Should I put a comma before the last item in a list?

Question

Should I put a comma before last item in list?

I would like crackers, cheese and some soda.
I would like crackers, cheese, and some soda.

Answer 1

Using a comma before the last item in a list is known as the Oxford Comma, sometimes the Serial Comma. It is used before conjunctions in a list like this with three or more items. Its use is purely written style and optional. It is more common in America outside journalism, and much less common in other English speaking areas of the world. There are arguments for and against which usually come down to comprehension. Wikipedia quotes these ambiguities:

To my parents, Ayn Rand and God.

To my mother, Ayn Rand, and God.

Also on that wiki page you can find lots of links to certain style guides. Comma use is something of a grey area though, and everyone has his own style. Pick what reduces ambiguity.

Language log has an interesting article on how reading comprehension can be improved with comma use, including this type.

Answer 2

Not using that comma can lead to factual errors, as in the apocryphal book foreplate:

• Dedicated to my parents, Ayn Rand and God.

Answer 3

The basic question here is about disambiguation. Does the comma give you information that you need in order to fully understand the sentence? If it does, you want to include it. If not, it's not necessary, although it can still be used. It's common in the United States, not so much in the U.K.

In addition to the examples itrekkie listed, you could also consider this:

"I leave all my worldly possessions to my nieces Sarah, Jane, and Carol." This sentence implies that each niece would receive 1/3 of the estate.

"I leave all my worldly possessions to my nieces Sarah, Jane and Carol." This sentence could be read to imply that Sarah gets 50% of the estate, while Jane and Carol each get 25%.

Answer 4

Sometimes the serial comma is necessary to delineate the final two items in the list when the final item is a compound item (containing the word "and").

My favorite drinks are Long Island Iced Tea, Bloody Mary, vodka, and Jack and Coke.

...and:

My favorite drinks are Long Island Iced Tea, Bloody Mary, vodka and Jack and Coke.

I'm not sure if anyone really drinks a vodka+Jack+Coke, but it could happen!

Answer 5

The comma before the "and" is called an Oxford comma or a serial comma. Despite being called an Oxford comma, Brits don't commonly use it.

From Wikipedia:

Opinions vary among writers and editors on the usage or avoidance of the serial comma. In American English, the serial comma is standard in most non-journalistic writing, which typically follows the Chicago Manual of Style. Journalists, however, usually follow the AP Stylebook, which advises against it. It is less often used in British English.[4][5] In many languages (e.g. French,[6] German,[7] Italian,[8] Polish,[9] Spanish[10]), the serial comma is not the norm; it may even go against punctuation rules, but it may be recommended in some cases to avoid ambiguity or to aid prosody.

Answer 6

I, too, was taught never to use a Serial comma, but it is by no means solely an American thing to add the extra punctuation — the extra comma is actually frequently known as the Oxford comma, because it is the house style of Oxford University Press, one of the oldest and most influential publishers in the world.

I agree with Wikipedia on this issue — opinions on the use of the serial comma "vary among writers and editors."

In American English, the serial comma is standard in most non-journalistic writing, which typically follows the Chicago Manual of Style. Journalists, however, usually follow the AP Stylebook, which advises against it. It is less often used in British English. In many languages (e.g. French, German, Italian, Polish, Spanish), the serial comma is not the norm; it may even go against punctuation rules, but it may be recommended in some cases to avoid ambiguity or to aid prosody.

Answer 7

This is known as the serial comma. There is a whole discussion in Wikipedia about its usage in various style guides.

Answer 8

The latter example is known as the serial comma, Harvard comma or Oxford comma, these last two names coming from the style guides of Harvard University Press and Oxford University Press insisting upon it.

Opinion varies. If you are writing to a style guide then you should follow the rules placed upon you (Chicago Manual of Style insists upon it, while the Associated Press Stylebook advises against).

It's more common in America than Britain, but both styles are found throughout the English-speaking world.

There are a few cases where it can avoid ambiguity, but otherwise if you don't have a style-guide dictating on the matter, it's up to you.

Answer 9

Urban legend has tried to teach people that the comma before the "and" in this situation is optional, but it isn't. The legend of removing the comma originated back in manual typesetting days when newspaper print space was at a premium, and that particular comma became expendable. That's the origin of this errant "omission rule" that, I believe, has made it into the AP style book.

Answer 10

In my book Rules for Writers - Diana Hacker
It says:

When three or more items are presented in a series, those items should be separated from one another with commas. Items in a series may be single words, phrases, or clauses. Although some writers view the comma between the last two items as optional, most experts agree that it is better to put it in because its omission can result in ambiguity or misreading.

She provides an example:

The activities include a search for lost treasure, dubious financial dealings, much discussion of ancient heresies[,] and midnight orgies.

She comments:

Without the comma this sentence is easily misread. The people seem to be discussing orgies, not having them. The comma makes it clear that midnight orgies is a separate item in the series.

Answer 11

There is no need for a comma before and in such cases unless its omission creates ambiguity.

Answer 12

The preferred style in the US is to always use the serial comma; elsewhere, it is less common, particularly in the UK. Choosing not to use the serial comma has little benefit other than reducing the number of marks on the page, whereas its omission has two notable drawbacks.

1. More thinking required
2. Possibility of ambiguity if you make the wrong decision

As ever, the priority is consistency.

Answer 13

Think about this for a minute: what would it actually mean for using the comma here to be "right" or "wrong" and why would your teacher be the authority on this? Did your teacher have special exclusive access to a special 11th commandment on comma usage issued by God?

No.

What you're dealing with is a stylistic preference. There's no "right" and "wrong" here. What do you prefer or feel is more sensible (easier to read etc)? Or, where applicable, what does your editor/publisher's in-house style guide prefer to you to do in these cases?

If you are making the decision, that competing factors you might want to weigh up:

• people typically use a comma to represent a mid-sentence pause, and when reading lists like this, speakers often make a pause before the 'and';
• on the other hand, from a visual point of view, the 'and' already marks a separation between the last two items in the list, so from purely the point of view of separating items, the comma is a little redundant.

Which of these factors (and any others you might think of) do you feel wins out overall?