Comma Rules or Guidelines

As promised, here is a list of comma rules, most of which will be discussed and explained. These are by no means exhaustive, but do cover 90% of what you will need. The truth is if you understand the “rules” or guidelines below, you will seldom struggle.


  • To separate non-critical words, phrases, and clauses from main clauses.
    Turning slowly, I gazed at the apparition that stood by the door.
  • Adding phrases to the end of a sentence to mark a distinct pause or shift.
    I stood frozen to the spot, while waves of trembling started washing over me.
  • Comments inserted into a sentence, and in these cases you need two commas to set it off.
    I tried to say something to the people in the other room, but, engrossed in their own search, they didn’t hear me.
  • When a conjunction (for, and, nor, but, or, yet, so) joins two independent clauses.
    I suddenly moved, and the apparition disappeared.
  • Separate three or more words, phrases, or clauses written in a series.
    I ran as fast as I could out the door, knocking over two glass lamps, a table, and three chairs as I went.
  • Introduce a quotation.
    I heard a voice say, “Good riddance!”
  • To separate two or more coordinate adjectives modifying a single noun.
    Heart-breaking, drawn-out sobs came from behind the couch.
  • Use a pair of commas to set off nonessential words, clauses, and phrases that come in the middle of your sentence.
    A young girl, no more than six or seven years old, eventually peeked out from where she had been hiding.

The only real guideline for when not to use commas is this:

  • Don’t use commas to set off essential words, phrases, or clauses.

Understanding commas is as much about when not to use as when to use them. So be ready.