Chicago vs APA format: when to use each one
Reviewed: August 19, 2026. Sources, review and corrections methodology
DIRECT ANSWER
Differences between Chicago and APA 7 format. Which one your university requires and how to apply each one correctly.
APA and Chicago are two widely used citation systems. Both attribute sources, but organize citations and references differently. The required style depends on the current instructions for your program, journal or course; confirm that source before formatting the document.
Where each format comes from
APA (American Psychological Association)
The APA style was first established in 1929 by a group of psychologists and anthropologists who needed a standardized way to present scientific articles. It has since evolved through seven editions, with the current 7th edition published in 2019. Its core focus is clarity, precision, and proper attribution of ideas in scientific and social science disciplines.
APA places heavy emphasis on the publication date because in fields like psychology, education, and social sciences, how recent the information is matters enormously. A 2010 study may be outdated compared to a 2024 one.
Chicago (The Chicago Manual of Style)
The Chicago Manual of Style was first published in 1906 by the University of Chicago Press. It is one of the oldest and most comprehensive style guides in the English-speaking academic world. Unlike APA, Chicago offers two distinct citation systems, which makes it more versatile but also more confusing for first-time users.
Chicago prioritizes thorough documentation of sources, particularly primary sources, historical archives, and legal documents — contexts where the exact provenance of material matters more than its publication date.
The two systems within Chicago
This is a point many students overlook: Chicago is not one format but two.
1. Notes-Bibliography
This is the most common system in humanities, history, and law. It uses footnotes (or endnotes) for citations and a bibliography at the end of the document.
How it works:
- The first time you cite a source, the footnote includes the full reference
- Subsequent citations of the same source use a shortened form
- The bibliography at the end lists all sources in alphabetical order
Example footnote (first citation):
- Roberto Martinez, Economic History of Honduras (Tegucigalpa: University Press, 2022), 145.
Example footnote (subsequent citations):
- Martinez, Economic History, 160.
Bibliography entry:
Martinez, Roberto. Economic History of Honduras. Tegucigalpa: University Press, 2022.
2. Author-Date
This works similarly to APA: parenthetical citations in the text with author and year. It is more common in natural sciences and social sciences when an institution requires Chicago rather than APA.
Example in-text citation:
(Martinez 2022, 145)
Important note: Unlike APA, Chicago Author-Date does not use a comma between the author and the year.
APA 7 in detail
In-text citations
APA exclusively uses the author-date parenthetical system. There are several variations:
One author:
- Parenthetical: (Martinez, 2023)
- Narrative: Martinez (2023) notes that...
Two authors:
- Parenthetical: (Martinez & Lopez, 2023)
- Narrative: Martinez and Lopez (2023) found that...
Three or more authors:
- From the first citation onward: (Martinez et al., 2023)
Organization as author:
- First citation: (World Health Organization [WHO], 2023)
- Subsequent citations: (WHO, 2023)
Direct quote (under 40 words):
- Martinez (2023) states that "the Honduran economy showed signs of recovery" (p. 45).
Direct quote (40 words or more):
- Presented as a freestanding block, indented 1.27 cm (0.5 in), without quotation marks
Reference list
In APA, the final section is titled "References" (not "Bibliography"). It only includes sources that were actually cited in the text. Each entry uses a hanging indent: the first line is flush left, and subsequent lines are indented 1.27 cm (0.5 in).
Book: Martinez, R. (2023). Research methodology. University Press.
Journal article: Lopez, A., & Hernandez, J. (2022). Climate change impact in Honduras. Central American Science Review, 15(2), 34-52. https://doi.org/10.xxxx
Website: Universidad Nacional Autonoma de Honduras. (2024). Thesis formatting guide. https://www.unah.edu.hn/formatting-guide
Detailed side-by-side comparison
| Aspect | APA 7 | Chicago (Notes-Bib) | Chicago (Author-Date) |
|---|---|---|---|
| In-text citation | (Author, year) | Numbered footnote | (Author year, page) |
| Final list | References | Bibliography | References |
| Includes uncited sources | No | Yes (can include consulted works) | No |
| Indentation | Hanging indent | Standard indent | Hanging indent |
| DOI | Required when available | Optional but recommended | Optional but recommended |
| Use of "et al." | From the 1st citation with 3+ authors | From the 2nd citation with 4+ authors | From the 2nd citation with 4+ authors |
| Ibid. | Not used | Permitted | Not used |
| Page number in citation | Only for direct quotes | Always recommended | Always recommended |
| Recommended font | Times New Roman 12pt or Calibri 11pt | No specific requirement | No specific requirement |
| Spacing | Double-spaced throughout | Varies by publisher | Varies by publisher |
Which format does each Honduran university require
Knowing which format to use is not a matter of preference — it is a matter of institutional regulations. Here is a general guide based on what we consistently see in the papers we review:
| University | Primary format | Notes |
|---|---|---|
| UNAH | Confirm with the faculty | Requirements may vary by faculty, degree and current guide. |
| UTH | Confirm with the program | Request the official guide or template that applies to your cohort. |
| UNITEC | Confirm with the program | Requirements may differ by degree, course and current guide. |
| CEUTEC | Confirm with the program | CEUTEC is part of UNITEC, but the applicable document still needs verification. |
| UPNFM | Confirm with the program | Verify the required style and any current institutional adaptation. |
| UNICAH | Confirm with the program | Request the current guide and distinguish citation style from institutional structure. |
| USAP | Confirm with the program | Do not generalize one degree's instructions to another. |
Key takeaway: a faculty may add its own cover, margin or structural requirements to a citation style. Verify the current institutional guide before applying modifications.
