How Do You Use et al. in Citations?

What the abbreviation actually means, and what it does not

Et al. short for the Latin et alii, and others, and it does one job: it stands in for the author names a style does not want you to print. The first author always stays visible, because a reference list without a first name is a reference list nobody can use. The name and the abbreviation form a single unit, so nothing goes between the surname and the abbreviation except a space, and nothing goes between et and al except a thin one. In the body of an APA paper the abbreviation sits inside the parentheses with the year, as in (Erikson et al., 2020), and in a reference list it stands alone after the names that do appear. Check the source's own metadata for the author count before you decide, because the count, not the length of the paper, decides the form.

It is also not a different work. Et al. describes the same source your reader would find under the full author list, and the title, year and publisher stay exactly as they are. This matters when your instructor asks you to locate the source in a database: you look the paper up by title rather than by counting authors, and et al. in a reference entry is a formatting decision rather than a way of identifying a shorter paper. A citation that uses et al. where a full list was required is an incomplete citation, and a grader who checks the original will mark it. The same rule cuts both ways, though: a paper with exactly two authors never takes the abbreviation, so an et al. sitting next to a single name and an ampersand points to a mistake in the entry rather than in the source.

The numbers at a glance

When et al. takes over, by style — the range, and where each row actually shows up in coursework. Skim it first; the sections below explain why the range exists and which row applies to you.

The author-count thresholds, style by style

APA 7 and MLA 9 both draw their line at three authors, and they apply it in different places. In APA, a work with three or more authors becomes Erikson et al. in the first in-text citation you write, with no exception and no full first citation, and the reference list entry keeps the first author's surname followed by et al. In MLA 9, the same three-author rule applies inside the parenthetical and again in the works-cited entry, and MLA entries carry no year, so the in-text form is simply (Erikson et al.). The two styles therefore look similar in the body of a paper and differ on the page, which is exactly where a mixed reference list goes wrong: the APA entries keep a year after the closing parenthesis, the MLA entries do not, and a reader who spots one of each in the same list knows the list was assembled from two different sources.

Chicago is the one that punishes assumptions. In note form, Chicago names up to three authors and uses et al. from four; in the bibliography, it names up to ten and uses et al. only from eleven, with the first seven listed before the abbreviation. APA has its own upper rule that students rarely know: a reference list entry can carry up to twenty author names, and only at twenty-one do you list the first nineteen, insert an ellipsis and add the final author. Chicago's bibliography rule is stricter than its note rule, which is why a paper can carry a full author list in one place and et al. in the other without either being wrong. Read each rule as a number rather than a habit: count the authors first, then choose the form.

Punctuation and mechanics: the period, the comma and the italics

Three mechanical details decide whether an et al. entry reads as finished or as sloppy. First, the period: et al. ends in one, because the abbreviation stands for a full Latin phrase, and the period is never dropped in APA, MLA or Chicago. Second, the comma: in an author position there is no comma before et al., so the entry reads Sanchez, R., et al. and not Sanchez, R., and et al. Third, the case: the abbreviation is always lowercase, even when it opens a citation, and it is never written with a capital A. Some journals ask for et al without the period in a running head or a table, and those exceptions are local instructions rather than a style, so they do not travel into your reference list.

Italics are the detail that separates the three styles. APA and MLA keep the abbreviation in plain roman type, whatever sits around it, so a list of references set in APA with an italicized et al. looks like a formatting slip even when the punctuation is right. Chicago italicizes et al. when it stands in for authors in a bibliography entry and keeps it roman in the note form, which is why the same paper can carry the abbreviation in two different styles on facing pages. When you are unsure, check the style sheet rather than copying a classmate: a mismatched et al. is the kind of detail a formatting-conscious grader notices, because it usually means the rest of the entry was copied too, straight from a PDF with no reference list at all.

The mistakes that cost the most points

The first mistake is using et al. for two authors. Two names are short enough to print, so the abbreviation signals that the writer was too lazy to type two surnames, and instructors read it that way. The second is the stray comma before the abbreviation, the third is a capital A, and the fourth is italicizing the abbreviation in an APA or MLA paper. The fifth is the one that costs the most, because it changes the meaning: applying one style's threshold inside another style's paper, listing three authors in full inside a Chicago note that expects et al. at four, or abbreviating an APA reference list entry for a work with four authors when the full list was available. Each of these is cheap to fix and expensive to leave, because the reference list is the last part a grader reads and the first part they check.

Two more habits prevent most of the trouble. Write the reference entry from the source's own metadata rather than from memory, since the author count decides the form and memory is unreliable about counts. And check the entry against a tool that formats the whole list, because a correctly formatted list fixes the punctuation you would otherwise carry from the PDF you copied the citation out of. The same habit pays off in the body of the paper, where a wrong threshold produces an in-text citation that does not match the reference list behind it. If your style requires the full list and you have the PDF, the full list is always available, so the abbreviation is a convenience rather than a necessity. A reader who wants the full author list can still find it, and a reader who wants the paper can find it faster than a list of twenty-four names would have allowed.

Three minutes to a clean citation

Edge-case citations punish hesitation, not ignorance: the student who spends twenty minutes googling a no-author format loses more time to doubt than the format ever costs. Decide the pattern once — title moves forward, organization counts as author, n.d. when no date exists anywhere — and apply it mechanically. Consistency across your list matters more to graders than perfect recall of manual arcana.

Automate what's mechanical. The citation generator below formats journal articles, books, chapters and websites in all three major styles, including the awkward cases on this page. Paste the metadata, copy the output, done — the minutes you save belong to analysis, which is where rubric points actually live. Cross-check in-text forms against the table above and the reference list is submission-ready.