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Deleted files but no space freed on your Mac? The real reasons

Deleting files doesn't free up space on a Mac while the Trash, a Time Machine snapshot, a clone or an app's Recently Deleted still holds them. Here's each fix.

Mac storage basics · Published · 23 min read
Detailed macro shot of hard drive platters and arm mechanism, showcasing intricate engineering.
Photo: Pixabay on Pexels

When deleting files doesn't free up space on your Mac, the files usually haven't gone yet. They're waiting in the Trash, held by a Time Machine local snapshot, sharing their space with a copy you kept, or parked in an app's own Recently Deleted. Less often, an app still has them open, or the figure you're watching hasn't caught up.

None of these is a fault. Each one is macOS keeping a way back for you, or counting space in a way that isn't obvious. Each has its own fix, and most take a minute once you know which one you're facing.

Start with three questions. Is the item still in a Trash, including the Trash on the drive it came from? Do you back up with Time Machine? Did you have another copy of the file on the same disk? Those three explain most cases.

The sections below take every reason in turn: how to recognize it, how to get the space back now, and when it's better to wait.

Why deleting files doesn't free up space on a Mac

Deleting a file removes its name from a folder. The space comes back only when nothing else refers to its data: no Trash, no snapshot, no clone, no second name and no app that still has it open.

That's why the same deletion can free 40 GB on one Mac and nothing on another. What differs is what else was holding on to the file.

Where is the space, usually?

Where the space isThe signWhat to do
The TrashThe Trash in the Dock looks fullLook through it, then empty it
Another drive's TrashYou deleted from an external driveEmpty the Trash with that drive connected
A local snapshotYou use Time Machine; Disk Utility lists snapshotsWait about a day, or remove the snapshots
A clone or hard linkYou'd duplicated the file, or a tool linked itRemove the other copies too, or leave it
An app that has it openA log or working file was in useQuit the app, or restart
An app's Recently DeletedYou deleted in Photos, Messages or MailEmpty it in the app, or wait
A cloud-only fileIt showed a cloud iconNothing: it wasn't using space here
A figure that's lateFinder and Storage settings disagreeCheck Disk Utility, then give it time

Which reason is most likely?

If you've just emptied the Trash and you use Time Machine, the answer is almost always a local snapshot. If you don't use Time Machine, look for a second copy of the file, or an app that keeps its own bin.

If the space comes back after a restart, an app was holding a deleted file open. If it comes back by itself the next day, it was a snapshot, or a figure that took time to update.

What does deleting really do?

macOS's own manual page for deleting a file is clear about it. When a file's last name is removed and no app has it open, all the space it used is freed. If an app has it open, the name goes at once, but the data stays until the app closes the file.

Snapshots and clones work at a lower level still. They share blocks of data on the disk with your files, and a block is free only when nothing at all points to it.

The Trash still has it

Moving an item to the Trash doesn't free its space. Apple puts it plainly: the space doesn't become available until you empty the Trash. Until then, the item sits in a hidden folder, ready to be put back.

How do you empty the Trash?

Click the Trash in the Dock to open it. Look through it first, because emptying is permanent: nothing in Finder brings an item back afterwards. A backup may still have it.

  1. To keep something, select it and choose File › Put Back, or drag it out.
  2. To delete one item for good, Control-click it and choose Delete Immediately, then confirm.
  3. To empty everything, click Empty at the top right of the window, or choose Finder › Empty Trash, then click Empty Trash.

If the Trash refuses to empty, an item may be in use, locked or owned by someone else. Our post on why the Trash won't empty goes through each message and its fix.

Where do files deleted from an external drive go?

Into a hidden Trash on that drive, not on your Mac. Each disk keeps its own, in a hidden folder named .Trashes at its top level, with a separate folder inside for each user.

So deleting 200 GB from an external drive frees nothing on that drive until you empty the Trash while it's connected. Eject it first and the items stay on the drive, out of sight, until you connect it and empty the Trash.

Deleting from an external drive never frees space on your startup disk, either. Before a big cleanup, check which disk is actually short of room.

Does each user on a Mac have their own Trash?

Yes. Your Trash is a hidden folder in your home folder, ~/.Trash, and every other account on the Mac has its own. You can't see or empty theirs from your account.

