Colon to Introduce a List
Summary
Use a colon to introduce a list but only after a grammatically complete sentence. Don’t use a colon after a fragment or incomplete sentence.
- Incorrect: You will require:
Correct: You will require the following: - Incorrect: The nominees are:
Correct: The nominees are as follows: - Incorrect: Remember to:
Correct: Remember three things:
Within a sentence, use a colon only at the end of a complete independent clause (one that could stand by itself as a sentence). Don’t use a colon between a verb and its object.
- Incorrect: We need: a car, a map, and the open road. (colon between verb and object)
Correct: We need a car, a map, and the open road. (no colon at all)
Correct: We need three things: a car, a map, and the open road. (colon after independent clause)
Don’t use a colon after a list heading, title, or caption. Prefer to use formatting options (like bold or emphasis) to set off a heading from the rest of the text.
- Incorrect: Index:
Correct: Index
A colon may be used in a glossary to introduce a definition.
- LRR: long-range sensor
What is the colon?
The colon is a punctuation mark that directs attention to the information that follows. It is often used to introduce lists and quotations, and to amplify or explain a statement.
- You will need three things: a needle, some thread, and a steady hand.
- Don’t poke the dragon: it explodes!
- Follow these steps:
- Find the red button.
- Press it.
- When you hear a beep, start the machine.
In this article we discuss how to use the colon correctly to introduce a list, and how this punctuation mark can be used in lists in general.
Colon to introduce a list: The general rule
Use a colon at the end of a grammatically complete sentence to introduce a list.
- Correct: You will need the following ingredients:
- A slice of bread
- A pat of butter
- A pinch of Italian seasoning
- A slice of Parmesan cheese
- Correct: Pack emergency supplies: a flashlight, snacks, and a good book.
Don’t use a colon if the list is introduced by a fragment or incomplete sentence.
- Incorrect: Don’t:
- Try to pry open the doors.
- Panic.
- Break the emergency phone.
- Incorrect: The services we offer are:
- Flight bookings
- Hotel reservations
- Taxi bookings
- Holiday packages
A grammatically complete sentence comprises an independent subject, a verb, and expresses a complete thought.
- Incorrect: The species are:
Correct: The species are listed below: - Incorrect: We offer:
Correct: We offer the following services: - Incorrect: Watch out for:
Correct: Watch out for these insects: - Incorrect: Note:
Correct: Note these common errors:
In horizontal lists
In a horizontal list, use a colon only at the end of a complete independent clause (one that could stand by itself as a sentence).
- Incorrect: We sell: cupcakes, cookies, and candy.
Correct: We sell cupcakes, cookies, and candy.
Correct: We sell confectionary: cupcakes, cookies, and candy.
In formal writing, be careful not to incorrectly insert a colon in a sentence simply to highlight a list that follows. Either omit the colon altogether, or formulate a complete independent clause, place a colon after it, and then present your list.
- Incorrect: Bring: (1) a flashlight, (2) a book, (3) some chocolate, and (4) an extra pair of socks.
Correct: Bring a flashlight, a book, some chocolate, and an extra pair of socks.
Correct: Bring the following items: (1) a flashlight, (2) a book, (3) some chocolate, (4) an extra pair of socks. - Incorrect: Don’t forget to: turn out the lights and shut the door.
Correct: Don’t forget to turn out the lights and shut the door.
Correct: Don’t forget two important things: turn out the lights and shut the door. - Incorrect: The dragon was: smarter, stronger, and older than us.
Correct: The dragon was smarter, stronger, and older than us.
Correct: The dragon was impossible to beat: it was smarter, stronger, and older than us.
To identify an independent clause, check whether it can stand by itself as a sentence.
- Incorrect: We repair:
Don’t use a colon after a fragment.Correct: We repair all kinds of household appliances:
Don’t use a colon between a verb and its object.
- Incorrect:The services we offer include: car rental, flight booking, and hotel reservation.
The object of the verb include is “car rental . . .” Don’t use a colon between verb and object.Correct: The services we offer include car rental, flight booking, and hotel reservation.No colon between verb and object.Correct: The services we offer include the following: car rental, flight booking, and hotel reservation.The object of the verb include is “the following,” after which the list is presented.
A colon may be used after a word or phrase that introduces a list when the verb is omitted.
- Strengths: courage, confidence, intelligence. Weaknesses: pride, fear of public speaking.
- Pros: safety profile, space, fuel efficiency. Cons: speed, price, availability.
