Even if you’re not familiar with the term “comma splice,” you’ve most likely come across them in both classic and modern literature. They may even have pulled you out of a story for a moment, making you think, That doesn’t look quite right.

Comma splices are common, and tend to cause small speed bumps in an otherwise smoothly-paced story. And when you’ve worked so hard at engaging your reader through character, plot, and setting, the last thing you want is a persnickety grammar detail unraveling your hard work.

In this article we’ll give you an easy comma splice definition, along with ways to fix them when they slither uninvited into your writing.

What is a comma splice?

A comma splice is when two independent clauses—in other words, two short, standalone sentences—are separated by a comma. For example:

  • He just put on the kettle, it’s boiled already.

  • Dress warmly, it’s supposed to rain later.

  • I’m going to Paris, I can’t wait to see the Louvre.

  • I just watched the new release, it’s not what I expected.

Each of these sentences are made up of two small, complete sentences (or clauses) separated by a comma—they are comma splices.

Comma splices are bad because while the reader can generally understand what the clauses are trying to say, when spliced together they read awkwardly and unnaturally. Since a comma splice joins two independent ideas together, it can make it hard for a reader to understand the point you’re trying to make. It also makes it unclear to the reader what the connection is that you’re trying to make between the two clauses in a comma splice.

To create a really clear and elegant sentence, a comma should only be used to join an independent clause with a dependent clause. (A dependent clause is a sentence fragment that can’t function by itself.) For example, this sentence uses a comma correctly:

When he arrives, tell him I had to leave early.

“Tell him I had to leave early” is an independent clause, while “When he arrives” is a dependent clause. In the example above the comma is used correctly, and we haven’t created a comma splice because we didn’t join two independent clauses.

Comma splices vs. run-on sentences

Comma splices happen when two independent clauses are joined with a comma. Run-on sentences are very similar, but instead of using a comma to join two independent clauses, they use no punctuation at all. For example:

I just watched the new release it’s not what I expected.

In this example, “I just watched the new release” and “It’s not what I expected” are each independent clauses – they can stand on their own as complete sentences. But, we’ve joined them together, without punctuation. This results in a run-on sentence, which makes the reader feel like one sentence is “running on” right into the next one without pause.

How to fix a comma splice

Now that we know what a comma splice is in a sentence, let’s look at ways you can fix them so that your prose reads smoothly.

1. Use a conjunction

Conjunctions are little words that bridge two sentences together. There are two types of conjunctions: coordinating conjunctions and subordinate conjunctions. Even though the terms may look scary, you’ll probably know which to use instinctually just by looking at what the sentence is trying to say.

Coordinating conjunctions take two independent clauses and link them together to become one sentence. These are words like and, but, yet, so, and so forth. For example:

He just put on the kettle, yet it’s boiled already.

A subordinating conjunction is a kind of word or short phrase that not only links two clauses together, but it clarifies the relationship between them for the reader. This might be something like because, since, although, unless, etc. For example:

Dress warmly, because it’s supposed to rain later.

The second half of the sentence gives new information about the first half, and we’ve fixed the comma splice.

You’ll notice that by adding a conjunctive word to the comma splice, you’ve turned one of the independent clauses into a dependent clause. “Because it’s supposed to rain later” is no longer a standalone sentence; it’s a modification of another sentence. This is how you can tell that the comma splice has been punctuated correctly.

2. Use em-dashes

An em-dash looks like a long hyphen (although they’re not quite the same thing!) and, in punctuation, accomplishes quite a lot. One thing you can use em-dashes for is linking two independent clauses together to avoid the dreaded comma splice. For example:

Dress warmly—it’s supposed to rain later.

Like a subordinating conjunction, an em-dash precedes a sentence that contributes new information about the first one. In a story, this reads like a last-minute addition, or a new thought compounded onto the first one.

3. Use semicolons

A semicolon looks like a cross between a comma and a colon, and it’s used to join two independent clauses that share a related idea. It functions like a middle ground between a comma and a period—not quite one long sentence, but not quite two short ones, either. For example:

I’m going to Paris; I can’t wait to see the Louvre.

The semicolon creates a pause between the two independent clauses, but shows that they are related to the same thought.

4. Create isolated sentences

Sometimes the best option is to simply cut the sentence apart and let each one become a sentence of its own. You do this by closing the first independent clause with a period, and then starting the next one with a capital letter, like normal. For example:

I just watched the new release. It’s not what I expected.

Using a period instead of a comma will also speed up the pacing of your story by making your sentences seem shorter and punchier.