Storage settings counts other accounts' files under Other Users & Shared. If another account's Trash is full, the person it belongs to needs to log in and empty it.

What about items deleted from iCloud Drive?

Apple says items you move to the Trash from iCloud Drive are removed after 30 days, whatever your Finder settings, and you can empty them sooner. Storage settings doesn't count them in its Trash figure.

Deleting an iCloud Drive item also deletes it from iCloud and from your other devices. If you only wanted it off this Mac, read the section on iCloud below before you empty anything.

Should you let the Trash empty itself?

Finder can erase items that have been in the Trash for 30 days. Choose Finder › Settings, click Advanced, and select Remove items from the Trash after 30 days. Storage settings offers the same switch as Empty Trash automatically.

It stops the Trash from becoming a second, forgotten store of files. The cost is a deadline: after 30 days an item is gone for good, unless a backup has it.

A Time Machine local snapshot is holding it

If you back up with Time Machine, a deleted file can stay on your disk for up to a day after you empty the Trash. It's the most common reason a large deletion seems to free nothing.

Why does a snapshot keep a file you deleted?

A local snapshot is a frozen view of your startup disk at one moment. It lets you restore a file from an hour ago, even when your backup disk is somewhere else. Anything that existed when the snapshot was taken stays on the disk for as long as the snapshot does.

So a 40 GB video you deleted at 3 pm is still held by the snapshot from 2 pm. Its space comes back when the last snapshot that includes it is removed.

How long do snapshots keep deleted files?

Apple says Time Machine saves a snapshot about every hour and keeps each one for 24 hours. It also keeps a snapshot of your last successful backup until space is needed, and macOS saves one before each update.

In practice, space from a file you deleted today usually comes back within a day. A file that was in your last backup can be held for longer, because that snapshot stays until something needs the room.

How do you know snapshots are the reason?

Open Disk Utility, choose View › Show APFS Snapshots, and select your startup disk's volume in the sidebar. A table at the bottom of the window lists its snapshots, with the date each one was made.

Snapshots with com.apple.TimeMachine and a date in their names are Time Machine's. If some were made after the file existed and before you deleted it, they're very likely holding it.

To add columns such as Private Size and Cumulative Size, click the More menu and choose Show Columns. Snapshots share most of their data with each other and with your files, so no single number says exactly what removing one would free.

How do you get the space back now?

You usually don't need to. Apple says your Mac counts the space snapshots use as available, and Time Machine removes them as they age or when the space is needed.

When something big can't wait, such as a macOS update or a video export, there are two supported ways:

  1. All of Time Machine's local snapshots: choose Apple menu › System Settings, click General, then Time Machine. Click Options, set Backup Frequency to Manually, click Done, wait a few minutes, then set it back.
  2. One snapshot: in Disk Utility's snapshot table, select it, click the Delete Snapshot button and confirm.

Either way, you can no longer restore files from the removed snapshots. Backups on your Time Machine disk aren't affected. The guide to Time Machine local snapshots has more on both.

What changed between macOS versions?

The steps above are the same in macOS 27 Golden Gate and macOS 26 Tahoe, and have been since macOS Ventura. On macOS Monterey and earlier, the setting was in System Preferences › Time Machine: turning off Back Up Automatically for a few minutes did the same job.

What about snapshots from other backup apps?

Backup and cloning apps such as Carbon Copy Cloner can make snapshots of their own, on their own schedule, and some keep them much longer than a day. They hold deleted files in exactly the same way.

Disk Utility lists them next to Time Machine's. Change how long they're kept in the app that made them, rather than deleting them behind its back.

Why can a large copy still fail?

Apple says snapshots don't take the space needed for downloads, copies or installs, because macOS removes them when that space is needed. In practice, macOS doesn't always free it fast enough for the task that asked.

Howard Oakley's tests on macOS Tahoe found copies failing for lack of space while a snapshot still held deleted files. If that happens to you, remove the snapshots yourself, then try again.

Top view of instant old fashioned camera placed on wooden table near torn picture
A local snapshot is a picture of your disk at one moment, and it keeps everything in the picture. Photo: Erik Mclean on Pexels

The space is purgeable, not free yet

"Available" on a Mac isn't the same as "free". Finder's figure includes purgeable space: space macOS says it can free when something needs it. After a large deletion, the gap between the two is often where the missing space is.

