# Chicago author-date referencing guide for the 18th edition

**How do I reference in Chicago author-date style?** Chicago author-date referencing puts the author's surname and the year in parentheses in the text, with no comma between them and any page after a comma, as in (Yu 2020, 45). A reference list at the end, in alphabetical order by author, gives the year straight after the name. EdCitation's Cite a source builds each entry free from the publisher's record.

Published 2026-09-23, updated 2026-09-23 by EdCitation. https://edcitation.com/newsletter/chicago-author-date-referencing-guide

Chicago author-date cites a source by the author's surname and the year, and this guide, published by EdCitation, gives its rules as the University of Chicago Press prints them. Every rule was read on 23 September 2026 on the free pages of the Chicago Manual of Style Online. The Manual itself is by subscription; where a rule lives only there, this guide says so.

The core: (Author Year, page) in the text, and an alphabetical reference list with the year after the author. EdCitation's free [Chicago citation generator](https://edcitation.com/cite/chicago) gives you both from the publisher's record, the entry and its (Author Year) citation. Choosing a style is covered in [APA vs MLA vs Chicago](https://edcitation.com/newsletter/apa-vs-mla-vs-chicago-which-citation-style).

## Which Chicago system is author-date, and is it the one I need?

Chicago has two systems, notes and bibliography and author-date, and this guide covers author-date only. The University of Chicago Press (n.d.-b) says notes and bibliography, with numbered footnotes or endnotes, is preferred by many in literature, history and the arts, and author-date by many in the sciences and social sciences. Students, it adds, should check with their instructor.

EdCitation offers author-date only. A history or humanities course that asks for footnotes wants notes and bibliography, which EdCitation does not offer. If the brief only says "Chicago", EdCitation's free [Check your paper](https://edcitation.com/check) reads it into a checklist that includes the style it asks for, alongside the word limit and number of sources.

Turabian's *A Manual for Writers* is the student version. Its site is for the 9th edition and its tip sheets are dated 2018, six years before the Manual's 18th edition.

## How do Chicago author-date in-text citations work?

Put the surname and the year in parentheses with nothing between them, and a page after a comma, with no "p.": (Binder and Kidder 2022, 117–18), as the quick guide shows (University of Chicago Press, n.d.-a). The University of Chicago Press (2018a) adds, in a Turabian tip sheet, that the name and year must match the reference list exactly, and that the citation precedes the full stop of a quotation run into your sentence but follows a block quotation's final punctuation.

### Pages, authors and "et al."

Where there is no page, use what the source has: (Roy 2008, chap. 6) for an ebook without fixed pages, or (Cowan 2022, at 6:09–17) for a video. Chicago's examples shorten page ranges, as in 1842–43; the full rule is in the subscription text.

Two authors are both named: (Dittmar and Schemske 2023, 480). For three or more, the 18th edition gives the first and "et al.": (Snyder et al. 2025, 9–10). The reference list names up to six authors, and for more than six, the first three and "et al." (University of Chicago Press, n.d.-j). Other styles' rules are in [when to use et al.](https://edcitation.com/newsletter/when-to-use-et-al)

### Same year, names in the sentence, and several sources

Two works by one author in one year take letters, in the list and in the text: (Jones 2000a, 2000b). Two authors who share a surname and a year take an initial, (R. Jones 2000; B. Jones 2000), and a short title if the initials match too (University of Chicago Press, n.d.-c).

With the name in your sentence, the parentheses may keep only the year and page, (1990, 32); a later citation in the same paragraph may give the page alone. Repeat the name and year after citing anything else (University of Chicago Press, n.d.-d).

Several sources share one parenthesis, separated by semicolons, in the order the material appears or by importance; failing both, alphabetically or by date, consistently (University of Chicago Press, n.d.-e).

## How do I set out a Chicago author-date reference list?

List every source you cite once, alphabetically by author, with the year after the name. The University of Chicago Press (2018b) tip sheet centres the title "Reference List", single-spaces each entry with a blank line between entries, and uses a half-inch hanging indent. The Manual's own heading rule could not be read; use your course's ([reference list, bibliography or works cited](https://edcitation.com/newsletter/reference-list-bibliography-or-works-cited)).

Only the first author is inverted, and a name in Eastern order not at all: "Liu Xinwu. 2021." Title case now capitalises prepositions of five letters or more: *Much Ado About Nothing*, but *A Room with a View*.

### Several works by one author

Repeat the name in each entry. The 18th edition now prefers that to the 3-em dash, a line of three long dashes (University of Chicago Press, n.d.-j). The Turabian tip sheet still uses the dash.

