Posted by & filed under Editing, Effective Writing, Punctuation and Grammar.

People frequently are unsure whether to put a comma before “and,” but how about using a comma before such words as because, when, where, and who?

 Essential clause – Words that are an integral part of the main thought of a sentence form an essential clause, and you should not set off this clause with a comma. An essential clause will begin with such words as although, because, if, when, where, whether, or who (they are called subordinating conjunctions, and there are 23 in all, but you don’t need to memorize them in time for happy hour conversation).

 Nonessential clause – When the information in the clause is not necessary to complete your main idea, insert a comma to separate it from the rest of the sentence.

 Here is the distinction, as it applies to because:

A. He was allowed access because he has security clearance.

B. She cannot meet on Friday, because of schedule conflicts and deadlines.


Sentence A – The clause because he has security clearance is considered essential to the main thought because if you said only that “He was allowed access,” the reader would wonder why. With a significant question unanswered, the thought would be incomplete, or at least, the sentence would seem oddly clipped.

 Sentence B – It is enough to say that she cannot meet on Friday. That’s all the reader needs to know. The reasons why provide extra explanation but are not necessary.

 Here is another example:

A. Jim will meet you at the ski lodge where the other racers plan to gather.

B. Jim will meet you at the ski lodge, where the other racers plan to gather.


Without the comma, sentence A indicates that the clause where the other racers plan to gather is essential; that is, it means there are several ski lodges, and Jim plans to meet you at the one where other racers will gather, not at the lodges where racers will not be gathering.

But most ski resorts only have one lodge, so B illustrates the correct punctuation, because the clause where the other racers plan to gather is nonessential. If you were to write only that “I will meet you at the ski lodge,” the reader would know exactly where to meet you, because there is only one lodge. So if the words are not necessary, insert a comma to set them off.


7 Responses to “Comma Uncertainty: When to Use it Before “Because””

  1. Lynda Lockhart

    My book was just professionally edited, and I noticed the ecitor placed a comma after every “because.” I alwzys thought non was necessary. Now I’m seeing that one is used with an unnecessary addition to the sentence. Is this true? Thank you, Lynda

  2. Ken O'Quinn

    Hi Lynda,
    I don’t know why an editor would insert commas after because, but it’s not unusual to have one before because. When the element (the clause or phrase) that begins with because is not essential to the main thought of the sentence, set it off with a comma. If I say, “I won’t be able to attend the luncheon, because I have all-day meetings and phone calls,” the comma after luncheon is appropriate. Most of the time, a comma before because is necessary. But it often is difficult to determine whether it is or isn’t essential. If you write, “The game was canceled because of the rain,” no comma is called for, because the last piece is essential to the meaning.
    Thanks for writing.

  3. Anthony Ayodele

    Ken, you said you didn’t know why an editor would place a comma after ‘because’, I guess it’s for the same reason you did in the first sentence of your answer to the question (laughs); I’m trying to find out whether I could get away with this: ‘Empty vessels make the most noise because, like a hungry bird waiting to be fed a worm by its mother or the person who quests for Success, they are the ones who yearn to be filled most! I had it published before giving it a second thought! What are your thoughts?

  4. Ken O'Quinn

    Anthony, in my answer to the previous question, the sentence in which I used because followed by a comma was a different context than the one the person was referring to. If the sentence says, It’s uncommon to use a comma after because, but it sometimes is appropriate, then the comma there is correct, because it separates complete thoughts. The comma that you have after because in your Empty vessels sentence is also correct. It sets off an element that is not part of the main thought.

  5. Miguelito

    Very cool. Thanks. Use a comma when the clause is not essential…
    I’m editing something important now and need that. I had always thought that there was supposed to be a comma before all “because”… I have to look at my hobby site to see how I handled it there.

Leave a Reply

Your email address will not be published. Required fields are marked *