Capitalization Rules | Ultimate Guide & Examples

English has many rules for capitalization. In general, the first word of a sentence, the pronoun “I,” and all proper nouns (e.g., “Lake Tahoe,” “Texas State University”) are capitalized.

Beyond that, there are more detailed rules that will be covered in the sections below and are summarized in the following table.

Words that are always capitalized

We’ll start with the easy guidelines. There are a few groups of words in English that are always capitalized.

The first word of a sentence

The first word of a sentence is always capitalized, even if it would not typically be capitalized on its own.

Proper nouns

Proper nouns name a specific person, place, thing, or organization (e.g., “Colin,” “Prospect Park”). They should always be capitalized, as should the adjectives that derive from them (e.g., “Freudian,” “Irish”).

Common nouns, on the other hand, indicate a general category or nonspecific item. They are not typically capitalized (unless they are used as the first word of a sentence or as part of a title).

The pronoun I

The subject pronoun “I” is always capitalized, including when it is used in contractions (e.g., “I’m,” “I’ve,” “I’d”).

Capitalization of titles

Most major style guides (including APA, MLA, and Chicago) use the following rules for capitalizing titles of works of art, such as books, movies, and articles, in the main body of a text:

• Capitalize the first and last words of the title
• Capitalize all nouns, pronouns, verbs, adjectives, adverbs, and subordinating conjunctions
• Use lowercase for articles and coordinating conjunctions and prepositions of three letters or fewer.

Prepositions of four letters or more (e.g., “with,” “through”) are treated in different ways. APA Style requires capitalizing them, while MLA treats them like all other prepositions and lowercases them.

Headings and subheadings

Headings in papers can be written in title case (following the same rules as titles of other works) or in sentence case (capitalizing only the first word and any proper nouns). You should consult your style guide on how to capitalize headings, and make sure you are consistent throughout your document.

Times and events

Specific ages and eras are considered proper nouns and are capitalized (e.g., “the Middle Ages”). Centuries, however, are considered common nouns and are lowercase (e.g., “the eighteenth century”).

Days of the week (e.g., “Monday”), months of the year (e.g., “July”), and holidays and festivals (e.g., “Thanksgiving”) are proper nouns and are thus capitalized. But the names of the four seasons are considered common nouns and are generally not capitalized (though many style guides recommend capitalizing “Spring Break”).

Directions and regions

Directions (“north,” “south,” “east,” and “west”) are not capitalized when they are used as directions. They are capitalized, though, when they are part of a proper name or used to name a specific region. It can be difficult to determine whether directional words are being used as part of a specific proper noun, so it’s best to consult a style guide or dictionary.

Capitalization within quotations

If the quoted material forms a complete sentence, capitalize the first word of the quote.

When you fully incorporate a quotation into your own sentence, you do not need to capitalize the first word. This is true even if the beginning of the quotation is the beginning of a sentence in the original source.

Capitalization after a colon

If what the colon introduces is not a complete sentence (i.e., a list or phrase), do not capitalize the first word (unless it is a proper noun).

If the colon introduces a full sentence, different style guides have different advice. APA Style advises capitalizing the first word of the sentence.

Chicago style, however, recommends not capitalizing the first letter unless there is more than one explanatory sentence.

Acronyms and initialisms

Both acronyms and initialisms are abbreviations using the first letters of a series of words. Acronyms are pronounced as their own word (e.g., “NASA,” “FOMO”), while initialisms are pronounced letter by letter (e.g., “FBI,” “NCAA”). Both should be capitalized, though occasionally acronyms become so common that they are used as a common noun and not capitalized (e.g., “scuba”).

A common mistake people make is capitalizing every word of an acronym when it is spelled out. This is not necessary unless the term itself is a proper noun.

Job titles

Job titles are capitalized when they precede a person’s name, which makes them part of a proper noun (e.g., “Prime Minister Trudeau,” “Professor Wu”).

When used on their own in a sentence, the title is lowercase (e.g., “The prime minister will visit Mexico next week”).

Job titles are typically also capitalized in email signatures, job listings, and résumés and CVs.

Frequently asked questions about capitalization

What words do not get capitalized?

There are no words that are never capitalized in English because any word that begins a sentence should be capitalized. Additionally, words that are part of titles (except for articles, coordinating conjunctions, and short prepositions) are generally capitalized.

When not used in titles or as the first word of a sentence, words other than proper nouns and the first-person pronoun “I” are generally lowercased in English.

A free QuillBot Grammar Check can help you make sure you’re capitalizing words correctly.

What word is always capitalized?

The first-person pronoun “I” is always capitalized in English. This includes its use in contractions (e.g., “I’m,” “I’ve,” “I’ll,” and “I’d”).

This rule is sometimes broken in poetry or in very casual text messages. But, in all other types of writing, “I” should always be capitalized.

Use QuillBot’s free Grammar Checker to catch any mistakes with capitalization.

What are APA capitalization rules?

APA capitalization rules depend on what part of a paper you are writing. In the body of the text, standard capitalization rules should be followed (e.g., capitalize proper nouns and lowercase common nouns).

For titles of works and headings, APA Style uses two types of capitalization:

• In title case, all words are capitalized except for articles and prepositions and conjunctions of three letters or fewers.
• In sentence case, only the first word and any proper nouns are capitalized.

Title case vs sentence case in APA Style

	Use	Examples
Title case	Titles of articles, books, and other works in the body of the text	Freud’s The Interpretation of Dreams was a seminal influence …
	The title of the paper itself	Depression and Anxiety in Students Experiencing Homelessness
	Headings and figure and table titles	Theoretical Background
	Titles of journals and other periodicals on the reference page	Journal of Personality and Social Psychology
Sentence case	Titles of articles, books, reports, and webpages on the reference page	Stellar, J. E., & Willer, R. (2018). Unethical and inept? The influence of moral information on perceptions of competence. […]
	Table column headings and entries, table and figure notes	Number of participants

Are academic concepts capitalized?

In general, academic concepts are not capitalized; most are common nouns. This includes disciplines, models, theories, and frameworks (e.g., “string theory,” “existentialism”).

Common nouns are not capitalized even when they are used alongside proper nouns or adjectives (which are always capitalized) in the name of an academic concept (e.g., “Newton’s laws,” “Juvenalian satire”).

QuillBot’s free Grammar Checker can help you make sure you’re using capitalization correctly.

Is mom capitalized?

Words that refer to family relationships (e.g., “mom,” “dad,” “grandma,” “uncle”) are not capitalized unless they are used in place of a name.

• My mom is the best.
• My Mom is the best.

• I love you, Mom.
• I love you, mom.

• Is Uncle Jay coming to the wedding?
• Is uncle Jay coming to the wedding?

• Is your uncle coming to the wedding?
• Is your Uncle coming to the wedding?

QuillBot’s free Grammar Checker will help you use capitalization correctly.