecht University, accessed October 3, 2019, https://www.uu.nl/en/research/profile/strategic-themes.
No author/organization as author
If the author of a source is unknown (often the case with internet sources), the organization or association issuing the publication may be listed as the author.
- (Microsoft 2018, 55–8)
- 1. University of Chicago Press, The Chicago Manual of Style, 17th ed. (Chicago: University of Chicago Press, 2017), 791.
- 2. Scribbr, “Detect, Understand and Correct All Plagiarism,” accessed March 12, 2019, https://www.scribbr.com/plagiarism-checker/.
Works explicitly published as “Anonymous” do need to be cited that way e.g. (Anonymous 2016).
No page number
Page numbers need only be included when relevant. If you do want to add a locator to the citation, but your source doesn’t have page numbers, you may also use paragraph, section or chapter numbers, or even section headings if relevant.
- (Smith 2017, para. 2.15)
- 1. Simon Sinek, Start with Why (New York: Penguin Books, 2011), chap. 5.
- (Miller and Johnson 2013, “Methods”)
Multiple authors in notes and in-text citations
Author names should always be listed in the order in which they appear in the source. The names of two authors are separated with “and”. The names of three authors are listed with the final “and” preceded by a serial comma.
- (Datta and Smith 2009, 123)
- (Key, Appleby, and Rosell 2006, 39)
- 1. Timothy J. Key, Paul N. Appleby, and Magdalena S. Rosell, “Health Effects of Vegetarian and Vegan Diets,” Proceedings of the Nutrition Society 65, no. 1 (2006): 39, https://doi.org/10.1079/PNS2005481.
4 or more authors
Sources with more than three authors are shortened. This is the case for notes, in-text citations and in the running text. Only the first author’s last name is included, followed by “et al.” (“and others”). In the bibliography or reference list, all names are included.
- (Johnson et al. 2017)
- Johnson et al. (2017) found in a recent study …
- 1. Covey et al., The 7 Habits of Highly Effective People (New York: Free Press, 1989), 75–89.
Editors and translators as authors
Most of the time, you’ll cite the author of a text, not the editor or translator. However, if you want to cite a whole edited collection or cite a translator’s work, you can use this name in place of the author.
In author-date in-text citations, editors and translators are treated the same as regular authors with no added information. However, in notes and in the bibliography, the role (e.g. “ed.” or “trans.”) is added.
- (Egan 2014, 100)
- 1. Jennifer Egan, ed., The Best American Short Stories, 2015 (Boston: Houghton Mifflin Harcourt, 2014), 100.
Chicago Style Bibliography or Reference List
The bibliography, known as the reference list in author-date style, is an alphabetized list of all sources cited in the text. The bibliography or reference list is placed on a separate page before the appendices.
A reference list is required when using Chicago author-date references. When using Chicago style footnotes or endnotes, a bibliography is not required, but recommended. If you include a bibliography, you can use shortened notes for all in-text citations, which saves space and improves readability.
Bibliography vs. Reference List
The format of a full reference is almost identical in the two systems. The only difference between a bibliography entry and a reference list entry is the location of the publication year. In an author-date style reference list, the year appears directly after the author. In the notes and bibliography system, the year appears after the publisher.
The Chicago book citation example below shows the full reference for both systems, with the publication year highlighted.
Reference List (Author-Date system)
- Covey, Stephen. 1989. The 7 Habits of Highly Effective People. New York: Free Press.
Bibliography (Notes and Bibliography system)
- Covey, Stephen. The 7 Habits of Highly Effective People. New York: Free Press, 1989.
Multiple authors in the bibliography
In the bibliography or reference list, up to 10 authors of a source are included. If there are more than 10, list the first seven followed by “et al.”
|Format||Author last name, first name. Book Title: Subtitle. edition. Place of publication: Publisher, Year. URL.|
|Bibliography||Covey, Stephen. The 7 Habits of Highly Effective People. New York: Free Press, 1989.|
Notes: Page numbers are not included in the bibliography. If the author has the role of editor or translator, add “, ed.” or “, trans.” after the author name(s), e.g. Covey, Stephen, trans. The edition is always abbreviated (e.g. 2nd ed. or rev. ed.). Only include the URL for books you consulted online.
|Format||Author last name, first name. “Chapter Title.” In Book Title: Subtitle, edited by Editor first name last name, page range. Place of publication: Publisher, Year.|
|Bibliography||Stewart, Bob. “Wag of the Tail: Reflecting on Pet Ownership.” In Enriching Our Lives with Animals, edited by John Jaimeson, 220–90. Toronto: Petlove Press, 2007.|
Note: Begin the citation with the author of the chapter. The editor who compiled the book is listed after the book title and before the page range of the cited chapter.
|Format||Author last name, first name. “Article Title.” Journal Name Volume, Issue number (Publication date): Page range. DOI or URL.|
|Bibliography||Datta, Hannes. “The Challenge of Retaining Customers Acquired with Free Trials.” Journal of Marketing Research 52, no. 52 (April 2015): 217–34. www.jstor.org/stable/43832354.|
Notes: The page numbers in the reference refer to the page range of the whole article.
|Format||Author last name, first name. “Page Title,” Website Name. Publication date. URL.|
|Bibliography||Gahan, Courtney. “How to Paraphrase Sources.” Scribbr. Last updated August 26, 2019. https://www.scribbr.com/citing-sources/how-to-paraphrase/.|
Notes: If the publication date is unknown, the access date is added instead, e.g. (Accessed June 12, 2017.) If the author is unknown, list the website name as author, and don’t repeat it later in the citation.
Arrangement of reference entries
Sources in the bibliography or reference list are ordered alphabetically by the authors’ last names. For sources without an author, alphabetize by the work’s title, ignoring articles (“a”, “an”, “the”).
Multiple works from the same author
If you include multiple works from the same author, only list the author name in the first entry. In subsequent entries you start the source with three em dashes, followed by the work’s title.
- Covey, Stephen. The 7 Habits of Highly Effective People. New York: Free Press, 1989.
———. Principle-Centered Leadership. New Jersey: John Wiley & Sons, 1992.