When the internal hard drive on your Mac drops below 20GB of free space, macOS begins displaying a persistent, unmissable notification: “Your disk is almost full. Save space by optimising storage.”
While this warning is well-intentioned, it becomes incredibly annoying if you are fully aware of your storage situation and are intentionally working with limited space (for example, if you are actively editing a massive video project that you plan to delete tomorrow). The notification will reappear every day, demanding your attention. If you want to silence this specific warning permanently, you can do so using a hidden terminal command.
How to Disable the Storage Warning via Terminal
You can tell the system daemon responsible for monitoring disk space to stop sending these alert notifications.
- Open the Terminal app on your Mac. (You can find it by pressing Command + Space and typing “Terminal”).
- Copy and paste the following exact command into the terminal window:
defaults write com.apple.diskspaced minFreeSpace 1 - Press Enter on your keyboard.
This command technically tells the operating system to only trigger the “disk full” warning when your free space drops below 1 Gigabyte, rather than the default 20 Gigabytes. Because macOS will typically crash or freeze long before it hits 1GB of free space, this effectively disables the notification entirely.
How to Restore the Default Warning
If you buy a larger hard drive or clear up enough space that you want the safety warnings to return, you can easily reverse the command.
- Open the Terminal app again.
- Type the following command and press Enter:
defaults delete com.apple.diskspaced minFreeSpace
This deletes the custom rule you created and forces macOS to revert to its default behaviour, ensuring you are warned when your drive drops below 20GB again.