What are Extensions in Screenwriting? (The Complete Guide)

Screenwriting Extensions

What are extensions in screenwriting? Extensions in screenwriting are abbreviations written by the writer on the right side of a character’s name in a screenplay to indicate where a character is talking from. 

There are two screenwriting extensions:

Extensions AbbreviationsMeaningWhen to use Them
When the speaking character is in the room but isn’t seen by the camera. Sometimes replaced by (O.S.)
V.O.Voice OverIn every other case, this extension is used, for example, heard voices, voicemails, T.V’s, radio, narrations, flashbacks, you name it.
screenwriting extensions

How to Format Screenwriting Extensions

How do you format a screenwriting extension? You format a screenwriting extension by capitalizing the abbreviations of O.S. or V.O. surrounded by parentheses next to the character’s name.

Most screenwriting software will auto-populate this when hitting space after writing the character’s name.


John (V.O.)
I never knew what she really meant my that.

Example 2:

John (O.S.)
The time she came I didn't know what she really meant. 

Examples of Screenwriting Extensions in Screenplays

Below we have two examples of extensions used in a screenplay written by Tod Philips.

In this example, you can see they didn’t use the periods. My guess is because this is a production draft script where the typical screenwriting quarks aren’t a bother. After all, the producer trusts the writer.

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Happy writing.

What are Extensions in Screenwriting? (The Complete Guide)
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