Few punctuation marks start as many arguments as the Oxford comma. Here's what it is, why people use it, and how to decide.

What is the Oxford comma? #

It's the comma before the final and or or in a list of three or more items. It's also called the serial comma.

  • With: I bought apples, bananas, and oranges.
  • Without: I bought apples, bananas and oranges.

Both are correct. It's a style choice.

Why many writers use it #

It can prevent confusion:

I'd like to thank my parents, Taylor Swift and God.

Without the Oxford comma, this sounds like your parents are Taylor Swift and God. With it, the list is clear:

I'd like to thank my parents, Taylor Swift, and God.

Who uses it #

  • Usually yes: most American book publishers, The Chicago Manual of Style, APA style, and many businesses.
  • Usually no: AP style (used by many American newspapers) and a lot of British journalism, except when it's needed for clarity.

The real rule: be consistent #

Pick one style and use it everywhere in the same document. Switching back and forth looks careless.

When you always need it #

Even writers who skip the Oxford comma add it when a list item contains and:

Breakfast options are toast, eggs, and bread and butter.

Check your lists #

AI Grammar Checker reviews commas in your lists and sentences, so your punctuation stays clear and consistent.