How and when to use et al.
“Et al.” is short for the Latin term “et alia,” meaning “and others.” It is used in academic citations when referring to a source with multiple authors:
Different citation styles have different rules for when to use “et al.” Below, we explain the rules for APA, MLA, and Chicago.
Common mistakes
There are a couple of common mistakes to watch out for when using “et al.”
Punctuation
The “al” in “et al.” is always followed by a period. This is because the term is an abbreviation of the Latin phrase “et alia”—the period indicates that it is an abbreviation:
- et al
- et. al
- et. al.
- et al.
“Et al.” may be directly followed by other punctuation where necessary, but the period always comes first:
When “et al.” comes right at the end of a sentence, only one period is used:
Et al. vs. etc.
“Et al.” should not be confused with “etc.”; it is used for lists of people, whereas “etc.” is used for lists of things and concepts:
Using et al. in APA Style
In APA Style in-text citations, when a source has two authors, list both. When there are three or more authors, cite the first author followed by “et al.”
| Number of authors | In-text citation |
|---|---|
| 1–2 authors | (Anderson & Singh, 2018) |
| 3+ authors | (McDonnell et al., 2019) |
APA does not recommend using “et al.” in the reference list. Instead, list up to 20 authors in full. When a source has more than 20 authors, list the first 19, then an ellipsis (…), then the final name:
6th edition rules
The rules above apply to the 7th edition of the APA manual. If you’re instructed to follow the 6th edition, the use of “et al.” is slightly different.
For sources with three to five authors, list all the authors the first time, and use “et al.” only in subsequent citations. For sources with six or more authors, use “et al.” from the first citation.
| Number of authors | First citation | Subsequent citations |
|---|---|---|
| 3–5 authors | (Smith, Sanchez, Davies, Baldwin, & Caulfield, 2016) | (Smith et al., 2016) |
| 6+ authors | (McDonnell et al., 2016) | (McDonnell et al., 2016) |
Using et al. in MLA style
In MLA style, always use “et al.” for sources with three or more authors. This applies both to in-text citations and in the Works Cited list.
| Number of authors | In-text citation example | Works cited example |
|---|---|---|
| 1–2 authors | (Smith and Davies) | Smith, Joshua, and Robert Davies. … |
| 3+ authors | (McDonnell et al.) | McDonnell, Frederick, et al. … |
Using et al. in Chicago style
Chicago style has two systems of citation: notes and bibliography, and author-date style. The use of “et al.” is the same in both styles.
For sources with one, two, or three authors, list all author names in your in-text citations (whether footnotes or author-date). For sources with four or more authors, use the first name followed by “et al.”
| Number of authors | Footnote example | Author-date example |
|---|---|---|
| 1–3 authors | 1. Joshua Smith and Robert Davies,… | (Smith and Davies 2019) |
| 3+ authors | 2. James Simpson et al., … | Simpson et al., … |
In your Chicago style reference list or bibliography, list up to 10 authors. If a source has more than 10 authors, list the first seven followed by “et al.”:
