Colons: When to Use Colons in Writing (Examples)

Would you like to know what colons are and how to use them? If so, you've come to the right place. This article will teach you everything you need to know to use them properly.

In short:

• A colon is a punctuation mark used to introduce lists and ideas, provide further clarification, or place emphasis.

This guide is part of our free online Grammar Book.

What Are Colons?

So, first of all, what is a colon?

• It's a punctuation mark that joins two related clauses.

The clause that precedes the colon should always be independent, and then the information that follows the colon should be an extension of the information in that independent clause. Sometimes the second clause is independent, and sometimes, it's dependent.

In other words, a colon replaces words like:

• such as
• and those are
• as follows
• it's because

Look at the following examples, and try replacing the colons with these phrases.

I have many different kinds of flowers growing in my garden: roses, tulips and lavender, to name a few. 

She knows why I'm avoiding her: I don't want to talk about what happened at lunch the other day.

Allow me to introduce the topic of today's workshop: basket weaving using traditional basketry techniques.

See? It works! If you're a visual or imaginative learner, you can also think of a colon as an arrow pointing toward the clause that follows it.

So how is a colon different from a semicolon?

• The truth is that they're actually quite similar, except that while a colon replaces words like the ones presented above, a semicolon replaces conjunctions.
• Plus, semicolons can separate items in a list, whereas colons can only introduce them.

When to Use Colons

Now that you've got an idea of what a colon is, let's look into the different situations you can use it in. I will explain those in this section, and you'll notice that there's the grammatical use of colons - which is basically to introduce - and then there's the use of colons outside of grammar contexts.

Read on to find out more.

To Introduce Lists

Colons are often used when writing lists because they allow you to introduce them. It works whether your list is made of single words, phrases, or full-on complete sentences.

Here's an example of each:

“Three things of life that once gone, never come back : time, words & opportunity.” — Unknown

“They say a person needs just three things to be truly happy in this world: someone to love, something to do, and something to hope for.” — Tom Bodett

"In three words I can sum up everything I've learned in life: It goes on." — Robert Frost

To Give Further Clarification

Semicolons are great for giving further clarification or even placing emphasis on something. That is, the clause after the colon elaborates further on the idea introduced in the preceding clause.

For example:

There's only one woman in my life: my mother.

After all that I felt only one thing: regret.

I desire one thing and one thing only: to go to the beach.

As you can see, the part that precedes the semicolon is a complete sentence and technically doesn't need the part that comes after the colon. That's why it's only there to provide further clarification.

To Introduce Quotations

You can use a colon to introduce a quotation if it's a complete sentence or when the introduction is an independent clause.

For example:

It's like Einstein once said:

“If you can't explain it to a six year old, you don't understand it yourself.”

You might see commas being used to introduce direct quotes, and that's correct if the introduction is not an independent clause.

For example:

He said, "My dog has gone missing."

To Separate Units of Time

This is the first of the colon's non-grammatical uses:

• To separate units of time and ratios.

Here are a couple of sentences that demonstrate this:

The show starts at 9:15 pm.

The ratio of girls to boys in my high school is 3:1.

To Separate Titles from Subtitles

You can use colons to separate titles from subtitles. This works with movies, books, academic journals; you name it.

Here are a few examples:

Jurassic World: Dominion

A Brief History of Time: From the Big Bang to Black Holes 

COVID-19 disruption on college students: Academic and socioemotional implications

To Name Speakers in a Dialogue

Colons are handy for reporting a dialogue in a theatre play or an interview, for instance. Just write the speaker's name followed by a colon, then write what they said.

Interviewer: How do you feel about the reception of your latest book?
Stephen King: I'm thrilled that so many people worldwide enjoy my stories.

Juliet: Ay me.
Romeo: She speaks.
Juliet: O Romeo, Romeo, wherefore art thou Romeo?

Common Colon Mistakes

Now we've covered the primary uses of a colon, let's look at the most common mistakes people make when using them.

Don't Use Colons Between a Verb/Preposition and Its Object

Number one is using a colon between a verb and its object or complement and between a preposition and its object.

• This doesn't work because it goes against the rule that the sentence before the colon should be complete (independent clause).

Take a look at the following sentence:

When I get home I want to: get into my pajamas and watch TV. ❌

This is an example of a colon being used between a preposition ('to') and its object ('get into'). 'When I get home, I want to' is not a complete sentence (it can't stand alone).

Here's another example, this time of a colon between a verb and its object:

This year I want: to go on vacation, learn to surf, and learn Spanish. ❌

Again, it doesn't work because 'this year I want to' is not a complete sentence.

• You should also never use a colon in a sentence that uses the kinds of words it replaces, like "such as" and "those are."
• Either use the words or use the colon, not both.

As an example, a sentence like the following is incorrect.

We should get various drinks for our picnic, such as: lemonade, iced tea and soda. ❌

Know When to Use Capitals

Should you use capitals after a colon? It depends.

You should use a capital if:

• the first word after the colon is a proper noun
• the part that comes after the colon is a complete sentence (independent clause)

Here are some examples to illustrate these rules:

They've opened a new ride at Disneyland: Guardians of the Galaxy.

I'm not surprised the food at the wedding was amazing: They hired a world-renowned chef.

Concluding Thoughts on Colons

Well, that concludes this article on colons and how to use them. I hope you found it helpful.

Let's summarize what we've learned:

• Colons are punctuation marks.
• Use colons to introduce an idea or quotation, place emphasis, or elaborate.
• You can also use colons to write the time or ratios, separate a title from its subtitle, or name a speaker. 
• Only independent clauses can precede a colon.
• Capitalize the first word after the colon if it's a proper noun or a complete sentence. 

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