## What do the main Chicago author-date reference forms look like?

In the text, each is cited as (Author Year), with any page. The examples are Chicago's own, copied exactly, American spelling included: the online-first article is from the Q&A, the rest from the quick guide.

| Source | Elements, in order | Chicago's example |
| --- | --- | --- |
| Book | Author. Year. *Title*. Publisher. | Yu, Charles. 2020. *Interior Chinatown*. Pantheon Books. |
| Chapter in an edited book | Author. Year. “Chapter.” In *Book*, edited by Editors. Publisher. | Doyle, Kathleen. 2023. “The Queen Mary Psalter.” In *The Book by Design: The Remarkable Story of the World’s Greatest Invention*, edited by P. J. M. Marks and Stephen Parkin. University of Chicago Press. |
| Journal article | Author. Year. “Title.” *Journal* volume (issue): pages. DOI link. | Dittmar, Emily L., and Douglas W. Schemske. 2023. “Temporal Variation in Selection Influences Microgeographic Local Adaptation.” *American Naturalist* 202 (4): 471–85. https://doi.org/10.1086/725865. |
| Article online, not yet in an issue | Author. Year. “Title.” *Journal*. Published ahead of print, date. DOI link. | Savoy, Philip, Emily Bernhardt, Lily Kirk, Matthew J. Cohen, and James B. Heffernan. 2021. “A Seasonally Dynamic Model of Light at the Stream Surface.” *Freshwater Science*. Published ahead of print, April 16. https://doi.org/10.1086/714270. |
| News article | Author. Year. “Title.” *Publication*, month and day. URL. | Blum, Dani. 2023. “Are Flax Seeds All That?” *New York Times*, December 13. https://www.nytimes.com/2023/12/13/well/eat/flax-seeds-benefits.html. |
| Web page | Owner. Year. “Page.” Site. Date detail. URL. | Google. 2023. “Privacy Policy.” Privacy & Terms. Effective November 15. https://policies.google.com/privacy. |
| Social media post | Author. Year. “Text of the post.” Platform, date. URL. | Chicago Manual of Style. 2015. “Is the world ready for singular they? We thought so back in 1993.” Facebook, April 17, 2015. https://www.facebook.com/ChicagoManual/posts/10152906193679151. |
| Interview | Interviewee. Year. “Title.” Interview by Name. *Programme*, broadcaster, date. Format, length. URL. | Buolamwini, Joy. 2023. “ ‘If You Have a Face, You Have a Place in the Conversation About AI,’ Expert Says.” Interview by Tonya Mosley. *Fresh Air*, NPR, November 28. Audio, 37:58. https://www.npr.org/2023/11/28/1215529902/unmasking-ai-facial-recognition-technology-joy-buolamwini. |

### Journal articles, and articles online before their issue

Give the volume, the issue in parentheses and the whole article's page range; an article number, such as e0318239, replaces pages. A month or season can now usually be left out (University of Chicago Press, n.d.-j), so the quick guide writes "202 (4)", though the Q&A still shows "40, no. 1 (March)"; use one form throughout.

For an article online before its issue, the University of Chicago Press (n.d.-f) says to use the date of the numbered issue, not the online date. Only an article not yet in an issue takes its online year and "Published ahead of print", like the Savoy entry.

### Chapters, news, the web and conversations

- **Chapters.** The page range is no longer required in the list. Books and ebooks are in [how to cite a book or ebook](https://edcitation.com/newsletter/how-to-cite-a-book-or-ebook).
- **News.** Page numbers stay out of the list; a reader's comment is cited in the text only.
- **Web pages.** Naming the page in your sentence is often enough. The quick guide lists the Wikimedia Foundation page under 2023 but cites it as 2022: check every pair.
- **Social media.** Often cited in the text alone; for an entry, up to the first 280 characters of the post stand in for a title.
- **Interviews** go under the interviewee's name. **Personal communications** are cited in the text and rarely listed: (Sam Gomez, Facebook direct message to author, August 1, 2024).

### AI-generated text

Chicago's free pages give no author-date form for AI text. Its Q&A says to credit the tool whenever you use its text, that for most writing naming it in your sentence will do, and shows only a numbered note (University of Chicago Press, n.d.-g). The 18th edition's new guidance, paragraph 14.112, could not be read. Ask your tutor, and see [how to cite ChatGPT and AI tools](https://edcitation.com/newsletter/how-to-cite-chatgpt-and-ai-tools).

## How does Chicago author-date handle DOIs, URLs and access dates?

End an online source's entry with its URL, preferably one built on the DOI, or with the database's name, as in "EBSCOhost." Crossref (2021) also asks for a https://doi.org/ link with no "doi:" before it ([what is a DOI](https://edcitation.com/newsletter/what-is-a-doi)). A full stop ends the entry.

