Chicago Author-Date Style | A Complete Guide to Citing Sources

The Chicago Manual of Style provides guidelines for two styles of source citation: notes and bibliography and author-date. Author-date style is the preferred option in the sciences and social sciences.

In author-date style, an in-text citation consists of the author’s name, the publication year, and (if relevant) a page number. Each citation must correspond to an entry in the reference list at the end of your paper, where you give full details of the source.

Chicago author-date style
Chicago author-date citation (McGuire 2016, 22)
Chicago reference entry McGuire, Ian. 2016. The North Water. London: Simon & Schuster.

Using author-date in-text citations

In Chicago author-date style, you cite sources in parentheses in the text. The citation includes the author’s last name followed by the year of publication, with no punctuation in between:

(Smith 2012)

If you refer to a specific part of the text (particularly when quoting or paraphrasing), you should also add a page number or page range to direct the reader to the relevant passage. The page number appears after a comma:

(Smith 2012, 21–22)

Placement of in-text citations

A citation usually appears at the end of the relevant clause, sentence or quotation, before any concluding punctuation. If multiple citations are needed at the same point, they should appear in the same set of parentheses separated by a semicolon:

Previous researchers have argued that the evidence is insufficient to confirm a correlation (Smith 2012; Johnson 2015), but new evidence suggests this consensus may be mistaken (McDonald 2018).

If the researcher’s name is already mentioned in the text, the citation should appear straight after it and include only the date. If quoting, add a page number directly after the quote:

Smith (2012) argues that there is reason to believe this method has “great potential” (31). However, Johnson’s (2015) experiment fails to bear out this assertion.

Creating a reference list

The reference list appears at the end of your paper, and provides more detailed information about the sources you cited.

Each entry in the reference list also begins with the author’s last name and the publication date, so that your reader can easily find any source they encounter in the text:

Smith, James. 2012. Example Book. New York: Norton.

Your reference list is usually titled “References” or “Works Cited.” It is alphabetized by author last name. It is single-spaced, unlike the main text, but a blank line is left between entries.

Entries which extend onto more than one line have a “hanging indent,” which means the second and any subsequent lines are indented:

Garcia Márquez, Gabriel. 1988. Love in the Time of Cholera. Translated by Edith Grossman. London: Cape.

Below is an example of what a typical reference list looks like:

Chicago reference list

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Format of reference list entries

The format of the entry varies somewhat according to what type of source you’re citing. Examples for various source types are given below.

Book citation

Book citations include the title in italics, the place of publication and the publisher. If the book gives an edition on the title page, include this. Add the names of any editors and translators, and add a URL or e-book format if you consulted a digital version.

Author last name, first name. Year. Book Title. Edition. Place of publication: Publisher. URL.
García Márquez, Gabriel. 1988. Love in the Time of Cholera. Translated by Edith Grossman. London: Cape.


Book chapter citation

To cite a chapter from an edited collection, include the chapter title in quotation marks, the page range where the chapter appears, and the editor(s) of the book.

Author last name, first name. Year. “Chapter Title.” In Book Title, edited by Editor first name last name, page range. Place of publication: Publisher.
Stewart, Bob. 2007. “Wag of the Tail: Reflecting on Pet Ownership.” In Enriching Our Lives with Animals, edited by John Jaimeson, 220–90. Toronto: Petlove Press.


Journal article citation

Journal article entries include the volume and issue number, as well as a more specific publication date and a page range showing where the article appears in the journal. If accessed online, add a digital object identifier (DOI) or a URL.

Author last name, first name. Year. “Article Title.” Journal Name Volume, Issue number (Publication date): Page range. DOI or URL.
Andreff, Wladimir, and Paul D. Staudohar. 2000. “The Evolving European Model of Professional Sports Finance.” Journal of Sports Economics 1, no. 3 (August): 257–276.


Website citation

For web pages and online articles, put the page or article title in quotation marks, followed by the name of the website. If there is no publication date, replace the year with “n.d.” and give the date on which you accessed the page.

Author last name, first name. Year. “Page Title.” Website Name. Access/revision date. URL.
McCombes, Shona. 2019. “Creating an MLA Heading.” Scribbr. Updated September 12, 2019.


Variations on the format of Chicago author-date citations

The format of in-text citations and reference list entries can vary to accommodate circumstances like multiple authors, multiple publications by the same author in one year, and missing information.

Citing a source with multiple authors

When there are multiple authors, list their names in the same order as they appear in the source.

When a source has two or three authors, include the names of all the authors in your in-text citation. For sources with four or more authors, use the name of the first author followed by “et al.

