Start a Time Machine Backup Now with tmutil

tmutil startbackup kicks off a backup immediately — handy before system updates or big changes.

macOSbackuptmutiltime-machineLow risk

Run `tmutil startbackup` to begin a backup to the configured destination; abort with `tmutil stopbackup`.

01Command

Command

$ tmutil startbackup

02What it does

Time Machine backs up every hour only while the destination is reachable, which can leave important work unprotected for a long time. startbackup runs the same engine the automatic schedule uses, including incremental copying and local snapshots, so nothing is skipped. It is a good habit before installing macOS updates, moving large libraries, or deleting files you might want back. stopbackup cancels a run cleanly; the next scheduled or manual run resumes where it left off.

03Risk

RiskLow risk

RequirementsA configured Time Machine destination must exist.

04Undo

Undo

$ tmutil stopbackup

05Sources

tmutil — Time Machine utility (macOS man page)
SS64 · technical · 2026-09-17
Evidence: Documents startbackup (with optional --rotation flags) and stopbackup to abort an in-progress backup.

Last verified: 2026-09-18 · Category: System & Settings

06Related solutions

List Local Time Machine Snapshots with tmutil

macOSbackupstoragetmutil

See every local APFS Time Machine snapshot on your startup disk and delete ones you no longer need.

Low risk ✓ 2026-09-17

Clone Folders with Full macOS Metadata Using ditto

macOSbackupcopyresource-fork

The copy command that keeps Finder flags, ACLs, resource forks, and exact permissions intact.

Medium risk ✓ 2026-09-17

Export and Import Preference Domains with defaults

macOSplistbackupdefaults

Snapshot an entire app's settings to a plist file, then restore or migrate it later.

Low risk ✓ 2026-09-17