Bibliography vs References: the distinction that matters
This difference trips up many students:
References (APA):
- Only includes sources directly cited in the text
- If you did not cite it, it does not belong in the list
- There should be a one-to-one correspondence between in-text citations and reference entries
Bibliography (Chicago Notes-Bib):
- Can include sources consulted but not cited
- More flexible and comprehensive
- Allows you to demonstrate the breadth of your research
Practical rule: If your advisor asks for a "bibliography," they likely expect Chicago format or an institutional variation. If they ask for "references," they expect APA.
Footnotes vs in-text citations: pros and cons
Footnotes (Chicago)
Advantages:
- Do not interrupt the flow of the main text
- Allow for additional commentary and explanations
- Ideal for historical and legal discussions with many primary sources
Disadvantages:
- Can accumulate and make the document visually heavy
- Take up more space on each page
- Easier to make numbering errors
In-text citations (APA)
Advantages:
- The reader immediately identifies the author and date
- More compact and visually clean format
- Easier to verify citation-reference correspondence
Disadvantages:
- Can interrupt reading flow when there are many consecutive citations
- Do not allow explanatory notes within the citation itself (require separate notes)
Common mistakes with each format
Frequent APA 7 errors
-
Misusing "et al." — In APA 7, "et al." is used from the very first citation when there are 3 or more authors. Many students still follow the APA 6 rule, which required listing up to 5 authors the first time.
-
Omitting the DOI — If a source has a DOI, it is mandatory to include it. Leaving it out is a formatting error.
-
Using "Retrieved from" before URLs — APA 7 no longer requires "Retrieved from" for most online sources. It is only used when the content may change over time (such as social media pages).
-
Incorrect hanging indent — The reference list must use a hanging indent. Many students use a standard indent instead.
-
Including "p." or "pp." in paraphrased citations — Page numbers are only required for direct quotes, though they are recommended for paraphrased content.
Frequent Chicago errors
-
Confusing the two systems — Using footnotes in a document that should use author-date, or vice versa.
-
Not shortening subsequent citations — After the first full footnote, subsequent footnotes for the same source should use an abbreviated form.
-
Misusing "Ibid." — Some advisors do not accept "Ibid." Always check with your university.
-
Incorrect bibliography formatting — In the bibliography, the last name comes first (inverted order), but in footnotes the name appears in natural order (first name last name).
-
Missing page numbers — Chicago expects page numbers in nearly all citations, not just direct quotes.
The worst mistake of all
Mixing formats — APA in some citations and Chicago in others. It commonly happens when copying references from different sources. Google Scholar may export APA, Chicago or MLA depending on the selected style. If you do not verify each one, you end up with an inconsistent document that needs correction before submission.
How to avoid it:
- Define the format at the very beginning of your project
- Use a reference manager (Mendeley, Zotero) configured to the correct format
- Review all references at the end, one by one
- If you copy a reference from another source, reformat it manually
Tools for managing each format
| Tool | APA 7 | Chicago | Free | Notes |
|---|---|---|---|---|
| Zotero | Yes | Yes | Yes | Excellent for both formats. Browser extension available. |
| Mendeley | Yes | Yes | Yes | Good Word integration. Owned by Elsevier. |
| Google Scholar | Yes | Yes | Yes | Exports citations, but not always in perfect format. |
| Purdue OWL | Yes | Yes | Yes | Quick online reference for formatting rules. |
| Cite This For Me | Yes | Yes | Partial | Generates quick citations but can contain errors. |
Warning: No automated tool is 100% reliable. Reference managers make mistakes with Spanish-language sources, accented characters, and modified institutional formats. Always review your references manually.
Which format should you master
If you are a university student in Honduras, the short answer is: APA 7 first, Chicago second.
- APA 7 will be required for the vast majority of your assignments, regardless of your major
- Chicago will be needed if you study law, history, or a humanities-related field
- Vancouver is common in health sciences, but the program or journal must confirm it
Regardless of the format, what matters most is consistency. A document that uses a single format, even with minor errors, will always be better received than one that mixes two or three styles.
We review APA 7, Chicago and Vancouver against the source supplied by your program. The service identifies inconsistencies and documents the applied criteria without assuming one format for every university. Request a review quote.
Formatting may seem like a minor detail, but it's the #1 cause of rejections. Don't risk months of work over poorly formatted citations. Our specialists review every reference, every citation, and every formatting detail to make sure your document passes without corrections.
Primary and academic sources
These sources support the editorial review of this guide. Always verify the current rules of your own program.
- APA Style: Style and Grammar Guidelines — American Psychological Association
- Purdue Online Writing Lab — Purdue University
- Metadata Search and DOI Resources — Crossref
Need help with your project?
Our team can handle your thesis, research or technology project.