Multiple authors in in-text citations
2 authors (Grazer and Fishman 2015)
3 authors (Berkman, Bauer, and Nold 2011)
4+ authors (Johnson et al. 2016)

In the reference list, up to ten authors are listed. Alphabetize based on the first author’s last name. The other names are not inverted:

Gmuca, Natalia V., Linnea E. Pearson, Jennifer M. Burns, and Heather E. M. Liwanag. 2015. “The Fat and the Furriest: Morphological Changes in Harp Seal Fur with Ontogeny.” Physiological and Biochemical Zoology 88, no. 2 (March/April): 158–66.

In the case of a source with eleven or more authors, list the first seven in the reference list, followed by “et al.”

Citing multiple sources with the same author and year

If you cite multiple sources by the same author that were published in the same year, it’s important to use another identifier to distinguish between them in the text.

In cases like this, list the sources in alphabetical order by title in your reference list, and add a letter after the year of each one: a, b, c…

Smith, James. 2012a. “Example Article.” Science Journal 2, no. 1 (March): 211–37.

Smith, James. 2012b. Example Book. New York: Norton.

List the same letters after the in-text citations – which may appear in the text in a different order:

(Smith 2012b)

(Smith 2012a)

Citing sources with missing information

Sometimes not all the information required for a citation will be available.

If you need to cite a source with no publication date, write “n.d.” (“no date”) in place of the date in your in-text citation and in your reference list:

(Smith n.d.)

Smith, James. n.d. Example Book. New York: Norton.

If you need to cite a source with no author, there are a couple of scenarios. If you’re dealing with a source issued by an organization without a specific author listed (for example, a press release or pamphlet), you can list the organization as the author:

(University of Glasgow 2019)

University of Glasgow. 2019. “Colombian River Guardians Rally Support in Scotland.” October 14, 2019.

If this doesn’t work for your source, begin your reference list entry with the title instead, alphabetized according to the first word of the title (ignoring articles):

The Example Book: A Book of Examples. 2012. New York: Norton.

Here the entry would be alphabetized under “E”, not “T”, because the article is ignored for alphabetization.

For an in-text citation, use the title. If the title is longer than four words, use a shortened version of it starting with the first word (excluding articles):

(Example Book 2012)

Note that if a source is explicitly attributed to “Anonymous,” this word should simply be used as a name:

(Anonymous 2011)

Frequently asked questions about Chicago author-date style

When should I include page numbers in Chicago style citations?

Page numbers should be included in your Chicago in-text citations when:

  • You’re quoting from the text.
  • You’re paraphrasing a particular passage.
  • You’re referring to information from a specific section.

When you’re referring to the overall argument or general content of a source, it’s unnecessary to include page numbers.

When should I use “et al.” in Chicago style citations?

When a source has four or more authors, your in-text citation or Chicago footnote should give only the first author’s name followed by “et al.” (Latin for “and others”). This makes your citations more concise.

In your bibliography or reference list, when a source has more than 10 authors, list the first seven followed by “et al.” Otherwise, list every author.

What is the difference between a Chicago reference list and a bibliography?

Both present the exact same information; the only difference is the placement of the year in source citations:

  • In a reference list entry, the publication year appears directly after the author’s name.
  • In a bibliography entry, the year appears near the end of the entry (the exact placement depends on the source type).

There are also other types of bibliography that work as stand-alone texts, such as a Chicago annotated bibliography.

Do I have to include a bibliography or reference list?

In Chicago author-date style, your text must include a reference list. It appears at the end of your paper and gives full details of every source you cited.

In notes and bibliography style, you use Chicago style footnotes to cite sources; a bibliography is optional but recommended. If you don’t include one, be sure to use a full note for the first citation of each source.

Is this article helpful?
Jack Caulfield

Jack is a Brit based in Amsterdam, with an MA in comparative literature. He writes for Scribbr and reads a lot of books in his spare time.


June 15, 2022 at 2:03 PM


I was wondering, for chicago author-date in-text citation, if I cite the source within one paragraph multiple times, do I still have to always write the whole citation or is it possible to use something like ibid. ?
So instead of always writing (Bilali and Vollhardt 2015, 492) just (ibid, 492)

Thanks in advance


Jack Caulfield
Jack Caulfield (Scribbr Team)
June 16, 2022 at 11:23 AM

Hi Carla,

As far as I can tell, Chicago doesn't mention any way of shortening repeated author-date citations, and they don't mention using ibid. in this context. So I would suggest sticking with the full citation, even though it's a bit repetitive.


March 22, 2022 at 1:19 PM

I'm wondering how to cite several different entries from the same website with no date. Does the a-b-c rule apply then? If so, in-text citations would follow this pattern: (Eurostat n.d.a) ... (Eurostat n.d.b) ... (Eurostat n.d.c) ? Thank you!


Jack Caulfield
Jack Caulfield (Scribbr Team)
March 28, 2022 at 12:55 PM

Hi Paulina,

Yes, that's indeed the correct format if you have multiple sources from the same author with no date.


