How to Use a Colon in a Sentence

What Is a Colon?

A colon, technically speaking, is a punctuation mark consisting of two equally sized dots in a vertical configuration (see the image above). It is used to mark a major division in a sentence, to indicate that what follows is an elaboration, summation, implication, etc., of what precedes it. Think of the colon as a gate, inviting one to go on. Want to know more? Read further:

1. Use the colon to punctuate the end of a sentence when a list of items follows, as follows:

The class will expose you to the following topics: politics, history, and economics.
This first-aid kit includes these items: a flashlight, an extra set of batteries, a space blanket, gauze, tape, and aspirin.

You have 3 choices:
1. Buy the car.
2. Buy the ticket.
3. Save the money and take a nap.

2. Use a colon between two sentences when the the second sentence elaborates or explains the content of the first sentence.

She had it all: looks, intelligence, wit, and charm. She also had a piercing gaze, and it was aimed at one place, and one place only: my heart.

This I know: Do or do not. There is no try.

3. The colon is the punctuation to reach for when you're writing a business or formal letter.

Dear Mr. Jones: You know there's something happening, but you don't know what it is, do you?

4. Use a colon to separate an independent clause from a quotation that the clause introduces:

The director often used his favorite quotation from Shakespeare's The Tempest:
As you from crimes would pardon'd be,
Let your indulgence set me free.
When not to use the colon

1. Remember this: the clause that precedes the punctuation mark should be able to stand on its own as an independent clause. It should have a subject and a predicate.

2. Don't use the colon in the following situations:

When a clause includes an introductory word such as for example, or namely.

Her recipe for cake included flour, eggs, milk, and anchovies. It was not widely appreciated. (Don't use a colon after "included.")

His favorite cereals were hot buttered groat clusters, TastyWheat, and Frosted Chicken-Os. (No colon after "were.")

She was a big fan of old movies. For example, The Maltese Falcon, The Tramp, and Creature From the Black Lagoon. (No colon after "example.")

3. Remember this as well: Do not use a colon to introduce a list that is the complement of a verb or the object of a preposition.

Incorrect: The toys we took to the sleep over were: army men, hot wheels, and Barbie dolls.(The colon separates the verb from its complement).

Correct: We took these toys to the sleep over: army men, hot wheels, and Barbie dolls.
Incorrect: We have vacationed in: Philippines, China, Thailand, and Hong Kong. (Colon separates the preposition from its object).

Correct: We have taken a vacation in the following countries: Philippines, China, Thailand, and Hong Kong.

Remember, there is still need for an "and" before the last word you are listing, even when using a colon. For example, “There are so many things I need to purchase for the party: balloons, streamers, food, soda, gifts, and plates.”

When a colon follows quoted matter, the colon goes outside the quotation marks. For example, "There were three people to whom he sang "The Girl From Ipanema": his mother, his sister and his best friend."

If a colon is followed by a complete sentence, capitalize the first word after the colon. For example, "While in Venice, he did something he had never done before: He took a gondola ride." (Compare to this: "While in Venice, he did something he had never done before: took a gondola ride."