Stop your Mac reopening old windows and documents

On a shared family Mac, a work machine you hand off, or any account more than one person touches, macOS window restoration is a quiet privacy leak. Quit an app, and it saves your open documents; reopen it — or let the next person reopen it — and there's your bank statement, your draft email, your medical PDF, right where you left it. Turning off restoration means apps open blank, and nothing private waits around for someone else.

Why restored windows are a privacy problem

macOS's Resume feature is built for convenience: it remembers each app's windows so your session picks up where it stopped. That's fine on a Mac only you use. But it makes no distinction between "you, later" and "someone else, next." If a partner, kid, or colleague opens Preview, TextEdit, or a document app after you, restoration cheerfully repaints whatever you had on screen. The file isn't reopened from a menu they'd have to find — it's just there. Switching restoration off removes that exposure without deleting anything or logging you out.

Turn off window restoration

One system-wide setting stops apps from saving and restoring their windows. Its label reads inside-out, but it's the correct switch for privacy:

1. Open System Settings → Desktop & Dock.
2. Scroll to the Windows section.
3. Turn on Close windows when quitting an application.

Now quitting an app discards its window state, so relaunching — by you or anyone — starts clean. It behaves identically on macOS 13 Ventura, 14 Sonoma, and 15 Sequoia. The Terminal equivalent, useful if you're locking down several Macs, is one line:

# Don't preserve windows on quit — nothing to restore for the next person
defaults write NSGlobalDomain NSQuitAlwaysKeepsWindows -bool false

# Undo — restore your session on relaunch again
defaults write NSGlobalDomain NSQuitAlwaysKeepsWindows -bool true

It applies to apps quit after you run it, so log out and back in to be certain every app forgets its last state. Nothing needs restarting.

The gaps to close alongside it

Window restoration is one door; a couple of others stay open on a shared account:

• The restart dialog. When you shut down or restart, uncheck Reopen windows when logging back in so a full reboot doesn't repaint everything either.
• Safari tabs. Safari keeps its own session no matter what you set above. Set Safari → Settings → General → "Safari opens with" to A new window, or browse in a Private window so nothing is saved to reopen.
• Recent Items. Even with windows gone, the Apple menu and app "Open Recent" lists still name your files. Clear them via the Apple menu → Recent Items → Clear Menu.

The real fix for a shared Mac

These settings keep your session from leaking, but the cleanest privacy boundary between people is separate accounts. If everyone shares one login today, giving each person their own user account — or the household a Guest account — means nobody's windows, documents, or tabs can spill into anyone else's session in the first place. Restoration off is the right move on any account; separate accounts are what make "shared Mac" and "private" stop being a contradiction.

Lock the screen when you step away

Restoration off protects the next login; a locked screen protects the moment you walk off. Pair this with requiring a password after sleep on Mac so no one reaches your session at all.