Local snapshots

Your Mac keeps local snapshots, automatic backups of its own disk, so it can roll files back. They hold on to files you've since deleted or moved, which is why free space can lag behind a clear-up. The Local Snapshots screen shows every snapshot, tells you which ones are already safely on your Time Machine drive, and lets you remove them or release a set amount of space.

Open it from the More menu (•••) → Local Snapshots…, or from the Local Snapshots button in Storage Inspector.

Reading the screen

The header shows your Time Machine drive and the date of its latest backup, plus how much space the snapshots are holding that you can reclaim. If no Time Machine drive is set up, it says Time Machine destination not configured. and treats every snapshot as local-only.

Each snapshot shows how long ago it was taken and one of these:

macOS reports one combined size for all snapshots and none for a single one. The size on each row starts with ~ because it's that total split evenly, an estimate.

Freeing the space

%% caption: The three ways to release space from local snapshots
flowchart TD
  A[Local Snapshots screen] --> B{What do you want?}
  B -->|Remove one snapshot| C[Delete on its row, then confirm]
  B -->|Remove all already backed up| D[Delete all backed-up, type Delete to confirm]
  B -->|Free a set amount| E[Custom reclaim: choose GB, Reclaim now]
  E --> F[macOS removes old snapshots until that much is free]
  C --> G[Space released]
  D --> G
  F --> G

• Delete on a row removes that one snapshot after a confirmation that tells you whether it's backed up.
• Delete all backed-up removes only snapshots already copied to your Time Machine drive. Snapshots not yet backed up, and the ones macOS needs for updates, are left alone. Because it removes several at once, you type Delete to confirm, then click Delete permanently.
• Custom reclaim lets you enter a number of gigabytes and click Reclaim now. macOS then removes old snapshots until that much space is free. It decides which ones; you can't ask for more than the snapshots are holding.

Removing a local snapshot can't be undone from inside Storage Studio. It doesn't touch the backups on your Time Machine drive.

Space from past moves

If folders you've moved to your external drive still haven't shown up as free space, a banner says how much freed by past relocations may still be pinned, with a Reclaim button for that amount. It asks macOS to release old snapshots until that space comes back.

Elsewhere in the app

• Smart Care includes Reclaim old local backups when there's something to reclaim, and reports it separately from freed space, because macOS already counts that space as available.
• Emergency Space offers Release space held by automatic backups first, because it deletes nothing you still have.
• Storage Inspector's Space held by backups section shows each snapshot's age and whether macOS marks it as one it can clear by itself.

See also: Why deleting files doesn't always give the space back · Storage Studio and Time Machine · Restore Points · Purgeable space