Also known as O.S. · OS
A character who belongs in the scene’s space but is not visible in the shot — calling from another room, speaking just out of frame. Marked as (O.S.) on the cue.
On the page
Off-screen
JORDAN (O.S.)
You coming or what?
O.S. keeps geography honest: someone belongs in this scene's space but is not in picture -- down the hall, behind a door, just out of frame. It is different from narration (V.O.) and different from cutting to the other end of a phone call as its own live location with a full slugline.
A common mistake is marking every unseen phone voice as O.S. when the speaker is not actually in the location. If the other party is across town, you are usually in V.O., OVER PHONE, or an intercut -- not off-screen. Wrong extensions confuse who is physically present for staging and sound.
Use O.S. when the hide-and-reveal of the body matters: a threat in the next room, a parent calling from upstairs, a laugh we cannot place yet. Once the character steps into frame, drop the extension on the next cue so the page tracks visibility as clearly as the camera will on the day.
If we stay on one side and hear the other party through the phone, writers vary -- many use OVER PHONE or treat it as V.O. Stay consistent. If we cut between both locations, prefer intercut scenes.
Yes, if they remain present in the space but unseen -- locked in a closet, calling from the bathroom. If they leave the location entirely, end their presence cleanly rather than stretching O.S. past geography.
O.C. (off camera) appears in some TV traditions with a similar job. Pick the convention your draft already uses and stay consistent so actors and ADs are not translating synonyms mid-scene.
No -- put it on the character cue as an extension. Parentheticals are for delivery or small business, not for whether the speaker is visible in the shot.