“Displays have separate Spaces” on Mac: what it does and when to turn it off
One checkbox changes how your menu bar, Dock, full-screen apps and Spaces behave across monitors. Here's what each choice does.
If you use more than one monitor on a Mac, one setting decides a lot about how they behave: Displays have separate Spaces. It's on by default. People usually find it while trying to fix something else, like a menu bar that's missing on one screen or a window that won't stretch across two.
Where to find it
- Open System Settings and click Desktop & Dock.
- Scroll down to the Mission Control section.
- Turn Displays have separate Spaces on or off.
- Log out and back in. The change doesn't apply until you do.
On vs off
| On (default) | Off | |
|---|---|---|
| Spaces | Each display has its own set of Spaces. Swiping changes only the screen you're on. | Spaces span every display. Switching a Space switches all screens together. |
| Menu bar | On every display. The one on the active display is brighter. | Only on the main display. |
| Dock | Can move to any display: push the pointer to the bottom edge of that screen. | Stays on the main display. |
| Full-screen apps | Take over one display. The others keep working. | Take over the main display. The other displays are left with nothing useful on them. |
| Windows across two screens | A window shows on one display at a time. | A window can stretch across displays. |
When to turn it off
- You need one window across two monitors. A long timeline in a video editor or audio workstation, a big spreadsheet, or a presentation spread over a display wall.
- You want your screens to act as one big desktop. Some people prefer switching every screen at once when they change Spaces.
For everyone else, leave it on. Full-screen apps, a menu bar on every screen and independent Spaces are worth more than stretching windows.
It doesn't change where your typing goes
Even with separate Spaces, there's still only one key window across all your displays, and it's the one that gets your keystrokes. The brighter menu bar tells you which display has it. Turn to another screen and start typing, and your words still go to the window you last clicked, possibly on a different screen.
That's the problem Glance Switch solves. It uses the camera to notice which screen you're facing and moves keyboard focus there, bringing forward the last window you used on that screen. It works with either setting, and with Spaces and full-screen apps. More on the underlying problem in why you keep typing into the wrong window.
Common questions
Where is “Displays have separate Spaces” on a Mac?
Open System Settings → Desktop & Dock and scroll to the Mission Control section. The switch is there. You need to log out and back in for a change to take effect.
Should I turn off “Displays have separate Spaces”?
Only if you need one window to stretch across two monitors, or want Spaces to switch on all displays together. For most multi-monitor setups, leaving it on works better.
Why does my menu bar only show on one monitor?
“Displays have separate Spaces” is off. Turn it on and log out and back in, and every display gets its own menu bar.