What is the difference between V.O. and O.S. in a script?

V.O. (voiceover) means the speaker is not part of the scene's physical space — a narrator, inner thoughts, or a voice on a recording. O.S. (off-screen) means the speaker is physically present in the scene but not visible in the current shot, like someone talking from the next room.

How do you format voiceover in a screenplay?

Write the character's name in the cue as usual, followed by (V.O.) on the same line, then the dialogue below it. Example: SARAH (V.O.) followed by the line she narrates.

Is a phone call V.O. or O.S.?

The character we can see and hear is normal dialogue. The person on the other end of the line, whom we hear but don't see, is usually formatted as (V.O.) because they are not in the scene's physical space. If you cut to their location, they become on-screen there.

Voiceover (V.O.) vs. Off-Screen (O.S.): The Ultimate Formatting Guide

V.O. vs O.S. explained with examples. Learn the exact difference between voiceover and off-screen dialogue and how to format each one in a screenplay.

Few formatting details trip up new screenwriters as reliably as V.O. versus O.S. They look similar, they sit in the same spot next to a character's name, and they're constantly mixed up. But they mean different things, and using the wrong one tells a reader you haven't learned the craft. Here's the clear version.

The one-line difference

V.O. = Voiceover. The speaker is not in the scene's physical space. Narration, inner thoughts, a voice from a recording or a memory.
O.S. = Off-Screen. The speaker is physically in the scene but not in the current frame. They're in the next room, behind the camera, just out of shot.

The test: Is the character actually in this location right now? If yes but we can't see them → O.S. If no, they exist outside the scene entirely → V.O.

How to format each

Both extensions go on the character cue line, in parentheses, after the name:

                    NARRATOR (V.O.)
          She never saw the second car coming.

                    MOM (O.S.)
          Dinner's ready!

In the first, a narrator speaks over the picture — not in the scene. In the second, Mom is really in the house, just in another room.

Common cases, decided

Narration over a scene → (V.O.). The narrator isn't physically there.
Inner thoughts → (V.O.). Thoughts have no physical source in the room.
A character in the next room → (O.S.). They're in the location, off-frame.
A voice on the phone (we don't cut to them) → (V.O.). They aren't in this space.
A voice on the phone (we cut to their location) → normal dialogue in their scene; they may be (O.S.) to your scene if heard through the speaker but unseen.
A radio, TV, or intercom voice → (V.O.). The source is a device, not a person in the room.

Why it matters beyond pedantry

These tags are instructions for production. A sound team schedules V.O. as booth recording done separately; O.S. lines are captured on set with the scene. Get them wrong and you create confusion in the breakdown and on the day. Precise formatting isn't fussiness — it's how the page communicates to the crew.

Let the software place it

You shouldn't be indenting cues by hand. A proper screenwriting tool applies the character-cue element and lets you drop in (V.O.) or (O.S.) cleanly, every time. That's part of how Scriptease handles formatting — standard elements applied automatically so you can focus on which extension is right, not where it goes on the line.

For the full set of rules, see our guide to screenplay format.