What Is the Oxford Comma?

If you’re a grammar nerd, you probably already have strong opinions about the Oxford comma.

If you haven’t heard of it, the Oxford comma isn’t a big deal, despite the fancy name that evokes grammarians looking down on your less-than-perfect essay. Here’s everything you need to know about the Oxford comma.

The Oxford Comma Revealed

The Oxford comma is just another name for a regular old serial comma. You already know that when you list items in a sentence, you separate them by commas. For example:

I need to add flour, milk, and sugar to the grocery list.

The comma before the word “and” is the Oxford comma.

The tricky part about the Oxford comma is that the Oxford Comma is completely optional. Whether you use the Oxford Comma or not is really up to you.

That means that you can write the sentence two ways, and both are correct:

I need to add flour, milk, and sugar to the grocery list.

I need to add flour, milk and sugar to the grocery list.

The first sentence uses the Oxford comma while the second does not use the Oxford Comma. Either is a viable option in the writing community.

It’s a Matter of Style – Choosing What to Teach Students About the Oxford Comma

The only time that there’s a real rule about whether or not to use the Oxford comma is when you’re writing according to a particular style guide for publication. For example, The Associated Press (AP) style guide insists on cutting out the Oxford comma, presumably so that newspapers didn’t waste ink or space on unnecessary punctuation. Their argument is that the Oxford comma adds nothing to general comprehension and can therefore be omitted. You’ll see this streamlined style in use in almost every newspaper, and it tends to be the default style of internet publications as well.

On the other hand, plenty of publishers do require the Oxford comma in their style guides. Many magazines use the Oxford comma, and you’ll often see it in books. Many academic writing styles also require the Oxford comma, most notably the Modern Language Association (MLA). This is typically the style schools require for research papers, so it makes sense to teach students the Oxford comma now. The habit of using the Oxford comma will serve them well in most of their writing assignments in secondary school and college.

Using the Oxford Comma to Clear Up Confusion

There are certain times when using an Oxford comma does more than just make the sentence look prettier. That extra bit of punctuation can also help to erase some ambiguity in sentences. For example:

My favorite people are my cousins, Abraham Lincoln and Harriet Tubman.

This sentence does not use the Oxford comma, and it can be read two ways. Are you interpreting this sentence to mean that the writer has at least four favorite people, including two or more cousins, the sixteenth president of the United States and the leader of the Underground Railroad? Or do you see that the writer has just two favorite people, his distant cousins Honest Abe and Harriet Tubman?

In this case, skipping the Oxford comma leaves open some hilarious unintended meanings. It’s easily fixed by adding the Oxford comma for clarity:

My favorite people are my cousins, Abraham Lincoln, and Harriet Tubman.

That Oxford comma leaves no room for doubt about how the writer is related to Lincoln and Tubman: as a distant admirer only, and not as a blood relative.

Teach Your Students to Be Consistent

From a teaching standpoint, it’s probably easier to simply encourage regular use of the Oxford comma as a way to eliminate that type of ambiguous statement altogether. A good rule of thumb is to ask for consistency: If your students want to use the Oxford comma, they should be sure to do so every time. It’s only when writers slide back and forth between styles that missing the Oxford comma looks like a mistake.

Learn more about grammar rules and download a number of worksheets to help improve your student’s writing!