macOS · Storage & Backup
Back Up Your Mac with Time Machine
Time Machine automatically backs up your entire Mac — apps, accounts, preferences, and files — to an external or network drive, so you can restore individual files or your whole system if something goes wrong.
How to open Time Machine Backup
- Connect an external drive or set up a network backup destination.
- Open System Settings → General → Time Machine.
- Click 'Add Backup Disk' and select your drive.
- Turn on 'Back Up Automatically' for continuous protection.
What you should know
- Time Machine keeps hourly backups for the past 24 hours, daily backups for the past month, and weekly backups older than that.
- You can browse and restore previous versions of a file directly from Finder.
- A dedicated external drive is recommended and can be encrypted for extra security.
- Time Machine can also back up to a supported network-attached storage device.
Time Machine only protects files while the backup drive is connected — keep it plugged in regularly, or use a network backup location for automatic coverage.
Why it matters
A backup is the only real defense against drive failure, ransomware, accidental deletion, or a spilled coffee — without one, losing your Mac means losing everything on it. Time Machine's versioned backups also let you recover an earlier draft of a document or undo a mistake from days or weeks ago, not just restore after total loss. It's especially critical to have a current backup before any major software update or hardware repair.
Best practices
- Dedicate an external drive solely to Time Machine rather than sharing it with other files.
- Encrypt the backup drive so your backed-up data gets the same protection FileVault gives your internal disk.
- Keep the backup drive connected on a regular schedule (daily is ideal) rather than only occasionally.
- Periodically test a restore of a single file to confirm the backup is actually working.
- Add a second, off-site backup (like a cloud service) in addition to Time Machine as protection against theft or fire.
Common problems and fixes
- Time Machine reports the backup disk is full.
- Time Machine automatically deletes its oldest backups to make room; if it can't keep up, use a larger drive or exclude large folders you don't need backed up.
- Backups are taking a very long time or seem stuck.
- The first backup can take hours depending on data size; later backups are incremental and much faster — check the Time Machine menu bar icon for live progress.
- 'Time Machine could not complete the backup' error keeps appearing.
- Verify the drive is properly connected and not asleep, run Disk Utility's First Aid on the backup disk, or reformat and start a fresh backup if corruption persists.
Tips and tricks
- Hold Option and click the Time Machine menu bar icon to reveal a hidden 'Browse Other Backup Disks' option for checking backups on additional drives.
- Use Migration Assistant with a Time Machine backup to move everything to a brand-new Mac in one step.
- Exclude large, easily re-downloadable folders (like a big Downloads or games folder) in Time Machine's Options to speed up backups and save disk space.
Frequently asked questions
Can I use the same external drive for Time Machine and regular file storage?
It's not recommended — Time Machine works best with a drive dedicated entirely to backups, since it manages the disk space automatically and mixing files can cause confusion or space issues.
How do I restore just one file instead of my whole Mac?
Open Time Machine from the menu bar or Launchpad, navigate to the folder containing the file, and use the timeline on the right to browse back to the version you need.
Does Time Machine back up to iCloud?
No, Time Machine requires a local external drive or a network destination like a NAS — iCloud Drive is a separate, always-on sync service, not a Time Machine backup destination.
Related settings
- FileVault Disk EncryptionFileVault encrypts the entire startup disk on your Mac, so your data stays protected even if the device is lost or stolen. Only someone with your password or recovery key can unlock and read the disk.
- Apple Account & iCloud SynciCloud settings control which of your apps and data — Photos, Mail, Contacts, Find My Mac, and more — stay in sync across all your Apple devices, plus your iCloud storage plan.
- Erase & Reset MacErase All Content and Settings lets you wipe your Mac back to factory defaults — useful for major troubleshooting, or before selling, trading in, or giving away your device.
- Software UpdateSoftware Update in System Settings keeps macOS current with the latest security fixes, features, and app compatibility improvements. Regular updates help keep your Mac fast, stable, and protected.
More Storage & Backup guides for macOS
- Storage ManagementStorage settings show a visual breakdown of exactly what's using space on your Mac's disk, plus built-in recommendations — like storing files in iCloud or automatically emptying the Trash — to free up space without manually hunting for large files yourself.
- Optimize StorageOptimize Storage is a set of Apple-recommended actions — like storing files in iCloud, auto-emptying the Trash, and removing watched TV shows and movies — that free up local disk space with minimal effort. It's found inside About This Mac's Storage settings.
- iCloud DriveiCloud Drive keeps your files in sync across every device signed into the same Apple ID, and can automatically include your Desktop and Documents folders so they're backed up and accessible from any Mac, iPhone, or iPad. Files sync in the background and are accessible from the Finder sidebar or iCloud.com.
- External StorageExternal Storage covers how macOS handles USB, Thunderbolt, and network-attached drives connected to your Mac — formatting them, choosing a file system, ejecting safely, and deciding which ones are eligible for Time Machine backups. Disk Utility is the main tool for managing these drives.
- Documents & Desktop iCloud SyncAutomatically upload the contents of your Desktop and Documents folders to iCloud Drive so they stay backed up and accessible from other signed-in devices.
- Migration AssistantMove apps, files, user accounts, and settings from another Mac, a Time Machine backup, or a Windows PC onto your current Mac using the built-in Migration Assistant utility.