• 2-minute read
• 17th July 2014

The Serial/Oxford Comma

The Oxford comma can be a useful tool in writing, as it can help make lists much clearer. Some style guides also demand its usage. In this post, we will explain how and when to use it.

How to Use the Oxford Comma

Also known as the serial comma, or the series comma, the Oxford comma is a comma placed before the final ‘or’, ‘and’, or ‘nor’ in a list. It is called because its use is recommended in the style guide of the Oxford University Press. It would be used like this:

The colours of the Australian flag are red, white, and blue.

In the above sentence, a comma before the final ‘and’ isn’t strictly necessary, since there is not much room for confusion in the sentence. Adding it is therefore just a matter of style.

In some cases, however, an Oxford comma is necessary to avoid confusion with a list. This applies when, without one, the final two items in a list could be mistaken for specifications of the preceding one. Take, for example, the following sentence:

I’d like to thank my teachers, my mother and Charles Dickens.

Here, without an Oxford comma, the reader might assume that the writer’s teachers are his/her mother and Charles Dickens. An Oxford comma would clarify this:

I’d like to thank my teachers, my mother, and Charles Dickens.

Now we can see that the writer is definitely listing three separate things.

In some cases, reorganising the items in the list is enough to resolve the ambiguity. For instance, the sentence above could be written like this:

I’d like to thank my mother, my teachers and Charles Dickens.

If, in a list, the first word is a plural and the following two are singular, consider rearranging them to make your meaning clear.

In summary, the Oxford comma is useful for clarifying your meaning when using lists. However, some style guides suggest that it shouldn’t be used. In these cases, rearranging the sentence is usually a better choice.