Troubleshooting & messages · Free space and clean-up messages
What does "Held by your Mac for files you've already deleted" mean?
Short answer: Your Mac's automatic local backups still hold your deleted files, so deleting more won't free space. It returns on its own, or ask your Mac to release it from Local Snapshots.
Your Mac keeps short-lived automatic backups (local snapshots). They still hold the files you deleted, so that space doesn't come back straight away — and deleting more files won't help, because those get held too.
The space returns on its own as the backups age out, usually within a day. If you need it now, Storage Studio can ask your Mac to release it from the Local Snapshots section — without losing anything you still have.