How to fix comma splices in your story

The best defense against comma splices is knowing how to recognize them in your writing. Once you know what to look for, you’ll be able to snag them and use one of the easy fixes we looked at above.

The solution you choose for one comma splice might be different than the best solution for another comma splice, depending on what sort of rhythms you’re using in your story and what it needs in that moment. Let’s look at our fixed comma splice examples again:

  • He just put on the kettle, yet it’s boiled already.

  • He just put on the kettle—it’s boiled already.

  • He just put on the kettle; it’s boiled already.

  • He just put on the kettle. It’s boiled already.

  • Dress warmly, because it’s supposed to rain later.

  • Dress warmly—it’s supposed to rain later.

  • Dress warmly; it’s supposed to rain later.

  • Dress warmly.

  • It’s supposed to rain later.

  • I’m going to Paris, and I can’t wait to see the Louvre.

  • I’m going to Paris—I can’t wait to see the Louvre.

  • I’m going to Paris; I can’t wait to see the Louvre.

  • I’m going to Paris.

  • I can’t wait to see the Louvre.

Now that we’ve fixed them, none of these sentences are grammatically incorrect; however, you can see that some definitely read better than others and may be better suited to different circumstances. When you’re editing your manuscript and looking for comma splices, try a few different solutions and see which feels like the best fit for your story.

Examples of comma splices in literature

Alas, comma splices have made their way into many novels and short stories over the years, even by professional writers. Here are a few comma splice examples from popular fiction:

1. “Hub Fans Bid The Kid Adieu” by John Updike

The air was soggy, the season was exhausted.

This sentence creates a vivid image of a late-summer day, but it feels incomplete. The reader’s instinct is to read it as “The air was soggy, the season was exhausted, and…?” If you’re writing a sentence like this one, consider other ways to link these two standalone thoughts together.

2. “A Report in the Spring” by E. B. White

By day the goldfinches dip in yellow light, by night the frogs sing the song that never goes out of favor.

E. B. White uses contrasting repetition—“By day” and “by night”—to give his language a more poetic, lyrical quality. This looks better than Updike’s sentence because the comma works as a hinge between two complementary ideas, although this particular structure may have worked better in a poem than in a prose essay.

3. A Tale of Two Cities by Charles Dickens

It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair, we had everything before us, we had nothing before us…

The opening to one of Charles Dickens’ greatest novels has become one of the most renowned opening lines in history. Like E. B. White, Dickens uses contrast to create an engaging picture of his story’s setting. This conscious stylistic choice works effectively in this instance, although it would begin to strain the reader’s eyes if it went on for very much longer.

Are comma splices ever acceptable in writing?

As you can see, even established writers are guilty of using comma splices. But does that mean it’s okay for us to use them too?

In general, there are better alternatives to comma splices. John Updike’s sentence may have read a bit smoother with a conjunction like and instead of a comma. E.B. White’s sentence looks a little better, though he may have reconsidered and used a semicolon if he had written it today.

Charles Dickens created one of literature’s most famous opening paragraphs by sticking so many comma splices into it that it began to look like a hedgehog. This was a style choice on his part—can you imagine how hard it would be on the eyes if it was slammed full of semicolons, or worse, em-dashes? Using commas to separate each sentence is technically incorrect, but the artful repetition of each phrase lends the opening paragraph a feeling of poetic rhythm.

Sometimes, comma splices can be useful in creating a natural “stream of consciousness” style narrative in a story. That might not follow conventional grammar, because our thoughts don’t always follow conventional grammar rules. Stylized comma splices might look something like this:

How much flour do I need, it was two hundred grams wasn’t it, next break the eggs, mix everything for how long, three minutes it says, the phone’s ringing but I can probably call them back, I wonder if he’s asked her to the dance yet, maybe I’ll wear that green dress if it still fits, how long has it been I forgot to check the time, did I remember the baking powder…

Note that stream of consciousness style writing can be difficult to read, and even more difficult to write effectively. We recommend avoiding it unless you’re certain you know what you’re doing.

There are rules to writing, but part of what makes writing an art is how writers creatively break those rules. But if you’re going to break the rules of grammar and storytelling, make sure you’ve considered each alternative and consciously chosen to break them because it was the right choice for your story in that moment, and not because you simply didn’t know the difference.

Keep comma splices at bay to clarify your writing

Comma splices are a pesky evil that can arise in the work of even the most experienced writers. When used with intention and precision, they can be used to create effective rhythms in a story; used unintentionally, however, and they stick out and disengage the reader. Make sure you know the rules of comma splices to keep your writing as sharp as it can be.