A Definitive Guide To Capitalization Rules

There are a few specific cases where words should be capitalized. They’re easy to remember. In English, capital letters are most commonly used at the start of a sentence, for the pronoun I, and for proper nouns.

Capitalize the first word in every sentence

You should always capitalize the first letter of the first word in a sentence, no matter what the word is. Take, for example, the following sentences: “The weather was beautiful. It was sunny all day.” Even though the and it aren’t proper nouns, they’re capitalized here because they’re the first words in their sentences.

Capitalize the pronoun I

Pronouns are words that replace nouns. I, you, and me are all examples of pronouns. While you and me are usually lowercase, the pronoun I should always be capitalized, regardless of where it appears in a sentence.

For example, in A Beautiful Mind, Sylvia Nasar writes, “What I got back was an envelope on which my address was written in different-colored crayons.” Here, the pronoun I is correctly capitalized even though it isn’t at the beginning of the sentence.

Capitalize proper nouns

A proper noun is the special noun or name used for a specific person, place, company, or other thing. Proper nouns should always be capitalized.

Names of people

People’s names are proper nouns, and therefore should be capitalized. The first letter of someone’s first, middle, and last name is always capitalized, as in John William Smith.

Names of places

Other proper nouns include countries, cities, and sometimes regions, such as Bulgaria, Paris, and the American South. Geographic features that have names should also be capitalized, as in Mt. Kilimanjaro and the Pacific Ocean.

Landmarks and monuments also start their proper names with capital letters, such as the Empire State Building and the Golden Gate Bridge. Street names are always capitalized, too (e.g. Main Street).

Names of companies and trademarks

The names of companies and organizations should also be capitalized, such as Nike and Stanford University. There are some exceptions: sometimes a company may choose not to use a capital letter at the beginning of its name or product as a stylistic choice. Examples include eBay and the iPhone.

Capitalize honorary and professional titles 

Titles like Mr., Mrs., and Dr., should be capitalized. When addressing someone with their professional title, you should use a capital letter at the beginning. For example, you’d address a letter to the president as “Dear President Obama.” Similarly, you should capitalize job titles when they come before a person’s name, as in “General Manager Sheila Davis will be at the meeting.” Also use a capital letter when you’re directly addressing a person by their title without using their name, as in “We need the paper, Senator.”

Capitalize familial relationships 

Words that indicate family relationships should also be capitalized when used as titles in front of a person’s name. However, if you’re just talking about relationships with no names involved, the titles shouldn’t be capitalized. For example, you’d capitalize “Uncle Ben and Grandpa Ed will be at the picnic,” but you wouldn’t capitalize them in a sentence like “My uncle and my grandpa will be at the picnic.” Similar to the rules for professional titles, you should capitalize the names of family titles when they’re used in place of proper names. For instance, in Jane Eyre Charlotte Brontë writes, “She is at the lodge, Aunt.”

Capitalize most words in a title

The titles of books, songs, newspapers, and works of art should all be capitalized. Examples include Moby Dick, “Jailhouse Rock,” New York Times, and The Last Supper.

Capitalize days, months, and (sometimes) seasons

The names of days and months should be capitalized, such as January, September, Wednesday, and Sunday.

A season should be capitalized when it’s being used as part of a proper noun as in Winter Olympics. In poetry and other literature, personification is giving an animal, inanimate object, or abstract notion the qualities and attributes of a human. When a season is used this way, it should be capitalized. (Take, for example, how Charles Mair uses summer in a poem: “We will muse on Summer’s ploys.”)

Capitalize holidays

The names of holidays, such as Christmas, Halloween, and Hanukkah, are capitalized because they are considered proper nouns. You would not, however, capitalize a season: Christmas season. But if you add day to a holiday, you would capitalize this word: New Year’s Day and Christmas Day.

Capitalize time periods

Historical eras should be capitalized. For instance, use Middle Ages, Dark Ages, and the Renaissance. You’d also capitalize prehistoric eras such as Stone Age and Bronze Age.

Capitalize countries, languages, and nationalities

The names of countries are proper nouns, which means they are capitalized, of course.  Languages and nationalities are capitalized as well. A person who is from Kenya, is a Kenyan and likely speaks Swahili. A Chilean is a person from Chile, where the official language is Spanish.

Capitalize acronyms

Acronyms should be capitalized. NASA (National Aeronautics and Space Administration), POTUS (President of the United States), and DOB (Date Of Birth) are all capitalized. Some acronyms have been incorporated as recognizable words that should not be capitalized (laser, or “light amplification by stimulated emission of radiation;” when in doubt, it’s best to consult a dictionary.

Of course, in informal conversations (like texting), acronyms (lol, brb, idk, etc.) aren’t always capitalized. Not all rules apply to very casual writing styles.

Capitalize after certain punctuation

Of course, you already know to capitalize at the start of each sentence. There are other interesting sentence structures that require capitalization.

After the first word in a quote

When a quote is added to a sentence, it is introduced with quotation marks and a capital letter: When my father asked where I was going, I said, “Some of my friends are going to the movies.”

When the attribution is in the middle of the sentence, capitalization is also important: “The library is closed,” he said, “but you can return your books in the drop box.” In this case, the first word (the) is capitalized. Because the sentence continues after the attribution, the word but is not capitalized.

Similarly, a colon may introduce a quote that comes after an independent clause. For example, “Bob seemed to like that idea‘Yeah, let’s do that!'” In this sentence, the words before the colon could stand alone as a complete sentence. The colon emphasizes the coming quote.

(Sometimes) after a colon and semicolon

If what follows the colon is a complete sentence, some style guides (such as the American Psychological Association’s) do recommend capitalizing the word that follows the colon.

  • It snowed all morning: The roads were impassable by 8 am.

Capitalization after a semicolon is not required and would be grammatically incorrect. When an explanation takes the form of a second independent clause that follows a main independent clause, you can join the two clauses into a single sentence with a colon. Here is an example: Jenny had an idea: she would pick up a cake on her way to her friend’s house.

Get that essay, email, or letter to Nana over the finish line with a little writing help from Grammar Coach™. Get grammar check, spelling help and more free!