The One Sentence That Absolutely Requires a Colon
Here's a sentence that makes grammar nerds swoon:
"There are three things I can't stand: people who chew loudly, people who don't indicate when turning, and people who say 'I could care less' when they mean 'I couldn't care less.'"
See that colon? Here's the thing — it's not stylistic. It's grammatically required. Think about it: it's not optional. And here's the wild part — it's one of the very few places in English where a colon is actually mandatory, not just preferred Surprisingly effective..
This is the sentence that needs a colon. On top of that, not can have one. Needs one.
What Is the Colon Rule, Exactly?
The rule comes down to this: you use a colon after a complete sentence (linguists call it an independent clause) that introduces a list. The colon signals to the reader: "What comes next is the list I just promised you."
The classic trigger words are "the following" or "as follows":
- "Please bring the following: a towel, sunscreen, and your sense of adventure."
- "The ingredients are as follows: flour, sugar, eggs, and butter."
But the version that really sticks in people's minds is the "three things" construction. Something about that specific phrasing — "There are three things I [verb]..." — feels like it demands a colon. And grammatically speaking, it does Small thing, real impact..
Why a Complete Sentence Matters
Here's what trips people up. So the colon isn't needed just because you're introducing a list. It's needed because you're introducing a list *with a complete sentence that could stand on its own The details matter here..
Compare these two:
- "I need to buy: apples, bananas, and oranges."
- "I need to buy apples, bananas, and oranges."
In sentence 1, "I need to buy" isn't complete. It's hanging, waiting for an object. That colon is actually incorrect there. The second version — no colon, just a list flowing naturally from the verb — is the right call.
Now compare:
- "I need to buy three things: apples, bananas, and oranges."
- "I need to buy three things, apples, bananas, and oranges."
Sentence 1 works because "I need to buy three things" is a complete thought. But the colon then says, "Here's what those three things are. " Sentence 2 is grammatically wobbly — you could get away with a comma there, but it feels less clear Took long enough..
This is the distinction that matters. On top of that, the colon isn't a decoration. It's a signal that says, "The introduction is done. Now here's the list.
Why Does This Matter?
Look, most of the time, punctuation is flexible. But you can get away with a lot. But this particular rule exists for a reason — clarity.
When you put a colon after a complete introductory sentence, you're doing two things:
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You're signaling structure. The reader knows the list is coming and knows it's directly tied to what came before. No confusion about whether "apples, bananas, and oranges" is a list or just examples floating around.
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You're following a convention that readers expect. This is the one place where most style guides — Chicago, AP, MLA — agree. When an independent clause introduces a list, use a colon. It's like a subtle nod to the reader that you know the rules.
And honestly? There's something satisfying about getting this one right. It's a small precision, but it signals attention to detail. Plus, it's one of those rules that's easy to remember once you see it: complete sentence + list = colon.
The "Following" Construction
The other place this comes up constantly is with "the following" or "as follows":
- "The requirements are as follows: a valid ID, proof of address, and a signed form."
- "Please note the following: the meeting is at 3 PM, not 2 PM."
These are complete sentences. They introduce lists. Here's the thing — they need colons. This is non-negotiable in virtually every style guide out there And it works..
How It Works: The Rule in Practice
Here's the formula:
Complete introductory clause + colon + list
The introductory clause must be able to stand alone as a sentence. If it can, and it's introducing a list, use a colon.
Some examples that work:
- "She had three goals: lose weight, save money, and learn Spanish."
- "The museum displays four permanent collections: art, history, science, and technology."
- "Bring these items: a pen, your ID, and the completed application."
Some examples that don't work (because the intro isn't a complete sentence):
- "To apply, you need: a resume, cover letter, and references." → Should be "To apply, you need a resume, cover letter, and references."
- "The best movies are: The Godfather, Casablanca, and Pulp Fiction." → Should be "The best movies are The Godfather, Casablanca, and Pulp Fiction."
When You Can Skip the Colon
There are times when you don't need a colon even with a list:
- After verbs that naturally take lists: "I bought apples, bananas, and oranges." No colon needed — the verb flows right into the items.
- In very short, informal contexts: "I need milk, eggs, and bread." A colon would feel stiff here.
- When the list is integrated into the sentence: "The colors red, white, and blue represent the flag." No colon — the list is part of the subject, not an introduction to something.
The colon is for when you're explicitly announcing a list. It's a spotlight, not a workhorse.
Common Mistakes People Make
Mistake #1: Using a colon after an incomplete sentence.
This is the most common error. People see a list and reach for a colon without checking if their intro is a complete sentence And that's really what it comes down to. Turns out it matters..
Wrong: "The ingredients include: flour, sugar, and eggs." Right: "The ingredients include flour, sugar, and eggs."
Mistake #2: Never using a colon when they should.
Conversely, some people avoid colons entirely, even when the sentence clearly calls for one.
Wrong: "Here are the options: coffee, tea, or water." (Wait, this one actually works with a colon! But some people would write "Here are the options, coffee, tea, or water" and it feels clunky.) Right: "Here are the options: coffee, tea, or water.
Mistake #3: Over-colonizing.
Some writers get so excited about the rule that they start coloning everything. Remember: the intro must be a complete sentence, and it must be introducing a list. Not every list needs a colon Still holds up..
Practical Tips for Getting It Right
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Read the intro clause on its own. Can it stand as a complete sentence? If yes, and it's introducing a list, add a colon.
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Listen for the pause. When you read the sentence aloud, does the intro naturally pause before the list? That pause is the colon telling you where to go.
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Watch for "the following" and "as follows." These phrases almost always need colons after them.
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Don't force it. If the sentence flows better without a colon, leave it out. Grammar serves clarity, not the other way around Not complicated — just consistent..
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Remember the "three things" sentence. It's the mnemonic device that sticks. "There are three things I love: X, Y, and Z." That colon is non-negotiable Simple, but easy to overlook..
FAQ
Does every list need a colon?
No. Only when a complete sentence introduces the list. Many lists flow naturally without colons: "I bought apples, bananas, and oranges.
What's the difference between a colon and a semicolon?
A colon introduces something (usually a list or explanation). A semicolon connects two independent clauses that are closely related. They're not interchangeable But it adds up..
Can I use a colon in informal writing?
Absolutely. Worth adding: if you're texting or writing casually and the sentence calls for it, use the colon. Which means it looks perfectly fine. You don't need to dumb down your punctuation.
What about bullet points? Do they need colons?
Often, yes. If your introductory sentence is complete, a colon before a bulleted list is standard: "Please bring the following:" then bullets below. But if the intro isn't a complete sentence, skip it.
Is this rule different in British vs. American English?
Not really. Both conventions use colons the same way in this context. The colon-after-independent-clause rule is pretty universal No workaround needed..
The Bottom Line
Here's the thing — most punctuation rules are suggestions. Style guides vary, context matters, and good writers break "rules" all the time when clarity demands it.
But this one? The colon after a complete sentence introducing a list? Here's the thing — that's a real rule. It's one of the few times English grammar draws a firm line.
So the next time you write "There are three things I love: [list]," know that you're participating in a small grammatical tradition. Practically speaking, that colon isn't optional. It's required. And now you know why.
