Chicago style footnotes use superscript numbers in the body of your text that point to numbered notes at the bottom of the page, where you provide full source details. The system is straightforward once you learn the order of elements for each source type and understand how citations change after the first reference. Here’s how to format them correctly.
How Footnotes Work in Your Paper
Every time you quote, paraphrase, or reference a source, place a superscript number at the end of the relevant sentence or clause, after any punctuation. The numbers run sequentially through your entire paper: 1, 2, 3, and so on. Each number corresponds to a note at the bottom of that page containing the citation.
Indent the first line of each footnote a half inch, the same as a paragraph in your main text. You have two options for the note number itself: use superscript followed by a space (no period), or use regular-sized text followed by a period and a space. Either format is acceptable as long as you’re consistent. The note text that follows uses regular text or a slightly smaller font than your body copy.
Your First Citation of a Source
The first time you cite any source, provide the full citation with all relevant details: the author’s full name, the title, publication facts, and a page number if applicable. If your paper includes a bibliography, some instructors allow slightly abbreviated first notes, but the safest approach is a complete citation every time a source appears for the first time.
The general pattern for a first footnote is: Note number. Author First Name Last Name, Title (Publisher, Year), page number. The specifics shift depending on the source type, so the next sections break down the most common ones.
Books
Book footnotes are the simplest form. List the author’s name in normal order (first name first), the book title in italics, then the publisher and year in parentheses, followed by the page number. A place of publication is no longer required for books.
Here’s what a book footnote looks like:
- 1. Charles Yu, Interior Chinatown (Pantheon Books, 2020), 45.
For a book with two authors, list both names separated by “and.” For three or more authors, list the first author followed by “et al.” in the footnote.
Journal Articles
Journal article footnotes include the author’s name, the article title in quotation marks, the journal title in italics, the volume number, the issue number, the year, and the specific page or pages you’re citing. If you accessed the article online, add a URL at the end, preferably one based on a DOI (a permanent digital link assigned to the article).
Here’s the format in practice:
- 1. Hyeyoung Kwon, “Inclusion Work: Children of Immigrants Claiming Membership in Everyday Life,” American Journal of Sociology 127, no. 6 (2022): 1842–43, https://doi.org/10.1086/720277.
Notice the punctuation pattern: a comma after the author’s name, quotation marks around the article title, a comma after the journal title, and a colon before the page numbers. The volume and issue are written as “127, no. 6” with the year in parentheses. These details are easy to miss, so double-check them before submitting.
Websites and Other Online Sources
For a web page, the footnote typically includes the author (if known), the page or article title in quotation marks, the name of the website in italics, the publication or last-modified date, and the URL. If no author is listed, start with the title. If no date is available, include an access date instead so the reader knows when the information was current.
A basic web source footnote follows this pattern:
- 1. Author First Name Last Name, “Title of Page,” Website Name, Month Day, Year, URL.
Shortened Notes for Repeat Citations
After you’ve given the full citation once, every subsequent reference to the same source uses a shortened note. The shortened form includes only the author’s last name, a shortened version of the title, and the page number.
If the full first note was:
- 1. Charles Yu, Interior Chinatown (Pantheon Books, 2020), 45.
A later reference to the same book would look like:
- 5. Yu, Interior Chinatown, 78.
You can shorten long titles to a few key words. The Channels of Student Activism: How the Left and Right Are Winning (and Losing) in Campus Politics Today could become simply Channels of Student Activism. Keep enough words that the reader can identify which source you mean.
When to Use “Ibid.”
“Ibid.” (from the Latin for “in the same place”) refers the reader back to the source in the immediately preceding note. If note 3 cites a book and note 4 cites the same book, note 4 can simply say “Ibid., 52” (with the new page number) or just “Ibid.” if the page is the same.
Two rules govern its use. First, “ibid.” can only refer to the note directly before it. You cannot use it to point back to note 1 from note 5 if notes 2 through 4 cited other sources. Second, the preceding note must contain only one citation. If note 3 cited two different sources, note 4 cannot use “ibid.” because the reader wouldn’t know which source you mean. In those situations, use a shortened note instead.
The Chicago Manual of Style now prefers shortened citations over “ibid.” in most cases. Shortened notes are easier for readers to follow, especially in papers with many sources, and they remain clear even if you later add or rearrange notes during editing. If your instructor or publisher hasn’t specified a preference, shortened notes are the safer choice.
Notes vs. Bibliography Entries
Footnotes and bibliography entries contain the same information but are formatted differently. The key differences to keep in mind:
- Author name order. Footnotes list names in normal order (First Last). Bibliography entries invert the first author’s name (Last, First) for alphabetical sorting.
- Punctuation. Footnotes separate elements with commas and put publication details in parentheses. Bibliography entries use periods between major elements and omit the parentheses around publication facts.
- Page numbers. Footnotes cite the specific page you’re referencing. Bibliography entries for journal articles give the full page range of the article.
Compare a journal article in both formats. The footnote:
- 1. Hyeyoung Kwon, “Inclusion Work,” American Journal of Sociology 127, no. 6 (2022): 1842–43.
The bibliography entry for the same article:
- Kwon, Hyeyoung. “Inclusion Work: Children of Immigrants Claiming Membership in Everyday Life.” American Journal of Sociology 127, no. 6 (2022): 1818–59. https://doi.org/10.1086/720277.
Inserting Footnotes in Your Document
In Microsoft Word, place your cursor where the superscript number should appear, then go to the References tab and click “Insert Footnote.” Word automatically numbers the note, jumps to the bottom of the page, and creates a space for you to type the citation. Google Docs works the same way through Insert > Footnote. Both programs handle renumbering automatically if you add or delete a note later.
Place the superscript number after the period, comma, or other punctuation mark at the end of the sentence or clause containing the referenced material. The only exception is a dash, where the note number goes before it. Avoid placing note numbers in the middle of a sentence unless you need to attribute a specific clause to a different source than the rest of the sentence.