APA Style uses two types of capitalization for titles of works (such as paper titles) and headings within works: title case and sentence case.

In title case, major words are capitalized, and most minor words are lowercase. In sentence case, most major and minor words are lowercase (proper nouns are an exception in that they are always capitalized).

  • major words: Nouns, verbs (including linking verbs), adjectives, adverbs, pronouns, and all words of four letters or more are considered major words.
  • minor words: Short (i.e., three letters or fewer) conjunctions, short prepositions, and all articles are considered minor words.

Title case capitalization is covered in Section 6.17 of the APA Publication Manual, Seventh Edition

How to Implement Title Case

In title case, capitalize the following words in a title or heading:

  • the first word of the title or heading, even if it is a minor word such as “The” or “A”
  • the first word of a subtitle
  • the first word after a colon, em dash, or end punctuation in a heading
  • major words, including the second part of hyphenated major words (e.g., “Self-Report,” not “Self-report”)
  • words of four letters or more (e.g., “With,” “Between,” “From”)

Lowercase only minor words that are three letters or fewer in a title or heading (except the first word in a title or subtitle or the first word after a colon, em dash, or end punctuation in a heading):

  • short conjunctions (e.g., “and,” “as,” “but,” “for,” “if,” “nor,” “or,” “so,” “yet”)
  • articles (“a,” “an,” “the”)
  • short prepositions (e.g., “as,” “at,” “by,” “for,” “in,” “of,” “off,” “on,” “per,” “to,” “up,” “via”)

When to Use Title Case

Use title case for the following:

  • titles of articles, books, reports, and other works appearing in text

In the book Train Your Mind for Peak Performance: A Science-Based Approach for Achieving Your Goals

In the article “Turning Frowns (and Smiles) Upside Down: A Multilevel Examination of Surface Acting Positive and Negative Emotions on Well-Being”

  • titles of tests or measures, including subscales

Beck Depression Inventory–II 

  • all headings within a work (Levels 1–5; these are also bold or bold italic)
  • the title of your own paper and of named sections and subsections within it

the Results section

Journal of Latinx Psychology

Chicago Tribune