About Time Machine local snapshots

Time Machine lets you restore files from local snapshots of the files on your Mac, even when your Time Machine backup disc isn't available.

Your Time Machine backup disc may not always be available, so Time Machine also stores some of its backups on your Mac. These are local snapshots.

How to use local snapshots

When your backup disc isn't available, Time Machine uses local snapshots automatically to help you restore files. Reconnect your backup disc to make even more backups available.

Find out how to restore files from Time Machine

How often local snapshots are saved

Time Machine saves one snapshot of your startup disc approximately every hour, and keeps it for 24 hours. It keeps an additional snapshot of your last successful Time Machine backup until space is needed. And in macOS High Sierra or later, another snapshot will be saved before installing any macOS update.

How local snapshots use storage space

You don't need to think about how much storage space local snapshots are using, because they don't use space needed for tasks such as downloading files, copying files or installing new software. In fact, your Mac will count the space used by snapshots as available storage.

Even so, Time Machine only stores snapshots on discs that have plenty of free space and it deletes snapshots automatically as they age or as space is needed for other things.

If you want to delete local snapshots manually, turn off automatic backups temporarily:

  1. Open Time Machine settings:

    • Choose Time Machine settings (or preferences) from the Time Machine menuNo alt supplied for Image in the menu bar.

    • Or in macOS Ventura or later, choose Apple menu  > System Settings, click General in the sidebar, then click Time Machine on the right.

    • Or in macOS Monterey or earlier, choose Apple menu  > System Preferences, then click Time Machine.

  2. Turn off automatic backups in Time Machine settings:

    • In macOS Ventura or later, click Options, choose Manually from the "Back up frequency" pop-up menu, then click Done.

    • In macOS Monterey or earlier, deselect ”Back Up Automatically", or use the Off/On switch, depending on what you can see.

  3. Wait a few minutes to allow local snapshots to be deleted. Then turn on automatic backups again. Time Machine will remember the backup disks it was using.

Published Date: