Serial Comma in Business Writing

Mary Cullen
Post by Mary Cullen
Originally published June 12, 2009, updated October 20, 2022
Table of Contents
Table of Contents

In nearly every business writing course I lead, the subject of whether or not to use a serial comma (also called an oxford comma) comes up. There are always strong opinions.

I actually dreaded writing this article. I was scarred by this subject while in graduate school studying composition and rhetoric when I had to write a 10-page paper on the history and merits/detriments of the serial comma. I had to present my research and opinion to my classmates, who not surprisingly loved to debate grammar. The argument about whether the serial comma should or should not be included lasted over two hours. We never did come to any consensus. 

This controversy probably exists because there is no grammar “rule.” Just convention. And, style guides differ. 

To define: a serial comma is the optional comma used at the end of a list. The most common conjunctions in a list are “and” and “or.” The serial comma is the comma that comes before the conjunction:

I like cookies, cupcakes(,) and gumdrops. (The comma before and is the serial comma.)

TED Talks provide an excellent illustrative summary:

Let me tip my hand and give you my opinion on this business grammar issue, and then I’ll explain why:

  • The customary convention in business writing is to use the serial comma.
  • The customary convention in journalism is to omit it, historically to conserve space.
  • British writers tend to use serial commas less than American writers.
  • It is both correct to use or not use a serial comma, so what is most important is consistency. (Be prepared for some editors to correct you, regardless of which option you choose.)

I recommend using the serial comma in business writing since it is the customary convention. To me, it is much easier to consistently follow this convention than to omit it most of the time and add it in when clarity is needed. Keep it simple.

Let’s look at examples where the serial comma clarifies:

When stocking your desk, be sure you have pens, pencils, paper clips(,) and pins. (The comma after pens in parentheses is the serial comma.)

If you do not use a serial comma in this sentence, meaning is still quite clear, but you might wonder if you need to buy a box of paper clips and pins mixed together:

When stocking your desk, be sure you have pens, pencils, paper clips and pins.

Let’s examine a more ambiguous example:

The job involves restocking shelves, cleaning and serving customers. (Without a serial comma before and, the sentence suggests the person doing this job will be responsible for cleaning the customers in addition to serving them.)

Another example illustrating confusion that results from omitting the serial comma:

“To reduce stress, I like running, yoga, meditation and visualization and quiet time alone.” Notice I omitted the serial comma here. Let’s see how this example works:

  • No comma: To reduce stress, I like (running,) (yoga,) (meditation and visualization and quiet) time.
  • Comma: To reduce stress, I like (running,) (yoga,) (meditation and visualization,) and (quiet) time.


Use the serial comma consistently in your business writing. 

Grammarians love to debate this issue, and there will never be full agreement, but for business writing, the convention is clear: use the serial comma.


Mary Cullen
Post by Mary Cullen
Originally published June 12, 2009, updated October 20, 2022
Mary founded Instructional Solutions in 1998, and is an internationally recognized business writing trainer and executive writing coach with two decades of experience helping thousands of individuals and businesses master the strategic skill of business writing. She excels at designing customized business writing training programs to maximize productivity, advance business objectives, and convey complex information. She holds a B.A. in English from the University of Rhode Island, an M.A. in English Literature from Boston College, and a C.A.G.S. in Composition and Rhetoric from the University of New Hampshire.