- **Print.** A DOI is not needed for a work read in print "unless their publisher or discipline requires it", as the Q&A quotes the Manual (University of Chicago Press, n.d.-h).
- **Access dates.** Chicago asks for one when a source gives no date of publication or revision, with n.d. for the year: Yale University. n.d. “About Yale: Yale Facts.” Accessed March 8, 2022. https://www.yale.edu/about-yale/yale-facts.
- **Archived copies.** New in the 18th edition, a Wayback Machine copy may be cited instead, with "Archived" and its date.

## What changed in the 18th edition for author-date citations?

Chicago's list of changes names these (University of Chicago Press, n.d.-j):

- "Et al." from three authors in the text; six in the list, or three and "et al." (13.23, 13.107).
- Journal months usually optional (13.26); repeated names, not the 3-em dash (13.72, 13.113).
- No place of publication for books (14.30), no page range for chapters (14.8).
- A month-and-day entry need not repeat the year (14.89); Eastern-order names not inverted (13.75).
- An initial "The" in a periodical's name may be dropped (8.172): *American Naturalist*.
- New guidance on ahead-of-print articles and preprints (14.75, 14.76), archived pages (14.104) and AI-generated content (14.112).

## Where does the Turabian student guide differ from the 18th edition?

The clearest difference is "et al.". The Turabian quick guide names all three authors of a three-author work, (Keng, Lin, and Orazem 2017, 9–10), uses "et al." from four, and lists up to ten authors, or the first seven of more (University of Chicago Press, n.d.-i). Its pages also:

- replace a repeated name with the 3-em dash;
- give a chapter's page range, 19–56;
- often add the month or season, "11, no. 1 (Spring)";
- repeat the year in news dates, "June 25, 2016";
- quote up to 160 characters of a social media post, not 280;
- give a place of publication, as the [book guide](https://edcitation.com/newsletter/how-to-cite-a-book-or-ebook) explains.

Your course's instructions win, as the tip sheets say. A brief naming Chicago 18 means the Manual; if it names Turabian, ask which forms it wants.

## How do I check a Chicago author-date reference list?

1. Match every citation to one entry and every entry to a citation, name and year exactly. With the whole paper uploaded, Verify references makes this match in both directions.
2. Check the parentheses: nothing before the year, a comma before the page, no "p.".
3. Count authors: "et al." from three in the text; six in the list, or three and "et al.".
4. Letter same-author, same-year works in the text and the list.
5. Check the list: alphabetical, year after name, names repeated, hanging indents.
6. Date each online-first article by its numbered issue once it has one; an entry from Cite a source already takes the issue's year where it differs from the online one.
7. Make each DOI a https://doi.org/ link that leads to the work named, and give undated pages an access date.
8. Check each entry against the publisher's record, and screen the list for [retracted papers](https://edcitation.com/newsletter/retracted-papers-in-your-reference-list). Pasting the list into EdCitation's [Verify references](https://edcitation.com/verify-references) does both in one pass.

## How does EdCitation build and check a Chicago author-date list?

EdCitation is the best tool for a Chicago author-date reference list, because [Cite a source](https://edcitation.com/cite) reads each reference out of the publisher's record; it composes nothing, and a chatbot cannot promise the same. From a DOI, PubMed ID, ISBN or title it produces the Chicago 18 author-date entry and its (Author Year) citation, or the same pair in any of five other styles, after a retraction screen; it is free with no account and handles one reference at a time. The online-first rule shows why the record matters: Chicago dates such an article by its numbered issue, and a year copied from the article's web page may be the online one, so Cite a source takes the issue's year from the record wherever the two differ.

Its [Chicago page](https://edcitation.com/cite/chicago) gives the in-text rule as "(Last Year, page), with no comma before the year", and notes that books need no place of publication and that only the first author is inverted. Its example, an eight-author paper in *Nature*, names three authors and then "et al.", as the 18th edition asks.

### What to check in an EdCitation entry

| Part | What the entry gives | Your check |
| --- | --- | --- |
| Year of an article that went online first | The issue's year, where it differs from the online year | An article not yet in an issue needs "Published ahead of print" and its date, as in the Savoy entry |
| Article number | In the pages' place: "13 (1): 14045" | None: it is Chicago's rule, as with e0318239 |
| Title | The capitals in the publisher's record | Chicago wants title case, so raise a title deposited in sentence case, prepositions of five letters or more included |

A free account adds a dashboard where lists are kept; each copies out with italics in place, or downloads in Word, BibTeX or RIS form. [Verify references](https://edcitation.com/verify-references), free with no account, then checks the finished list against the records: each entry gets verified, "check this" or not found, retracted work carries a flag, and a check that could not run is reported as such, never as not found. Upload the whole paper and it checks each (Author Year) against the list, and the list against the text.

