The Great Comma Debate: When to Use an Oxford Comma


Are you new to the Great Comma Debate? Are you a firm believer in the usage of the Oxford comma or do you think it’s a waste of space and ink? The Great Comma Debate has been raging in academia for over a hundred years, and it still has yet to be settled. Hopefully, our brief explanation and examples below will provide you with a good sense of when to use the Oxford comma in your lists–and when not to.


What is the Oxford Comma and When Should it Be Used?

The Oxford comma, also known as the serial comma, is the final comma that comes before “and” (or “or”) at the end of a list. For example:

The study shows that the patients enjoyed reading, knitting, and cooking.

The use of the Oxford comma is completely stylistic. The Associated Press (AP) style, used by American journalists, does not require the use of the Oxford comma, so the above example sentence would be written as follows:

The study shows that the patients enjoyed reading, knitting and cooking.

Generally, whether to include the Oxford comma or not is up to the writer. However, not including the Oxford comma can sometimes lead to misunderstandings caused by ambiguity. For example:

This research is dedicated to my professors, Angela and Samuel.

In this example, the research could be dedicated to two professors: one named Angela and one named Samuel; or it could be dedicated to multiple professors as well as to two people named Angela and Samuel. Omitting the Oxford comma will likely lead readers to believe that whatever items come after the comma (here, “Angela and Samuel”) is defining the item(s) presented before the comma (here, “professors”). If the research is dedicated to the writer’s professors in addition to two people named Angela and Samuel, using an Oxford comma tells the reader that these are three separate people or groups of people to whom the writer wants to dedicate their research.

This research is dedicated to my professors, Angela, and Samuel.

As demonstrated in the above example, one comma makes a crucial difference in meaning. Therefore, using the Oxford comma can eliminate ambiguity by showing the separation between list items.

Again, the choice is yours, but make sure that whatever convention you decide on, you are consistent throughout your writing. Some journals and publications have specific guidelines for how commas should be applied, so reading a lot of articles from your target journal or publication can be a good way to see how commas and other formatting and punctuation marks should be applied.

To ensure that your paper is free of errors in punctuation, formatting, and grammar, rely on Wordvice’s qualified editors and proofreaders, who can help you by proofreading for consistency as well as for grammar, spelling, and content. We have over 500 editors from 2,000 academic subdisciplines and assign your academic paper to the most qualified editor with a background in your paper’s subject area. Check out our top-notch academic editing services and see what professional proofreading and editing is all about.


Wordvice Resources

APA In-Text Citation Guide for Research Writing
How to Write a Research Paper Introduction 
Writing the Results Section of a Research Paper
Which Verb Tenses to Use in a Research Paper
How to Write an Abstract for a Research Paper
How to Write a Research Paper Title
Useful Phrases for Academic Writing
Common Transition Terms in Academic Papers
Active and Passive Voice in Research Papers
100+ Verbs That Will Make Your Research Writing Amazing
Tips for Paraphrasing in Research Papers


Additional Resources

Rules for Comma Use (Grammarly)
Using Commas, Colons, and Semicolons within Sentences (GrammarBook)
Rules for Using Semicolons (University of Wisconsin Writing Center)
How to Use the Em Dash (The Punctuation Guide)