What's the difference between free and available?

Apple's Disk Utility guide defines available space as free space plus purgeable space. Purgeable space is space macOS can free by removing files, and you can't remove those files yourself.

Snapshots are a large part of it on many Macs. So are downloaded copies of iCloud Drive files that macOS can remove when Optimize Mac Storage is on, and caches macOS knows it can clear when space is needed.

The guide to purgeable space explains each part, and our post on removing purgeable space says when it's worth doing.

Which number should you watch after deleting?

Where you lookWhat it showsAfter a deletion
Finder's status bar, or Get Info on the diskAvailable: free plus purgeableCan rise while a snapshot still holds the file
Disk Utility's Info windowAvailable, purgeable and freeShows whether the space is really free
Storage settingsUsed and available, by categoryUpdates in the background, sometimes late
Adding up foldersOnly the files you can seeDrops at once, but ignores snapshots

To see Finder's figure, choose View › Show Status Bar in any Finder window. For Disk Utility's, select your startup volume and click the Info button in the toolbar.

Why do Finder and Disk Utility disagree after a deletion?

Because they answer different questions. Finder says how much macOS could make room for. Disk Utility's free figure says how much is unused right now.

Even Disk Utility isn't always consistent. In Oakley's tests, the same snapshot-held space showed as used at one moment and purgeable at another. Treat each figure as a guide, and check the free figure before anything large.

Sometimes you delete a large file, empty the Trash, have no snapshots, and still nothing comes back. If there was another copy of that file on the same disk, the two may have shared the same space all along.

What is an APFS clone?

Apple's file system, APFS, can copy a file without copying its data. Apple's developer documentation describes a clone as a copy that occupies no additional space on disk. Both files point to the same blocks, and only the parts you change later are stored separately.

When you duplicate a file in Finder on the same disk, macOS makes a clone. That's why duplicating a 20 GB video finishes almost instantly.

Why does deleting a duplicate free nothing?

Because the space belongs to both files at once. Delete the copy, and the original still uses every block, so nothing is freed. Delete the original and keep the copy, and the result is the same.

The space comes back only when the last file using those blocks is gone. If you edited one of them, only the changed parts are its own, and deleting it frees just those.

Why does Finder count clones twice?

Finder shows each clone at its full size, and a folder's size counts each one in full. A folder of five clones of a 10 GB file can look like 50 GB while taking little more than 10 GB on the disk.

Finder has no badge or column that says a file is a clone. If a deletion freed far less than Finder said the file took, a clone is a likely reason.

A hard link is a second name for the same file, often in another folder. Delete one name and the file is still there under the other, using the same space. macOS frees it only when the last name is removed.

You rarely make hard links yourself in Finder. Tools do: some backup apps, and some developer tools that share files between projects.

Developer folders that share a cache

Some developer tools fill a project's folder with clones or links of files kept in a shared store. pnpm, a JavaScript package manager, saves each package once and links it into every project that needs it. On macOS it tries cloning first, then hard links.

So deleting a node_modules folder that pnpm made frees little, because the same data stays in pnpm's store. The catalog's entry for the pnpm store says that shared space is freed only when no project uses a package any more.

uv, a Python package manager, clones packages from its cache into each environment by default on macOS. Deleting an environment it made frees only what isn't shared with that cache.

What you deletedShares its space withWhat deleting it frees
A Finder duplicateThe originalOnly the parts that changed
One name of a hard-linked fileIts other namesNothing, until the last name goes
An alias, or an icon in the DockNothing: it only points to the itemAlmost nothing
A pnpm project's node_modulespnpm's storeLittle, until the store is pruned
A uv environmentuv's cacheOnly what isn't in the cache
A file stored only in iCloud DriveNothing on this MacNothing on this Mac

Does deleting an alias free any space?

Almost none. An alias is a small file that points to an item somewhere else. Apple's guide says that when you remove an alias, only the alias is removed; the original item stays on your Mac.

The same goes for an app's icon in the Dock or an item in Finder's sidebar. Removing it leaves the app or folder where it was, using the same space.

