The vast majority of writers make errors when punctuating the dialog in their novels. Many writers who make these errors think they have a firm grasp on dialog punctuation.
Though it probably won’t get you rejected by an agent or editor, incorrect punctuation can put them in a very nasty mood (the last thing you want when they’re handling your precious novel).
Commas
Commas are always used with dialog tags, whether they come before or after the dialog. For example:
“Look at the dog,” he said. [RIGHT]
He said, “Look at the dog.” [RIGHT]
“Look at the dog.” He said. [WRONG]
He said. “Look at the dog.” [WRONG]
If an exclamation point or question mark is used and the dialog tag comes after the dialog, then there should be no comma and the dialog tag should not be capitalized. For example:
“Did you see the dog?” he asked. [RIGHT]
“Did you see the dog?” He asked. [WRONG]
Dialog Tags
Writers are often confused about what qualifies as a dialog tag. A dialog tag is only something that references the way the words came out of the character’s mouth. Any gestures, expressions, movements, etc. should be set apart from the dialog with a period, not connected with a comma. For example:
“Look at the dog,” he exclaimed. [RIGHT]
“Look at the dog,” he smirked. [WRONG]
“Look at the dog,” he pointed. [WRONG]
He jumped up and down, “Look at the dog.” [WRONG]
And despite what many writers seem to think, you cannot laugh or sigh dialog.
“Oh, bother,” she sighed. [WRONG]
“Oh, bother,” she said, sighing. [RIGHT]
“Look at that cute puppy,” she laughed. [WRONG]
“Look at that cute puppy.” She laughed. [RIGHT]
If the dialog tag is in the middle of a character speaking, then the dialog is not capitalized after the tag unless it starts a new sentence. For example:
“I was thinking,” she said, “that maybe you could teach me.” [RIGHT]
“I was thinking,” she said, “That maybe you could teach me.” [WRONG]
“I love that dog,” she said. “He’s so cute.” [RIGHT]
“I love that dog,” she said, “he’s so cute.” [WRONG]
Interrupted Dialog
If the dialog is interrupted by another character speaking, use an em dash. For example:
“It’s not fai-”
“Shut up!” he said. [RIGHT]
“It’s not fai . . .”
“Shut up!” he said. [WRONG]
Trailing Dialog
If a character trails off, an ellipsis should be used. Despite what many people think, an ellipsis is only three periods. For example:
“I just thought maybe . . .” [RIGHT]
“I just thought maybe…………” [WRONG]
Multiple Paragraphs of Dialog
If your dialog needs to run multiple paragraphs without dialog tags breaking it up, then each paragraph that is not the last paragraph should have no quotation mark at the end of it. For example:
“My dear, sweet Love. I love you so much that I can barely take it. You are the sun and the moon and the stars to me and you always will be.
“Unless, of course, you betray me, then I will cut off your head and put it on a stake,” he said. [RIGHT]
Ellen Brock 
This is a great, succinct post on dialogue! Very helpful.
Reblogged this on Tessa Bertoldi and commented:
There were several discussions on the proper use of dialog at the SFWC this year. Many new authors struggle with it. I will be sure to put this on my editing checklist! Good advice.
Reblogged this on Cindy D and commented:
And more on Dialogue – I found this blog by The Write editor – Enjoy!
Thank you! VERY helpful!
Awesome! I’m so glad!
Thank you for taking the time to do this!
Ellen, one stop shopping for dialogue punctuation! Thank you so much!! I needed this and didn’t even know it. It makes me wonder how many other punctuation errors I make. I shudder to think . . .
I’m so glad it helped!
Reblogged this on Just 4 My Books and commented:
This is the most useful guide that I have found on dialogue 🙂 I can’t recommend these lectures highly enough. You have to check them out for yourselves – NOW!!!
> “Unless, of course, you betray me, then I will cut off your head and put it on a stake,” he said.
This sentence is not quite grammatically sound; “then” ought to be replaced with “in which case” or an equivalent phrase. This is because the sentence lacks a clause that could stand as an independent sentence, and instead each half (“unless…” and “then…”) grammatically depend on the other half.
This is an example of dialogue. People do not speak with perfect grammar. If you try to use perfect grammar in your dialogue, it will seem extremely unnatural.
Hello! This article was such a good read! But I just have one more doubt! Are dialogues in a dialogues alright?
Like for example:
Tim broke the silence. He said, “Mom went crazy, last night. She started screaming “Fire!” and ran around the house.”
Because I want to emphasise that Tim tried to mimic the way his mom said fire. I’m guessing dialogues in a dialogues don’t work. But do you have any advice on how I can convey Tim’s action?
Thank you and have a pleasant week ahead!
“Fire!” in your example should be in single quotation marks: ‘Fire!’
I hope this helps!
So something like this is wrong (referring to the dialog tag section that dialog tag should be something that only mouth made.)
“So how’s our project doing?” he asked from the toilet.
If it’s incorrect, then what’s the right one?
There’s nothing wrong with what you’ve written. “He asked” is the dialogue tag. “From the toilet” is just the location.