What is MobileSync Backup, and which iPhone backups can you delete?
- Location
~/Library/ Application Support/ MobileSync/ Backup - Safe to delete?
- Partly, with care Old backups can go. Keep the newest one for any device iCloud doesn't back up.
~/Library/Application Support/MobileSync/Backup is where your Mac keeps the iPhone and iPad backups you make in Finder. Each folder inside is a full device backup, so this is your data. Backups of devices you no longer need can go. Delete them in Finder’s Manage Backups, and keep the newest backup of any device you still use, unless iCloud backs it up.
What is MobileSync Backup?
It’s where your Mac stores local backups of your iPhone, iPad and iPod touch. Apple’s support article points to this exact folder. Since macOS Catalina, Finder makes these backups. Before that, iTunes did, and it used the same folder.
Each backup sits in its own subfolder with a long name made of letters and numbers. The names don’t say which device they belong to, which is one reason Finder’s own tools are the better way in.
A computer backup holds almost everything on the device. Apple lists the Home Screen layout, app data, device settings, contacts and the Camera Roll. If you turned on Encrypt local backup, it also keeps saved passwords, Wi-Fi settings, Health data and call history.
In System Settings, Storage groups these backups with iOS firmware files under a category called iOS Files.
Is it safe to delete?
Not blindly. Nothing in this folder rebuilds itself. There’s no cache mixed in, only backups. Delete the only backup of a phone, lose the phone, and whatever wasn’t in iCloud is gone.
Which backups can go depends on the device:
- A device you sold, traded in or lost. Safe to delete once you’re sure you don’t want anything from it. After that, there’s no way to restore it.
- A device you still use that backs up to iCloud. Usually fine to remove the Mac copy, after you check that iCloud Backup is on and ran recently.
- A device you still use that only backs up to this Mac. Keep its newest backup. That’s your restore point if the device breaks or you replace it.
Always delete a whole backup, never files inside one. Backups are incremental, so files that look old can still belong to the current backup. Apple’s older support guidance, quoted on its community forum, said not to edit, relocate, rename or pull content out of backup files.
Why it gets so big
A backup copies almost everything on the device that isn’t already in iCloud. Apple’s list of exclusions includes iCloud Photos and messages stored in iCloud. So if iCloud Photos is off, the photos and videos in your Camera Roll land in the backup.
It also keeps coming back. When a device is set to back up to your Mac, Finder backs it up again during the next automatic backup. Every device gets its own backup, and old devices’ backups stay until you remove them. If you’ve ever used Archive in Manage Backups, that copy isn’t overwritten by later backups, so it stays as a separate backup next to the current one.
How to clear it yourself
Don’t do this while a backup or sync is running. Then work through these in order.
- Check for a newer backup. On the iPhone or iPad, open Settings, tap your name, tap iCloud, then tap iCloud Backup. If Back Up This iPhone (or iPad) is on, tap your device to see when it last backed up (Apple’s steps). If the device only backs up to your Mac, don’t delete its newest backup.
- Open Manage Backups in Finder. Connect the device with a cable, open Finder and select it in the sidebar. Trust it if asked. On the General tab, click Manage Backups (Apple’s steps).
- Delete what you don’t need. Right-click an old backup, choose Delete, then confirm. The list can include backups of other devices too, so you may be able to clear an old phone’s backup with your current one connected.
- No device to connect? Open System Settings, click General, then Storage. Click the Info button next to iOS Files, select the old backup and click Delete (Apple’s guide).
- Last resort, in Finder. Choose Go > Go to Folder, paste
~/Library/Application Support/MobileSync/Backupand press Return. Switch to list view and look at Date Modified to see roughly when each backup was last updated. Drag only a whole backup folder you’re sure about to the Trash. If you’re not sure, copy it to an external drive first. - Empty the Trash when you’re certain. Dragging to the Trash gives you one last chance to change your mind, which is why we like it. The space comes back only after the Trash is emptied.
Once a backup is deleted or emptied from the Trash, treat it as gone for good unless you copied it to another drive. For more places space hides, see freeing up disk space on Mac.
What SpaceUp Mac does with it
When SpaceUp Mac finds backups in this folder, its Clean tab lists them as one row, “iPhone / iPad backups”, with an orange “Can’t undo” badge. It starts unticked, and the All button never ticks it. The row says removal is permanent and to clear it only if you back up to iCloud or no longer need those devices restored. If you tick it yourself, the app asks you to confirm, naming it and saying it can’t be undone, then clears every backup in the folder at once, directly and not to the Trash (how cleaning works), so to keep one device’s backup and drop another, use Finder’s Manage Backups instead. If Deep Scan can read the MobileSync folder and it’s 80 MB or larger, it shows it labeled “Personal · review carefully” with a note pointing to Manage Backups, and offers Reveal only there, never Move to Trash.
Common questions
Does deleting a backup remove anything from my iPhone?
No. The backup is a copy stored on your Mac, and deleting it leaves the device as it is. What you lose is the ability to restore from that copy.
Can I move backups to an external drive instead?
You can copy a whole backup folder there for safekeeping. To restore from it later, you’d move it back into the Backup folder first. Copy the folder as it is, without renaming anything inside.
How do I stop backups from filling my Mac again?
Select your device in Finder and, on the General tab, choose the option to back up your most important data to iCloud instead of to this Mac. Once iCloud has a recent backup, you can remove the old Mac copy with the steps above.
Is this the same as iOS DeviceSupport?
No. iOS DeviceSupport is Xcode’s cache of debug symbols for devices you’ve plugged in, and Xcode rebuilds it. MobileSync Backup holds real device backups and doesn’t rebuild at all.