A guide comparing Associated Press style and Chicago style for editors, writers, teachers, students, word nerds, and anyone else who gives a dollar sign, ampersand, exclamation point, and pound sign about style.

Commas in a Series

In a series of three or more items, is there a comma before the conjunction? For example, which is correct?
  • I like to pet kittens, puppies and bunnies.
  • I like to pet kittens, puppies, and bunnies.

Before fists start flying, let me say that, in my experience, there appears to be a clear divide between two camps with regard to the serial comma: "highbrow" publications in one corner and, in the comma-hating corner, newspapers and most of my friends.

I conducted a poll with a deliberately skewed sample of literature to prove my point, and here are the results:

Serial comma:

No serial comma:

Variety made up its own language—excuse me, slanguage—so maybe it made up its own rules for punctuation as well. And we wonder why there are so many errors in ad copy.

Here's what AP and Chicago have to say.

AP (p. 366): What? A comma where? No. Absolutely not. Well, sometimes.
  • I like to pet kittens, puppies and bunnies.
  • I had orange juice, toast, and yam and kegs for breakfast. 
(Note: This is the cruelty-free version of AP's classic "ham and eggs" example.)

Chicago (6.18): Hells, yeah! Bring it.
  • I like to pet porcupines, pufferfish, and cacti.
  • I had rocks, glass shards, and sticks and stones for breakfast.

In short, AP's stance is to omit the serial comma except when it prevents misreading, and Chicago's stance is to always include it . . . for the same reason. Chicago, being twice as long as AP, has twice as much to say on this subject and offers several more variations of proper serial-comma usage on which the AP is mum (6.18–6.21).


  1. Well, Strunk & White prescribes the comma, and we all know that S & W kicks ass.

  2. Joe is right.

    I learned on Chicago, prefer Chicago by far, and so far have been required to use AP for every single one of my freelance proofreading/editing/writing jobs. Which is just a teensy bit annoying. But oh well.
    Great site by the way. It's cool to know someone else out there actually does give a dollar sign, ampersand, exclamation point, and pound sign about style.

  3. The final comma is needed when faced with sentences like this:

    "To my parents, Ayn Rand and God."
    (Book dedication)

    "Among those interviewed were his two ex-wives, Kris Kristofferson and Robert Duvall."

  4. I've been to law school and seen cases of the entire meaning of a contract paragraph thrown off because the final serial comma was not used. That's why I follow Chicago, and figure AP doesn't know what it's talking about in this case.