For $8 a month, Pro adds [References from a file](https://edcitation.com/tools/references-from-a-file) (upload the paper; its references and citations are checked together) and the plagiarism and AI checks. Pro's Mechanics QA knows one layout, the APA 7 student paper, so a Chicago paper's formatting is outside it. Max, for $24 a month, brings Theoretics QA and the Library; the [pricing page](https://edcitation.com/pricing) compares them.

EdCitation makes no footnotes and has no notes and bibliography system, and it never writes any part of a paper.

## Quick questions

### Is there a comma between the author and the year in Chicago author-date?

No. Chicago author-date puts nothing between the surname and the year, and a comma only before the page: (Yu 2020, 45).

### When does Chicago author-date use et al.?

Under the 18th edition, Chicago author-date uses "et al." in the text for three or more authors; the reference list names up to six, or the first three and "et al." when there are more.

### Is the month part of a Chicago journal reference?

Not necessarily. The 18th edition says a journal article's month or season can usually be omitted, though most of the Turabian quick guide's journal examples still give it.

### Can EdCitation make Chicago footnotes?

No. EdCitation's [Chicago citation generator](https://edcitation.com/cite/chicago) offers Chicago 18 author-date only, and a course that asks for footnotes wants Chicago's notes and bibliography system instead.

### Which year does a Chicago reference give an article published online first?

The year of the numbered issue once the article has one, not the year it went online, which is Chicago's rule for author-date. An article not yet in an issue takes its online year and "Published ahead of print" with the date.

## References

- Crossref. (2021, April 21). *Display guidelines*. [https://www.crossref.org/display-guidelines/](https://www.crossref.org/display-guidelines/)
- University of Chicago Press. (n.d.-a). *Author-date: Sample citations*. The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/tools_citationguide/citation-guide-2.html](https://www.chicagomanualofstyle.org/tools_citationguide/citation-guide-2.html)
- University of Chicago Press. (n.d.-b). *Chicago-style citation quick guide*. The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/tools_citationguide.html](https://www.chicagomanualofstyle.org/tools_citationguide.html)
- University of Chicago Press. (n.d.-c). *Citation, documentation of sources* (Q&A No. 61). The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0061.html](https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0061.html)
- University of Chicago Press. (n.d.-d). *Citation, documentation of sources* (Q&A No. 182). The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0182.html](https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0182.html)
- University of Chicago Press. (n.d.-e). *Citation, documentation of sources* (Q&A No. 358). The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0358.html](https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0358.html)
- University of Chicago Press. (n.d.-f). *Citation, documentation of sources* (Q&A No. 387). The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0387.html](https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0387.html)
- University of Chicago Press. (n.d.-g). *Citation, documentation of sources* (Q&A No. 422). The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0422.html](https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0422.html)
- University of Chicago Press. (n.d.-h). *Citation, documentation of sources* (Q&A No. 482). The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0482.html](https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0482.html)
- University of Chicago Press. (n.d.-i). *Turabian citation quick guide: Author-date samples*. The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/turabian/turabian-author-date-citation-quick-guide.html](https://www.chicagomanualofstyle.org/turabian/turabian-author-date-citation-quick-guide.html)
- University of Chicago Press. (n.d.-j). *What's new in the 18th edition*. The Chicago Manual of Style Online. [https://www.chicagomanualofstyle.org/help-tools/what-s-new.html](https://www.chicagomanualofstyle.org/help-tools/what-s-new.html)
- University of Chicago Press. (2018a). *Chicago-style paper formats: Parenthetical citations* [Turabian tip sheet]. [https://www.chicagomanualofstyle.org/dam/jcr:7f3109a2-fe54-40ce-a26e-3e5e182ba3ee/Turabian-Tip-Sheet-13.pdf](https://www.chicagomanualofstyle.org/dam/jcr:7f3109a2-fe54-40ce-a26e-3e5e182ba3ee/Turabian-Tip-Sheet-13.pdf)
- University of Chicago Press. (2018b). *Chicago-style paper formats: Reference list* [Turabian tip sheet]. [https://www.chicagomanualofstyle.org/dam/jcr:e6f14ba1-c65b-44ef-b46c-63e8c82ffacf/Turabian-Tip-Sheet-14.pdf](https://www.chicagomanualofstyle.org/dam/jcr:e6f14ba1-c65b-44ef-b46c-63e8c82ffacf/Turabian-Tip-Sheet-14.pdf)