Learn how and when to use a colon (:) with examples and useful colon punctuation rules. The mark (:) in the middle of a sentence indicates that the second half of the sentence explains or provides examples of what is described in the first half.
Colon (:)
What is a colon?
The punctuation mark (:) consists of two dots, one above the other. It signals that the second half of the sentence is going to explain or give examples of something mentioned in the first half.
Examples:
- I’m taking four classes this semester: biology, philosophy, physics, and ancient Greek.
- I’ll give him credit for one thing: he’s certainly persistent.
Learn more about the difference between a colon and a semicolon.
When to use a colon
Use the mark to introduce something in the second half of the sentence that explains, completes, or gives examples of what is mentioned in the first half.
It may introduce a list.
- The following novels will be on the exam: Moby Dick, Great Expectations, and The Brothers Karamazov.
- Here are some of my favorite foods: fried chicken, lobster, and corn on the cob.
The mark (:) may introduce an explanation or example.
- She’s ready to move on to a new school: this one has taught her everything that’s available there.
- Amsterdam is filled with great museums: just walk around and you’ll find one.
Unlike the semicolon, the colon may introduce a clause or just a series of nouns that do not form a complete sentence.
Examples:
- Complete sentence: Manchester United face a difficult task: they must win the next six matches.
- Clause: Bring me a 50-lb. box of cat litter: the kind that contains deodorant.
- List: We’re ready for the following patients: López, Santamaria, Trinidad, Rincónes.
The mark (:) may also be used to build up to something that is revealed after the colon.
- I can bring a great strength to your company: my writing skills.
- She said she wanted to be sure to go to one place before she died: New Zealand.
How to use the colon with quotation marks
The mark (:) always goes outside the closing quotation mark, whether you are writing British or American English.
- “Always look before you leap”: that is useful advice.
Special usage
If both halves of the sentence are complete sentences in themselves, either a colon or a semicolon may often be used. The mark (:) places greater emphasis on what comes after the colon.
- We can enter at the next gate; there are fewer people there.
- We have a problem: hundreds of people are outside, but we have nothing to sell to them.
Common Colon Mistakes and How to Avoid Them
Common Grammar Mistakes When Using a Colon
A colon is most often used to show that a quote, important explanation, or list is about to follow. What’s important is knowing where to place it in the sentence. Many people do so incorrectly because they do not set up the first part of the sentence to show that what comes after the colon is important to the overall sentence. Here are some common examples and how to correct them:
Incorrect I love my girlfriend for: her smile and her laughter.
The colon here is unnecessary because you aren’t properly setting the first part of the sentence up to show that you are offering a simple explanation. You always want to be as clear as possible when using a colon, because you are trying to show emphasis on the next part of the sentence. Here, an explanation is being offered why the individual loves their girlfriend, but it isn’t being set up in the first part of the sentence to create emphasis. Here is how it should read:
Correct I love my girlfriend for two reasons: her smile and her laughter.
Now you have created the emphasis to highlight how important the explanation is.
Incorrect Sam likes: reading, writing, and playing video games.
Here, you are offering a list as the next part of the sentence following the colon. The problem here is, you haven’t set up the list correctly for a colon to be necessary. You should only ever use a colon when it’s clear that the following part of the sentence is a logical explanation, an obvious list, or a clear quote. So, you’d have to set up this sentence like this:
Correct Sam liked three things: reading, writing, and video games.
Now you’ve created the buildup to the list, so it is acceptable to use a colon.
Should You Capitalize the First Letter after a Colon?
Many people make this mistake because there is some confusion surrounding it. In American English, only capitalize on the next word if it is an independent clause that can stand as a complete sentence on its own (although this is left up to writers’ choice, it isn’t necessarily a rule). If it is a dependent clause that makes little sense on its own, then you shouldn’t capitalize on the next word (that is a rule). You should also never capitalize if you are introducing a list. Look at these examples below:
Incorrect The weather reporter said the weather was: “Hot, sunny and dry.”
Introducing the quote in this way would be technically incorrect, because ‘hot, sunny and dry’ is a dependent clause that makes little sense on its own without the first part of the sentence. So, it should read like this:
Correct The weather reporter said the weather was: “hot, sunny and dry.”
This would be correct because it shouldn’t be capitalized. If it was an independent clause that followed the colon, then a capital letter would make sense.
Colon vs. Semicolon vs. Dashes
We already know when a colon should be used, but when should a semicolon or dash be?
Semicolon
You use a semicolon when you are connecting two independent clauses that link because of similar ideas, or when introducing a list that is more complicated because it has explanations. Here are two examples of how semicolons are most commonly used:
- I like to go to the library; there are always so many excellent books there.
- You should bring a toothpaste for hygiene; a bottle of water for hydration; a waterproof coat in case it rains; and a snack to eat whilst en route.
Dashes
You can use dashes (more commonly known as em dashes in this style of writing) in the place of parentheses so it doesn’t make for an odd end to a sentence, or you can use them to replace a colon in more casual writing. Like this:
- He knew there was only one thing for it, so he ran – or rather, scurried. – We could have written this sentence as He knew there was only one thing for it, so he ran (or rather, scurried). But the dash looks better, even though both are correct.
- Sam liked three things – reading, writing, and video games. – Notice how this replaces the colon in the example from earlier.
Examples of Using Colons in Sentences:
Lists
- Pick up three things from the store: oranges, apples, and pears.
- Please bring these fundamental things: a toothbrush, a coat, and a pair of boots.
Quotes
- The dentist said I had to: “brush twice daily and floss as often as possible.“
- The man had to repeat himself three times: “You’re going the wrong way.“
Independent Clauses/Explanations
- Life can be complicated: Sometimes it’s good and sometimes it’s bad.
- Spending time with friends can be fun: You’ll laugh until you cry when you’re together.
Example Sentences
- Samuel plays four sports: volleyball, soccer, badminton, and tennis.
- I need the following items from the store: butter, sugar, and flour.
- PS: Don’t forget to bring your towel.
- Please bring the following fruits: apples, plums, oranges, and bananas.
- Q: When do you want to leave the country? – A: As soon as possible.
- You have two choices: finish the work today or lose the contract.
- Detective Holt said: “The kidnapper is a man we must catch and the sooner the better.”
Colon Quiz
See if you can decide if the following sentences have used a colon correctly or incorrectly.
Questions
1) I want to visit Florida for: the sun and the atmosphere.
2) There are two major reasons I’m here today: to help, and to support.
3) Please bring: clothes, shoes, bags, and makeup.
4) You’ll need: orange juice, lemonade, and ice.
5) Life’s like a puzzle: Sometimes you get it, sometimes you don’t.
Answers
1) Incorrect. The emphasis has not been built up enough to show that the following exclamation is important. It should be:
“I want to visit Florida for two important reasons: the sun and the atmosphere.”
2) Correct! It sets up the emphasis in the right way.
3) Incorrect. Again, no emphasis. It should be:
Please bring four things: clothes, shoes, bags, and makeup.
4) Incorrect. For the same reason above. Try this instead:
You’ll need these key ingredients: orange juice, lemonade, and ice.
5) Correct! You could also decide for yourself whether ‘Sometimes’ should have a capital letter or not. In American English you can decide either way, in British English it shouldn’t have a capital letter.