Figuring out when to put a comma before “and” in a list can be confusing.
If you have looked at various sentences that contain lists, you have probably seen that sometimes there is a comma before “and” and sometimes there is not.
Worse, if you have tried to figure out when you do or don’t need a comma by comparing those sentences, you probably got even more confused.
Most likely, you didn’t see anything consistent about the sentences to help you identify when to use a comma.
Do you need a comma before “and” in a list?
Whether or not you need a comma before “and” in a list depends on two things. The first thing is the style you are writing in (Chicago, MLA, APA or Oxford style), which varies depending on the type of document that you are writing. The second thing is the clarity of the sentence. If you are writing in a style that does not normally require a comma before “and” in a list, there may still be sentences in which the meaning is unclear without a comma before “and.” In those cases, you should include the comma even when the style does not normally use it. You may see the comma before “and” in a list referred to as the Oxford comma or the serial comma.
Commas before “and” in sentences with lists
First, let’s take a look at a few examples of the kinds of sentences we are talking about.
All of these sentences contain a list, but why do the last two have a comma before “and” when the first one does not?
The answer is style and clarity.
In the first two sentences, whether or not to use the Oxford comma is a matter of style. The sentences have the same meaning with or without the final comma.
In the third sentence, a comma would always be needed regardless of style for reasons of clarity. If you remove the comma, the meaning of the sentence becomes unclear.
We’ll discuss this more below.
What is a”style guide”?
Usually, when people talk about “writing style,” they mean the various techniques the writer uses.
However, in this case, “style” means the guidelines that the writer is following. In some cases, when it comes to grammar, spelling, punctuation and capitalization, the rules are flexible.
Different professions have different guidelines for these rules to ensure editorial consistency.
Chicago, MLA, APA and Oxford styles
The major styles in which you are supposed to put a comma before “and” are Chicago, MLA, APA and Oxford. The first three are American, and Oxford is British.
MLA is an academic style used for topics in the humanities, such as literature. APA is also an academic style, used for education, psychology and science.
Chicago, sometimes called Turabian, is usually what commercial book publishers use. It is also common in fine arts, history and business.
The name “Oxford comma” comes from its use in the “The Oxford Style Manual.” Oxford style is used by Oxford University Press and a number of international organizations.
The most widespread style that does not require a comma before “and” in a list is AP style. AP style is the default style for American journalists, so you will usually see American newspapers omit the comma.
There are cases when whatever style you are writing in, you will need a comma for clarity.
Let’s look back at one of the example sentences from above:
You can tell from reading this sentence that the writer is going to tell several people: some cousins and Frank and Alice.
However, let’s look at what happens if you remove the serial comma:
There are two ways to interpret this sentence.
One is that the writer is going to tell their cousins plus Frank and Alice. The other is that the writer is only going to tell two people, their cousins, whose names are Frank and Alice.
You can see why if the meaning is the former one, it is important to use the comma to make that clear.
Here’s another example. Let’s look at a sentence written with and without the comma before “and”:
Do you see the difference in the meaning between two sentences that having or not having the comma creates?
In the first sentence, the generous donation will result in hundreds of new jobs in both Los Angeles and at the Humane Society.
In the second sentence, the project will involve three separate things.
The Humane Society is involved as is a generous donation, but the job creation is only happening in Los Angeles.
When you aren’t using a style guide
After reading all this, you might be wondering, “But what if I’m not a journalist or writing a paper for school? What if I just want to write an email or a social media post? Do I use the comma then?”
The answer is that unless it is an issue with clarity, it’s entirely up to you.
Just be forewarned that although it may sound surprising, some people are very passionate about whether or not to use the Oxford comma!
A few more things about the comma before “and”
Many professions use one of the major standardized styles guides, such as AP or Chicago. However, note that many newspapers, magazines, organizations and government bodies have their own style guides with their own rules about whether to use this comma.
The comma before “and” is more common in American English than it is in British English—despite the fact that it is often called “the Oxford comma.”
However, you cannot entirely rely on this since some American style guides recommend against using the comma and some British style guides recommend using it.
In sentences with list items that contain commas themselves, the items should be separated by semicolons, and there should be a semicolon before “and.” This is necessary for clarity.
Here’s an example:
Hey fellow Linguaholics! It’s me, Marcel. I am the proud owner of linguaholic.com. Languages have always been my passion and I have studied Linguistics, Computational Linguistics and Sinology at the University of Zurich. It is my utmost pleasure to share with all of you guys what I know about languages and linguistics in general.