March 9, 2022 at 9:09 PM


I would like to know if there are any differences between Chicago's Author/Date style and Harvard style.
They appear to be the exact same to me but I'm overlooking something I'd like to know!

Thank you!


Jack Caulfield
Jack Caulfield (Scribbr Team)
March 10, 2022 at 11:06 AM

Hi Venus,

They're certainly similar styles in that they're both 'author-date' approaches to citation. They differ on some of the specifics of how in-text citations and reference list entries are formatted. For instance, where to place commas, whether to use "p." before page numbers, and so on. So they're not the same style, but they certainly have the same basic approach.


December 9, 2021 at 2:04 AM

Hello, I would like to reflect the thoughts of an author in my bachelor thesis. I often mention the name of the author in my text. So I ask myself whether I have to put the year and page number after the author's name every time? Or is it enough if I do that at the end of the content section?

Thanks for your help!


Jack Caulfield
Jack Caulfield (Scribbr Team)
December 13, 2021 at 2:12 PM

Hi Anna,

Whenever you’re paraphrasing or quoting a specific part of the author’s writing (i.e., you’re not just making a broad generalization about them), you should include a citation pointing the reader to the relevant page in the source, yes. One citation at the end of the section isn’t specific enough; for each specific thought you borrow from this author, the reader should know where to look for it in the author’s own work. You don’t have to include a citation literally every time you mention the author’s name, but definitely every time you refer to a specific thought from them. Hope that helps!


November 22, 2021 at 8:16 AM


I would like to know what the format is for the Chicago-author-date style in word for the reference list?

For example,

What should the line spacing be?

I know that the line spacing is single, but I am unsure what the "before" and "after" option should be (should both the number option for "before" and "after" be 0 pt)?

I hope you are able to understand this question!



Jack Caulfield
Jack Caulfield (Scribbr Team)
November 22, 2021 at 12:47 PM

Hi Tim,

Chicago doesn’t give any specific guidance about this issue, but based on the spacing in the example images they show, it seems like the “before” and “after” settings should both be 0.


September 30, 2021 at 12:42 AM

Hi, I would like to know how I should organize multiple works of the same author in one set of brackets with in-text citation. If for example I refer to Jackson 2000 and Jackson 2005? Should it be:
(Jackson 2000 and 2005)
(Jackson 2000; Jackson 2005)


Jack Caulfield
Jack Caulfield (Scribbr Team)
October 4, 2021 at 1:21 PM

Hi Konstantine,

When you cite two works by the same author in the same place, you can just place a semicolon between the two years; you don't need to repeat the author's name: (Jackson 2000; 2005).


May 31, 2021 at 1:21 PM


I would like to know how I should organize multiple sources in one set of brackets with in-text citation. If for example I refer to Bol 2010, Cricket 2008, and Dumbo 2017, should I organize them alphabetically, chronologically, or by relevance?

Thank you!


Jack Caulfield
Jack Caulfield (Scribbr Team)
May 31, 2021 at 3:06 PM

Hi Danique,

In this case, you're free to choose which order to place them in. Chicago suggests alphabetical, chronological, or ordering by importance are all valid approaches; use whichever approach seems most appropriate to you.


May 10, 2021 at 11:40 AM


I was wondering what should I do when citing in author-date Chicago style and writing an additional footnote (to further explain a concept presented in the text), in which I want to cite a book, a website or anything else.

So, how do I cite an additional source in the footnote when using author-date style?

Thanks in advance,


Jack Caulfield
Jack Caulfield (Scribbr Team)
May 10, 2021 at 4:12 PM

Hi Valeria,

To cite a source in author-date style within a footnote, you can just follow the usual style for author-date citations in the main text. For example:

1. As Jane Doe (2021, 289) observes, ". . ."


Frank Meegan
February 2, 2021 at 7:17 AM

I am curious how one references a footnote in a book in a Chicago style Author/Date in-text citation. Do you just put the page of the footnote, or do you do something like, (Latour 2005, 12, n.35)? Thanks for your help!


Jack Caulfield
Jack Caulfield (Scribbr Team)
February 9, 2021 at 4:35 PM

Hi Frank,

The format Chicago recommends for this is indeed to use "n" but without any spaces or punctuation. So to cite note 35 on page 12, you'd write "(Latour 2005, 12n35)". However, they also say that if there's only one note on the page, you can just write "n" without specifying the note number, i.e. "(Latour 2005, 12n)".


October 16, 2020 at 7:04 AM

What if there is no author and no date in intext reference? How to cite?


Shona McCombes
Shona McCombes (Scribbr Team)
October 20, 2020 at 10:38 PM


If there is no individual author listed, but the source was created by a specific organization, cite the organization name as the author. If not, use a shortened version of the title instead.

If there is no publication date, replace in with "n.d." (which stands for "no date") in both your in-text citation and reference list.

Hope that helps!


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