When Do You Capitalize After a Colon?

If you ask two writers this question, you probably wouldn’t receive the same response. There isn’t a straightforward answer when it comes to figuring out when to capitalize after a colon.

While often used like an em dash or a semi-colon, the colon has multiple uses to both keep our sentences and numbers in line. But when do we capitalize the word that follows it?

Fortunately, there are tricks to remembering when to capitalize after a colon.

What is a Colon?

A colon is a punctuation mark that looks like two equally sized dots centered on the same (but invisible) vertical line. It looks like this ➡️ : 

You’ve seen colons used to denote time (9:35 AM), biblical quotes (Genesis 1:31), correspondence (To Whom It May Concern:) and a ratio between two numbers (2:3).

Colons are also used in three grammatical instances: introducing a list, between independent clauses and emphasis.

Introducing a List

The colon comes before a list of items in a sentence.

Example: The creamery specializes in three flavors: chocolate chip, peppermint and butterscotch.

If applying a colon before a list of items affects the flow of the sentence, then omit it from the sentence.

Correct: The creamery specializes in chocolate chip, peppermint and butterscotch.

Incorrect: The creamery specializes in: chocolate chip, peppermint and butterscotch.

Between Independent Clauses

A colon can be used between two separate independent clauses as long as the second clause explains or illustrates the first.

Example: I don’t have much time to learn French: I leave for France in four weeks.

Emphasis

A colon can be used to emphasize a single word or phrase at the end of the sentence, in the same way that an em dash can be used.

Example: After four days of deliberating, the jury reached a verdict: guilty.

---

When Do You Capitalize After a Colon?

More often than not, you do not capitalize after a colon. However, there are two instances where a capitalized word should follow a colon.

When a colon precedes a complete sentence, capitalize the first word after the colon.

Example: It’s rained for two straight days: The local roads are sure to be flooded.

There are some exceptions to this rule. In British English, you do not capitalize the first word after a colon when it precedes a complete sentence.

Some style guides, such as the Chicago Manual of Style, recommend capitalizing the word following a colon only if there are two explanatory sentences following the colon. If there is only one explanatory sentence following a colon, then you do not capitalize the first word after the colon to adhere to the Chicago Manual of Style.

One Sentence: Vincent doesn’t like to be called Vince: it reminds him of being bullied in middle school.

Two Sentences: Vincent doesn’t like to be called Vince: It reminds him of being bullied in middle school. He also thinks Vincent sounds more mature.

When a colon precedes a proper noun or acronym, capitalize that word after a colon as you would capitalize it in any other instance.

Example: I invited my friends to join me at the movies: Jane, Richard, Teresa and Zach.

---

When Do You Not Capitalize After a Colon?

Most uses of a colon do not require the word after the colon to be capitalized. When in doubt, don’t capitalize after a colon.

When a colon precedes a list, do not capitalize the first word after the colon (unless, of course, it’s a proper noun).

Example: I have three favorite colors: purple, green and blue.

When a colon is used for emphasis or precedes an incomplete sentence, do not capitalize the first word after the colon (unless, of course, it’s a proper noun).

Example: I only have one enemy: time.

How do you remember when to capitalize after a colon? Share your tricks in the comments section below.