In vertical lists
To introduce a vertical list using a colon, write a grammatically complete sentence followed by the colon, and then present your list. Don’t use a colon after a fragment (or incomplete sentence).
- Incorrect: The chest contained:
- A spade
- A map
- A half-eaten candle
- A human skull
- Correct: The chest contained four things:
- A spade
- A map
- A half-eaten candle
- A human skull
- Incorrect: For a heavenly slice of moist chocolate cake:
- Find a good recipe.
- Buy the ingredients.
- Bring them together, carefully following your recipe. (You must know when to beat, when to fold, and when to just mix.)
- Pour the mix into a baking tray, and pop it in the oven. (Was it preheated?)
- Go back in time, and simply order online from us at the Quick-Cake Bakery.
- Correct: For a heavenly slice of moist chocolate cake, follow these steps:
- Find a good recipe.
- Buy the ingredients.
- Bring them together, carefully following your recipe. (You must know when to beat, when to fold, and when to just mix.)
- Pour the mix into a baking tray, and pop it in the oven. (Was it preheated?)
- Go back in time, and simply order online from us at the Quick-Cake Bakery.
It is not wrong to introduce a list using a fragment. This is often done when the entire list is laid out as a complete sentence. Just remember not to use a colon to introduce such a list.
- Correct: The chest contained
- a spade,
- a map,
- a half-eaten candle,
- a human skull.
Don’t place a dash after a colon to introduce a list.
- Incorrect: To hang a painting on a wall, follow these steps:—
Correct: To hang a painting on a wall, follow these steps:
This style of punctuation (a colon followed by a dash) is now archaic.
After headings, titles, and captions
Don’t use a colon after a list heading, title, or caption. Headings and captions are better styled using formatting options like font size, indentation, and emphasis (e.g., bold) rather than set off using a colon.
- Incorrect: Ingredients:
- 3 cups all-purpose flour
- 6 eggs
- 3 cups sugar
- 1 teaspoon baking powder
- 1 cup butter
- Correct: Ingredients
- 3 cups all-purpose flour
- 6 eggs
- 3 cups sugar
- 1 teaspoon baking powder
- 1 cup butter
- Incorrect: Hot beverages:
- Earl Grey
- Assam black
- Americano
- Cappuccino
- Flat white
- Correct: Hot beverages
- Earl Grey
- Assam black
- Americano
- Cappuccino
- Flat white
In a glossary
In a glossary or a list of definitions, use a colon to explain or define. The definition provided after the colon is usually capitalized.
- control group: The group we did not treat but observed.
- sum insured: The maximum amount of coverage provided under the policy.
A colon can also be used in a list of abbreviations to provide the full form of each abbreviation used in a document. Don’t capitalize the full form unless it is a proper noun.
- PFD: portable floating device
- SGS: small green space
- ESA: European Space Agency
Common mistakes
Watch out for these four common mistakes when using a colon to introduce a list:
1. Don’t use a colon after a fragment or incomplete sentence.
- Incorrect: You ordered:
Correct: You ordered the following items: - Incorrect: Use a colon:
Correct: Use a colon as follows:
2. Don’t use a colon in the middle of a clause.
- Incorrect: In the event of emergency: remain calm, proceed to the nearest exit, and leave the building in an orderly manner.
Correct: In the event of emergency, remain calm, proceed to the nearest exit, and leave the building in an orderly manner.
Correct: In the event of emergency, follow instructions: remain calm, proceed to the nearest exit, and leave the building in an orderly manner.
3. Don’t use a colon between a verb and its object.
- Incorrect: Please pack: a flashlight, a bar of chocolate, your favorite book.
Correct: Please pack a flashlight, a bar of chocolate, and your favorite book.
Correct: Please pack the following items: (1) a flashlight, (2) a bar of chocolate, (3) your favorite book.
4. Don’t use a colon after a title, heading, or caption.
- Incorrect: Dos and Don’ts:
Correct: Dos and Don’ts - Incorrect: Best Practices:
Correct: Best Practices
Usage guide
Use a colon after a grammatically complete sentence to introduce a list. Don’t use a colon after a fragment or incomplete sentence. Also don’t unnecessarily interrupt a sentence with a colon to present a list: a colon should only appear at the end of an independent clause. One way to know you are using the colon wrong is if it appears between a verb and its object. Avoid using a colon after a caption or a heading; use formatting options instead to set off the heading from the rest of text. Finally, in glossaries and lists of definitions, a colon can be used to present the definition or meaning of a word or a phrase.