Is “To” Capitalized in a Title?
“To” is normally lowercase in the middle of titles under APA, Chicago, and MLA-style capitalization when it functions as a short preposition; Chicago also explicitly keeps “to” lowercase as an infinitive marker in ordinary mid-title position. Edge position can change the result.
Usually no in the middle of a title. “To” is a two-letter preposition in many titles, and Chicago also keeps the infinitive marker “to” lowercase internally. Capitalize it when it is the first or, where the chosen style requires it, the last word.
Key details
Further guidance
As A Preposition
As a short internal preposition, “to” remains lowercase under APA’s short-minor-word rule and Chicago 18’s four-or-fewer-letter preposition rule. MLA editorial guidance likewise lowercases internal prepositions.
As An Infinitive Marker
Chicago specifically says the infinitive marker “to” remains lowercase in ordinary mid-title position, as in “Born to Run.”
Edge Positions
Chicago capitalizes the first and last word regardless of syntax. MLA’s current ninth-edition public guidance also identifies first and last words as capitalized.
Practical Application
For an internal “to,” first identify the selected title style and its grammatical role. APA/MLA commonly lowercase a short prepositional “to,” and Chicago also lowercases the infinitive marker internally; edge-position rules can override the internal rule.
Practical Rule
A robust converter must distinguish position and style before changing the token. This guide does not use a global “always lowercase to” rule.
Reader Check
Is “to” internal or at an edge, and is it functioning as a preposition or infinitive marker under the style you are applying?
Worked Example
Example: Chicago keeps the infinitive marker lowercase in “How to Write Clearly,” while a first-word “To” is capitalized because it begins the title.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- Title case capitalization (opens in a new tab)American Psychological Association · APA title-case rules
- Headlines and Titles of Works — “to” in infinitives (opens in a new tab)The Chicago Manual of Style / University of Chicago Press · Chicago treatment of “to” in titles, including infinitives and edge positions
- What's New in the 18th Edition (opens in a new tab)The Chicago Manual of Style / University of Chicago Press · Chicago 18 title-case terminology and five-letter-preposition change
- How should I capitalize the title of a handout? (opens in a new tab)MLA Style Center / Modern Language Association · MLA title-style capitalization
- In MLA style, should any part of a two-word preposition be capitalized in a title? (opens in a new tab)MLA Style Center / Modern Language Association · MLA editorial guidance on internal prepositions in titles