Direct comparison
Chicago Style vs APA: Differences Side by Side
Chicago style vs APA compared row by row: in-text form, reference lists, names, years, title case and et al. rules, APA 7th vs Chicago 18th.
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How do APA (7th ed.), Chicago (18th ed.) compare side by side?
The table below compares APA (7th ed.), Chicago (18th ed.) across 13 procurement-relevant dimensions, from systems offered through source.
Side-by-side comparison
| Dimension | APA (7th ed.) | Chicago (18th ed.) |
|---|---|---|
| Systems offered | One author-date system. | Two systems: notes-bibliography and author-date. |
| Typical fields | Psychology, behavioral and social sciences. | Notes-bibliography is typical of the humanities; author-date is more common in the sciences and social sciences. |
| In-text citation | Parenthetical (Author, year) with a comma; narrative Author (year). Direct quote adds the page: (Author, year, p. 20). | Author-date: (Author year, page) with no comma between name and year, for example (Jones 2021, 62). Notes-bibliography: numbered footnote or endnote. |
| Name of the end list | References. | Bibliography (notes-bibliography) or References (author-date). |
| Author names in the list | Surname and initials: Smith, J. | Surname and full first name: Smith, Jane. |
| Year in a list entry | In parentheses after the author: (2023). | Author-date: bare year after the author, followed by a period: Smith, Jane. 2023. |
| Article and book title capitalization | Sentence case for article and book titles. | Title case (Chicago 18 uses the terms title case and sentence case, 8.159-8.160). |
| Authors named in the end list | Up to 20 authors listed. | Up to six listed; with seven or more, the first three plus et al. (13.23, 13.107). |
| Et al. in text | Three or more authors: first author plus et al. from the first citation. | More than two authors: first author plus et al. (13.23, 13.107). |
| Block quotations | Start at 40 words; indented 0.5 in., no quotation marks. | Per two library guides: five or more lines or over 100 words; set off without quotation marks. |
| Publisher location and DOIs | No publisher location; DOI written as a https://doi.org/ URL. | No place of publication for books (14.30); DOI written as a https://doi.org/ URL. |
| When to pick each | Use APA when the instructor, journal or field specifies it (typically the behavioral and social sciences). | Use Chicago when specified: notes-bibliography for humanities work, author-date for an APA-like parenthetical system in Chicago form. |
| Source | Sources: APA Style instructional PDFs (apastyle.apa.org; reference guide, in-text citation checklist, guide to what is new in the 7th edition), Chicago Manual of Style 18th ed. what's-new page (chicagomanualofstyle.org), Skidmore Libraries and Memorial University Libraries Chicago guides, UVU Writing Center author-date handout; checked 2026-11. | Sources: APA Style instructional PDFs (apastyle.apa.org; reference guide, in-text citation checklist, guide to what is new in the 7th edition), Chicago Manual of Style 18th ed. what's-new page (chicagomanualofstyle.org), Skidmore Libraries and Memorial University Libraries Chicago guides, UVU Writing Center author-date handout; checked 2026-11. |
Common questions
Common questions about APA (7th ed.) vs Chicago (18th ed.)
What is the difference between APA and Chicago style?
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APA is one author-date system. Chicago is two systems: notes-bibliography (footnotes or endnotes plus a Bibliography) and author-date (parenthetical citations plus a References list). The closest match to APA is Chicago author-date, and the visible differences are the comma in the in-text citation, initials versus full first names, the placement of the year, and title capitalization.
Chicago style citation vs APA: which in-text form is which?
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APA parenthetical citations put a comma between author and year, (Smith, 2023, p. 47). Chicago author-date omits the comma, (Smith 2023, 47). Chicago notes-bibliography has no parenthetical author-date at all and uses a numbered note instead.
Is Chicago author-date the same as APA?
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No. Library guides describe it as similar to APA, but entries differ: APA uses initials, a parenthesized year and sentence-case titles; Chicago author-date uses full first names, a bare year and title-case titles.
Which should I use, APA or Chicago?
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Use whichever your instructor, journal or publisher specifies. If none does, follow the field convention: APA in the behavioral and social sciences, Chicago notes-bibliography in the humanities.
