How to Set Up Hot Corners to Trigger Your Mac Screen Saver

Every time you step away from your desk at the office, you should lock your Mac’s screen to prevent unauthorized access to your emails and files. While you can use the keyboard shortcut (Control + Command + Q) or navigate to the Apple logo in the menu bar to lock the screen, both methods require a moment of conscious effort. macOS includes a brilliant, highly underutilized accessibility feature called “Hot Corners” that allows you to instantly trigger your screen saver (and subsequently lock your Mac) simply by flicking your mouse cursor into one of the four absolute corners of your monitor.

How to Configure Hot Corners

Setting up a Hot Corner takes less than a minute and requires no third-party software.

1. Click the Apple Logo in the absolute top-left corner of your menu bar.
2. Select System Settings from the dropdown menu (or System Preferences on older macOS versions).
3. Scroll down the left-hand sidebar and click on Desktop & Dock.
4. Scroll to the very bottom of the main pane and click the Hot Corners… button.
5. A dialog box will appear showing a tiny representation of your monitor with four dropdown menus, one corresponding to each corner of the screen.
6. Decide which corner you want to act as your trigger (the bottom-left or bottom-right corners are usually best, as the top corners are often accidentally triggered when reaching for menus).
7. Click the dropdown menu for your chosen corner (e.g., Bottom Left).
8. Select Start Screen Saver from the list of options.
9. Click Done to save your changes.

Now, to test it, simply aggressively drag your mouse cursor all the way down into the bottom-left corner of your screen. The screen saver will instantly activate without you needing to click anything.

Ensuring the Screen Saver Actually Locks the Mac

Activating the screen saver only protects your privacy if macOS is configured to actually demand a password when waking back up. If it is not configured correctly, someone could just wiggle the mouse and bypass the screen saver entirely.

1. Return to the main System Settings window.
2. Scroll down the left sidebar and click on Lock Screen.
3. Look for the setting labeled: Require password after screen saver begins or display is turned off.
4. Click the dropdown menu next to it and select Immediately.

With this final setting in place, your new Hot Corner becomes a flawless security tool. The second you stand up from your desk, flick your mouse into the bottom-left corner. The screen saver engages instantly, and the Mac locks down, requiring your fingerprint (Touch ID) or password before anyone can resume using it.