Navigating the rules of capitalization in titles can be challenging, particularly with small words like “on.” So, is “on” capitalized in a title? The general rule is that you should keep “on” in lowercase unless it is the first or last word. But are there any exceptions to this rule?
Related:
Title Capitalization Rules per Style Guide
Depending on the context, the word “on,” aside from being a preposition, can also be an adverb and even an adjective. Do you have to capitalize it if it’s part of your paper’s title? We’ll break down how Chicago, AMA, AP, MLA, The New York Times, APA, Wikipedia, and Bluebook approach the capitalization of “on” in titles.
Chicago Manual of Style (CMOS)
In Chicago Style, it keeps prepositions like “on” in lowercase unless they appear as the first or last word. The exception to this is when “on” is an adverb. In such cases, “on” is capitalized as it functions differently within the title. For example, in the phrase “Carry On,” “on” is an adverb and is capitalized.
American Medical Association (AMA)
The AMA Style follows a rule similar to that of CMOS. Prepositions like “on” aren’t capitalized in titles unless they’re the first word of a title or the first word of a subtitle. For instance, “On Cardiovascular Health: A 2024 Study” is correct.
Associated Press Style (AP Style)
The Associated Press Stylebook also doesn’t capitalize “on” in titles unless it’s the first or last word. This style guide also doesn’t capitalize conjunctions, articles, or short prepositions unless for the same reason. “A Study on Childhood Development” is the correct title capitalization.
Modern Language Association (MLA)
Similarly, the MLA Handbook says short prepositions are lowercase except when they’re the first or last word or come after a colon. For example, “Current Perspectives on Modern Architecture” is correct, whereas “Current Perspectives On Modern Architecture” is not.
The New York Times Manual of Style and Usage
The New York Times doesn’t capitalize “on”; however, there is an exception to this rule: You should capitalize “on” if it (and other short prepositions) functions as an adverb.
American Psychological Association (APA)
APA style maintains that nouns, pronouns, verbs, adjectives, and adverbs are capitalized. On the other hand, you should keep conjunctions, articles, and prepositions under four letters in lowercase unless they appear as the first or last word of a title.
Wikipedia Manual of Style
The Wikipedia Manual of Style also generally follows the rule that prepositions like “on” aren’t capitalized in titles unless it is the first or last word in a title. However, there are two exceptions to this rule: if it’s part of a phrasal verb and if it’s the first word of a compound preposition.
Bluebook
The Bluebook, which governs legal writing, also doesn’t capitalize “on” in titles. This aligns with the standard practice of leaving prepositions lowercase unless they’re the first or last word. For example, “On Crime and Punishment: A Modern Analysis” is correct.
When Should You Capitalize On
Again, “on” is not capitalized. However, there are some instances in which you should capitalize it.
- First Word: All major styles agree that “on” is capitalized when it’s the first word in a title. The title “On the Origin of Species” follows this capitalization rule.
- Last Word: Most style guides agree that when “on” is the last word, it’s capitalized. For example, “Key Insights to Reflect On” follows this rule.
- Used as an Adverb: When “on” is an adverb, capitalize it. Take “On the Importance of Grammar,” for example. In this case, “on” indicates progress or growth, so it’s capped.
- Part of a phrasal verb and the first word of a compound preposition: This rule is only applicable to the Wikipedia Manual of Style.
Tip: The first letter of the first word is always capitalized.
When Shouldn’t You Capitalize On
In general, you shouldn’t capitalize “on” if it functions as a preposition in a title. For instance, it is the second word of a title, then keep it in lowercase. This title capitalization rule applies to different style guides (CMOS, AMA, AP, MLA, The New York Times, APA, Wikipedia, and Bluebook).
Final Thoughts
So, “is on capitalized in a title?” Generally, when “on” is used as a preposition, it should not be capitalized —unless it is the first or last word in the title.
Want to simplify title capitalization? Use this free title capitalization tool that uses the latest sentence case and title case rules.
