Semicolon Vs. Colon: What Is the Difference? Learn Common Mistakes

The semicolon vs. colon debacle can be an intimidating one when you’re writing. When broken down to its most basic usage, a semicolon separates an independent clause when two independent clauses exist in a sentence.

A colon or a semicolon can be used to separate two independent clauses when the second independent clause is closely related to the content and subject matter of the first clause. And a colon is used to separate items in a list in text.

All of this may seem like a lot to remember and confusing, but as long as you know and understand the few rules that exist for these punctuation marks, it’s easy and will become second nature to use correctly in writing. This article will explain all of the rules of each punctuation in more detail.

The Semicolon

A semicolon can be used at the end of an independent clause when two independent clauses exist in one sentence or when either sentence can stand on its own as a complete sentence. These complete sentences can stand by themselves if you put a period between them instead of a semicolon.

The semicolon also functions as a replacement for a conjunction. The following are a few examples of this rule at work.

Example:

Country and western music and folk music are my least favorite genres of music; they make me think of the festivals my grandparents dragged me to when I was a kid. 

In the example above, a semicolon has been used because it separates two independent clauses, either of which could be a complete sentence. Observe that rule applied in the following example.

Example:

Country and western music and folk music are my least favorite genres of music. They make me think of the festivals my grandparents dragged me to when I was a kid. 

In the above example, the same words have been used, but instead of a semicolon, a period has been placed at the end of the first independent clause to make a new sentence. This has occurred to break up what was a very long sentence, and because there were two independent clauses present, neither sentence needed to be reworded or changed to make these two new sentences make sense. You can also separate the independent clauses with a conjunction.

Example:

Country and western music and folk music are my least favorite genres of music because they make me think of the festivals my grandparents dragged me to when I was a kid. 

In the above example, the coordinating conjunction “because” has taken the place of any punctuation mark, and one long sentence has been created.

Conjunctive Adverbs

When two phrases or clauses are separated by adverbs used to connect them, you can use a semicolon in place of a period. This is used to continue one thought without having to pause. Observe the following example:

Example:

Abigail thought that Steven would ask her to the Prom; much to her surprise, though, Steven asked Kaitlyn to the dance instead. 

The Colon

The colon is a direct, punchy punctuation mark that demands your attention. Often misused, some people think that if you use a semicolon to separate two independent clauses, then you’d use a colon for a dependent clause, but that is a big grammar and writing mistake.

To Separate Two Independent Clauses

Just like the semicolon, the colon can be used to separate and create a pause after two independent clauses. The colon does so with much more dramatic flair, though. Note the following example.

Example:

Don’t take the elevator to the lobby: the stairs are the better option. 

Don’t take the elevator to the lobby; the stairs are a better option. 

Both of the above sentences are punctuated correctly, and they state the same thing. However, the first example that uses the colon is more direct. It’s more an order than a request. You’re most likely going to take the stairs because you’re being told to.

Semicolon Vs. Colon

In the second sentence example, a semicolon was used, and the flow of the sentence was much more conversational and informal. You might take the stairs after reading that sentence because it’s been gently suggested.

Only Capitalize If A Proper Noun Follows the Colon

Sometimes you see the word following the colon in a capitalized sentence, which can create some confusion. When a colon is present, especially when it’s been used to separate clauses, you might want to capitalize the first word after the colon because it could stand as its own sentence. This is a common mistake.

When used to separate two clauses, the first word after a colon should only be capitalized if the word is a proper noun. Note this in the following example:

Mark’s favorite band took no time for him to decide: Metallica. 

Cindy’s favorite vacation destination has been the same for her entire adult life: Myrtle Beach. 

In the first above example, “Metallica” is the name of a band, and therefore a proper noun. In the second example, “Myrtle Beach” is the name of a place and is therefore in need of capitalization.

These punctuation marks are used often in academic writing, so it is vital that when they are used, they are used correctly.

Use a Colon Between Two Separate Sentences

When the second clause in a complex sentence can stand on its own and is related to the first clause, you can use a colon. You can also keep the sentence together and complex by placing the word “and” where the colon would go.

Or, you can split the sentence entirely and put a period where the colon could go. You can also use a semicolon in this instance. It’s a lot to remember, but once you have it down and committed to memory, it’s not difficult at all.

In a Formal Letter

You can use a colon when addressing someone in a letter that is of a formal nature. It would take the place of a comma. Note the following example.

Example:

Dear Sir or Madam:

To Whom It May Concern:

Dear Resident:

Dear Student: 

When Listing Things

If you are writing a story, and it includes a list, a colon should be used. For example, if you have a character in a story who is going to the grocery store, they may need multiple items. You would separate those items at the grocery store in your text with a colon so that the sentence is not confusing. An example of the proper use of a colon to show a close relationship between things listed follows.

Example:

Clint was most interested in the Social Sciences: Economics, Sociology, Psychology, and Criminology. 

Common Colon Mistakes

Mistakes are made more often with colons than with semicolons. The following are a few of the most common mistakes.

Mistake #1: Using a Colon to Separate Sentences That Aren’t Related

The second clause has to directly relate to subject matter and content for a colon to be the appropriate punctuation to use. Otherwise, the last clause needs a semicolon, a period, or a conjunction. Colons are used when the clauses of a sentence are too related to one another to be separated into two sentences. Adding the colon creates one detailed sentence rather than two choppy ones.

Mistake #2: Skipping the Colon When Quoting with Multiple Sentences

Often in a novel or book, the author will quote another work. When the quote is lengthy or several sentences long, you should bypass the use of a comma and use a colon instead. This is done to draw attention to the fact that there is a long quote being cited.

Mistake #3: Using a Capital Letter Consistently After a Colon

You only need to capitalize the first word after a colon when the word following the comma is a proper noun and could stand as its own sentence.

Why Not Just Use a Comma?

When you have long compound sentences, it can be tempting to employ the trusty comma, out of concern for your own self-interest, especially if the semicolon or colon confuses you. However, only using the comma instead of an occasional semicolon creates long, rambling sentences that don’t always give us a complete thought.

Semicolon Vs. Colon

Em Dashes

Em dashes (—) are perhaps the most versatile and multi-faceted of all the punctuation marks. When you use an em dash, it can be for several purposes. The following are some ways you can use an em dash:

  • To replace colon use for added effect
  • To interrupt
  • To change the subject in text or dialogue
  • To denote omissions in the text either by intentional redaction or because the information missing isn’t known.

The em dash is a double dash rather than a single dash. A single dash is an en dash and is nowhere near as versatile as the em dash.

A Quick Recap

The following are tips and rules about semicolons and colons that you can use as a quick reference.

  • When you need more separation than what a comma provides but don’t want to use a period, use a semicolon.
  • A colon can be used to separate two complete thoughts that are closely related.
  • You can use a semicolon where most people use a comma to separate phrases and thoughts to boost your writing and a bit more sophistication.
  • Don’t overuse colons, semicolons, or dashes.
  • A colon can be used to introduce information. Only use it to introduce information if it is related in content to the phrase before it.
  • Words that come after the colon only need a capital letter if they are a proper noun. All other words are correct without capitalization.
  • Use semicolons and colons when your writing has too many commas to break up the phrases and make the reading more understandable.
  • Use a colon to introduce a long quotation.