Few punctuation marks confound as much as one that should be one of the simplest, the colon. Use of the colon has many writers scratching their heads. It’s either not used when it should be, or used way more often than it should be. Normally, it’s the last thing a writer will even think about, because there are so many more important elements that take priority. But when giving the written document a final read-through, it can be one of those irritating obstacles a writer just can’t get around.

That said, the colon actually has very clear uses.

In general writing, it goes after an independent clause that precedes a list, or separates an explanation or example from an independent clause that precedes it.

The first use is one of the most common. An independent clause is a clause that can stand by itself as a sentence. So a list that comes after an independent clause would be one that comes after a stand-alone sentence to elaborate on what was said.

Jen’s favorite fruits were all citrus: grapefruit, oranges, lemons, and tangerines.

The next use also involves an independent clause. That is, an example or explanation that comes after the clause.

The rules of the game were simple: Don’t let anyone take your flag.

So, those two general uses of the colon follow the same premise. The colon is used when an independent clause is followed by something specific to that clause, rather than other punctuation marks that are used in more complex sentence structure.

Another major <Use of the colon>use of the colon is for an introduction to a topic. This includes things like a salutation in a business letter, or a date or lead-in item in a resume, author’s biography, or CV. It’s also used in reference formatting in academic papers, and to separate hours from minutes in the time of day, Biblical citations, and other similar, very specific instances.

In essence, the Use of the colon is pretty straightforward.

If it is not being used for one of the examples given above, it should not be used.

For instance, many writers use colons in dialogue as a substitute for attribution.
Instead of:
Mary said, “Start the car”
They say:
Mary said: “Start the car.”

This is not proper punctuation and this type of use should be avoided.

In an academic paper, most of your colons should be in your references. If they are sprinkled liberally throughout the text of the paper, you should refresh yourself on Use of the colon.

Knowing these rules becomes very important when the document you are writing is meant to impress, for instance an academic paper or a letter querying a job posting. When writing something that will either be judged by others, or that is intended to gain something from the target audience, it’s very important to know punctuation rules and usage, even something seemingly as minor as Use of the colon.

A professional editor is a great resource if the rules on Use of the colon are just one more thing that you know is going to trip you up when you are finishing up that academic paper and trying to remember all the other important elements that you need to make it a success.

A professional editor is versed in the Use of the colon, as well as all the other punctuation rules and big-picture elements that need to be followed in order for your paper to be a success, or for you to get that job, or grant, or scholarship.

That second set of eyes, one that not only knows the rules of punctuation and English usage, but can also follow the style guide for the institution or journal you are writing for, or know the professional style that letter should be written in, is the most valuable resource you will use in your writing project.