How to Use Colons

Colons

Rule 1a. Use a colon to introduce an item or a series of items.

You know what to do: practice.
You may be required to bring many things: sleeping bags, pans, utensils, and warm clothing.
I want the following items: butter, sugar, and flour.
I need an assistant who can do the following: input data, write reports, and complete tax forms.

Rule 2. Avoid using a colon before a list if it directly follows a verb or preposition that would ordinarily need no punctuation in that sentence.

Not recommended: I want: butter, sugar, and flour.
Recommended: I want butter, sugar, and flour.
OR Here is what I want: butter, sugar, and flour.

Not recommended: I’ve seen the greats, including: Barrymore, Guinness, and Streep. Recommended: I’ve seen the greats, including Barrymore, Guinness, and Streep.

Rule 3. When listing items one by one, one per line, following a colon, capitalization and ending punctuation are optional when using single words or phrases preceded by letters, numbers, or bullet points.

If each point is a complete sentence, capitalize the first word and end the sentence with appropriate ending punctuation.

Otherwise, there are no hard and fast rules, except be consistent.

I want an assistant who can do the following:

1. input data
2. write reports
3. complete tax forms

The following are requested:

• Wool sweaters for possible cold weather.
• Wet suits for snorkeling.
• Introductions to the local dignitaries.

These are the pool rules:

1. Do not run.
2. If you see unsafe behavior, report it to the lifeguard.
3. Did you remember your towel?
4. Have fun!

Rule 4. A colon instead of a semicolon may be used between independent clauses when the second sentence explains, illustrates, paraphrases, or expands on the first sentence.

He got what he worked for: he really earned that promotion.

If a complete sentence follows a colon, as in the previous example, authorities are divided over whether to capitalize the first word. Some writers and editors feel that capitalizing a complete sentence after a colon is always advisable. Others advise against it. Still others regard it as a judgment call: If what follows the colon is closely related to what precedes it, there is no need for a capital. But if what follows is a general or formal statement, many writers and editors capitalize the first word.

Remember the old saying: Be careful what you wish for.

Rule 5. Capitalize the first word of a complete or full-sentence quotation that follows a colon.

The host made an announcement: “You are all staying for dinner.”

Rule 6. Capitalize the first word after a colon if the information following the colon requires two or more complete sentences.

Dad gave us these rules to live by: Work hard. Be honest. Always show up on time.

Rule 7. If a quotation contains two or more sentences, many writers and editors introduce it with a colon rather than a comma.

Dad often said to me: “Work hard. Be honest. Always show up on time.”

Rule 9. Use a colon rather than a comma to follow the salutation in a business letter, even when addressing someone by his or her first name. (Never use a semicolon after a salutation.) A comma is used after the salutation in more informal correspondence.

Dear Ms. Rodriguez:

Dear Dave,