The Hidden Bandwidth Drain
macOS is designed to make upgrading to the next major operating system version as frictionless as possible. To achieve this, your Mac will silently download massive update files (often 12GB to 14GB in size) in the background while you are working. While you still have to click “Install” to actually apply the update, the sheer act of downloading it can completely choke your home Wi-Fi network, causing Zoom calls to stutter and web pages to load slowly. Furthermore, if you have a MacBook with a small 256GB hard drive, this massive installer file will sit silently on your disk, eating up precious storage space.
How to Disable Automatic Background Downloads
You can configure macOS to only download these massive files when you explicitly tell it to, giving you total control over your network bandwidth and hard drive space.
1. Click the Apple logo () in the top-left corner of the menu bar.
2. Select System Settings (or System Preferences on older versions).
3. In the left-hand sidebar, click on General.
4. In the main pane, click on Software Update.
5. Look for the section labelled “Automatic Updates” and click the small “i” icon (information button) next to it.
6. A new dialog box will appear with several toggle switches.
7. Locate the toggle switch labelled Download new updates when available.
8. Click the toggle switch to turn it Off.
9. Click Done (you may be asked to authenticate with Touch ID or your password).
Keeping Security Responses Active
When you disable automatic downloads, you are also disabling automatic feature updates. However, it is highly recommended that you leave the toggle for Install Security Responses and system files turned On. These are incredibly small, targeted security patches that protect against zero-day exploits. They do not consume massive amounts of bandwidth or storage space, and keeping them automated is crucial for your Mac’s safety.