Blog / Sep 19, 2026 · 4 min read
'Other Volumes in Container' Is Huge on My Mac — What Is It?
Open System Settings → General → Storage, click the little reveal arrow, and you’ll see “Other Volumes in Container” sitting there with a number that looks like a typo — especially if you use Time Machine, Docker, or decided to try macOS betas.
It’s not junk you can just delete, and it’s not malware. Let’s demystify it.
What “Other Volumes in Container” actually is
Your APFS container is one big pool of space split into volumes. “Other Volumes in Container” is every volume inside your container that isn’t the system, the user-data volume, or macOS Recovery:
- Preboot and VM volumes — small, but macOS Recovery & sealed-system support volumes
- Time Machine local snapshots — the biggest offender for most people
- Other APFS snapshots — snapshots taken by apps (Carbon Copy Cloner,
tmutil, CloudKit-ish tools) - APFS local snapshots from APFS cloning — files can exist in a snapshot even after you delete them “live”
- The container’s internal snapshot of the system volume — macOS keeps a sealed snapshot to revert upgrades
- Your boot volume’s old snapshots after an upgrade — after a macOS update, the old system version can remain as a snapshot
So the label is really saying: “all the APFS extras in this container.” Some of it is permanent and essential. Most of it isn’t.
Why it’s so large
The usual suspects, in order of size:
- Time Machine local snapshots —
tmutil listlocalsnapshots /. These can take 50–100 GB if a backup drive has been unavailable for a while. macOS keeps them so you can “Time Machine back” before the hourly backup runs. - APFS snapshots by backup apps — CCC snapshots keep prior states of your whole disk.
- Snapshots after macOS upgrades — the system volume is a sealed system, and the multiple snapshots are used to revert/verify, but big cruft can linger.
Check what’s really there:
tmutil listlocalsnapshots /
diskutil apfs list -plist | grep -i -A1 snapshots
diskutil apfs list shows every volume in your container — the white space that isn’t the named volumes is what the Settings UI calls “Other Volumes in Container.”
Safe to delete? Here’s the honest table
| What it is | Can you trim it? | How |
|---|---|---|
| Preboot, VM, Update, Recovery volumes | No — macOS needs them | Leave alone |
| Time Machine local snapshots | Yes (they’re optional) | tmutil deletelocalsnapshots <timestamp> |
| System volume snapshots from upgrades | Yes, old ones | diskutil apfs listSnapshots then prune via Recovery/TMUI tools |
| Other apps’ APFS snapshots | Only if the app allows | Check CCC/TM settings first |
| Free space inside the container | That’s free space showing as used? No — see below | — |
If you just want the quick win, delete old local snapshots:
tmutil listlocalsnapshots /
# for each row that has a timestamp you no longer need:
tmutil deletelocalsnapshots 2026-09-10-083017
Safe to delete? Yes — those are caching copies, not your only backup. Your real Time Machine backups live on your external drive.
The part that’s actually free space (people get this wrong)
The Storage bar under-reports free space. APFS reserves space all over the container, and macOS shows that reserved-but-unused pool as “Other Volumes” rather than as free space — this is one reason the number seems to grow when you haven’t installed anything.
So part of a huge “Other Volumes in Container” is actually space you can use right now. When your user volume needs room, macOS pulls from the container pool. You only need to reclaim space when the container itself is full — which shows up as a disk-full warning, not a scary Settings number.
The tools that actually see it
A standard disk analyzer scans your home folder and shows you files you can delete. The catch: most of “Other Volumes” lives outside your home folder, in volumes and snapshots the Finder hides.
That’s why the practical move is:
- Clear Time Machine local snapshots (biggest, easiest).
- Clean developer caches — DerivedData, Docker, node_modules — which silently grow and make the whole container feel tight.
- Then measure by folder with a tool that shows real byte counts, not a pie chart of named volumes the OS made up.
DiskInsight scans and visualizes the container the way a disk actually stores it — treemap, snapshots-live, top sizes — 100% local, nothing auto-deleted, everything staged to the Trash for review.
Bottom line
“Other Volumes in Container” isn’t junk to nuke; it’s all the other volumes in the APFS container. The useful slice is usually Time Machine local snapshots — check tmutil listlocalsnapshots / first, delete the stale ones, and the Storage number drops by tens of gigabytes immediately.
Then, if the container is still tight, go find the real offender by folder — not by guessing at macOS’s aggregate labels.
Get DiskInsight Pro · $9.99 one-time and see your disk as rows of real gigabytes. Or read the rest of the System Data and Other Volumes explainer for the complete layout.