How to enable automatic macOS updates

Why this matters

The vast majority of real-world macOS attacks target vulnerabilities that have already been patched — they work because users haven’t installed the patches. Apple ships security updates roughly monthly. If updates are manual, you’ll skip them when you’re busy, and the gap between disclosure and your install gives attackers a free window.

Automatic updates close that window for you, in the background, while you sleep. It is the cheapest meaningful security upgrade in this entire checklist.

How to do it

1. Open System Settings → General → Software Update.
2. Click the ⓘ next to Automatic Updates.
3. Turn on all four toggles:
   • Check for updates
   • Download new updates when available
   • Install macOS updates
   • Install application updates from the App Store
   • Install Security Responses and system files
4. Restart when prompted by future updates — don’t put it off more than a few days.

What you don’t need

You don’t need to manually download Security Updates from Apple’s website. The built-in updater fetches them automatically and verifies their signatures cryptographically.