For those who are not familiar with the Oxford comma, it’s the serial comma. It comes after the penultimate item in a series and before the “and”:
The cat ate tuna, chicken, and cheese.
The comma after “chicken” is the Oxford, or serial, comma. Several heavy-hitting style and grammar books agree:
- The Chicago Manual of Style (CMOS), 16th Edition, strongly recommends using a serial comma to avoid ambiguity.
- Strunk & White’s The Elements of Style (4th Edition) clearly states that a serial comma should be used.
- Amy Einsohn’s The Copyeditor’s Handbook (2nd Edition) cites several other stylebooks that require the serial comma: WIT, APA, and CBE.
- Grammar Girl
The only stylebook I’ve come across that doesn’t use the serial comma at all times is the Associated Press Stylebook, but even then, it recommends using the serial comma when necessary to avoid ambiguity in longer list items:
My son ate his lunch of chicken nuggets and grapes, drank his milk, washed his hands very thoroughly, and then went upstairs for his nap.
I don’t understand the reasoning behind omitting that last comma, even in short lists. Newspapers did it to save space. Some argue that it’s confusing or unnecessary to use the last comma. I strongly disagree. The serial comma adds consistency, clarity, and just feels right to me, which is why so much of what I write has that extra comma. It’s all throughout this website and in anything I write that doesn’t require AP Style. CMOS is pretty much my own personal style guide, despite my journalism background.
I’ll always argue in favor of clarity, but I’m only one person, and I can’t take on the Associated Press. So if I’m not writing a press release or article for you, expect the Oxford comma.