A sleek, modern printer situated on a minimalist office desk with a textured background.
A clone looks like a second copy, but both share the same space until one of them changes. Photo: Engin Akyurt on Pexels

An app still has the file open

A file can be deleted while an app is still using it. macOS removes its name at once but keeps its data on the disk until the app lets go. The space reappears when the app closes the file, when it quits, or when the Mac restarts.

When does this happen?

Finder usually stops you: it won't empty the Trash while it knows an item is in use, and says so. The case it can't catch is a file removed by something else while an app keeps writing to it.

A log is the classic example. If a log file is removed while the app that writes it keeps running, the app goes on filling a file nobody can see. Video, audio and virtual machine apps can hold large working files open in the same way.

How do you free the space?

  1. Quit the app you suspect, and any helper it left running in the menu bar.
  2. If you don't know which app it is, restart your Mac. Every app closes its files, and the space comes back.
  3. Check Disk Utility's free figure afterwards, to confirm it did.

A restart also clears macOS's swap files, so free space can jump for a second reason. That's normal. Swap grows again as you use apps that need a lot of memory.

Why does some space fill up again straight away?

Caches, logs and temporary files belong to apps that make them again as they run. Deleting them frees space for a while, then the apps write them again.

If a folder you cleared fills up again within days, the app is doing its job. Clearing caches frees space; it doesn't make a Mac faster, and doing it on a schedule mostly costs your apps time rebuilding.

The file was in iCloud Drive or another cloud folder

Files in iCloud Drive may or may not be on your Mac. Some show a cloud icon: they're stored only in iCloud and take no space here. Deleting one of those frees iCloud storage, but nothing on your Mac.

Was the file only in iCloud?

With Optimize Mac Storage on for iCloud Drive, macOS keeps older files only in iCloud when space is needed, and downloads them when you open them. Apple says that if space isn't needed, everything stays on the Mac.

The same applies to your Desktop and Documents folders if Desktop & Documents Folders is on. A file there can show its name and icon while its contents are in iCloud.

Remove Download or Delete?

To free space on this Mac and keep the file, Control-click it in Finder and choose Remove Download. The file stays in iCloud and on your other devices, and downloads again when you open it.

Delete is a different thing: it removes the file everywhere. It's an easy way to lose files while trying to free space, and it isn't even faster, because the deleted item waits in the Trash.

To keep a file on this Mac whatever Optimize Mac Storage decides, Control-click it and choose Keep Downloaded.

What about Dropbox, OneDrive and Google Drive?

They work on the same idea under their own names. Files you've opened or made available offline take space on your Mac; online-only files don't, so deleting them frees nothing here.

To free local space, use each app's own command in Finder: Make online-only in Dropbox, Free up space in OneDrive, and turning off Available offline in Google Drive. Deleting a file in the synced folder deletes it from the service too.

Photos, Messages and Mail keep their own bins

Apple's apps hold on to deleted items for a while, so you can change your mind. Deleting in the app moves things to its own Recently Deleted or Trash mailbox, not to Finder's Trash, so emptying Finder's Trash does nothing for them.

Photos keeps deleted items for 30 days

Deleted photos and videos go to Recently Deleted, below Utilities in the Photos sidebar, and stay there for 30 days. They keep their space until then.

To free it now, open Recently Deleted, select items and click Delete with the number of items, or click Delete All. If the album is locked, click View Album and unlock it first. After that, Photos can't recover them.

Apple says that with iCloud Photos on, photos and videos you delete on one device are deleted everywhere you use iCloud Photos.

Did you delete the original after importing it?

Photos normally copies what you import into its library. Deleting the original from Downloads or a camera card frees that copy's space, but the photo still takes space inside the library.

It works the other way too. Deleting a photo in Photos doesn't touch a copy you kept in a folder, and that copy keeps its own space.

Messages has Recently Deleted too

Deleted messages and conversations go to Recently Deleted for up to 30 days. To clear it now, choose View › Recently Deleted, select the conversations, click Delete, and follow the steps on screen.

Attachments go with the messages they belong to. With Messages in iCloud on, deleting on your Mac deletes on your other devices too.

Mail keeps a Trash mailbox

Deleted emails go to the Trash mailbox until they're erased. Choose Mailbox › Erase Deleted Items and pick an account, or Control-click a Trash mailbox in the sidebar and choose Erase Deleted Items.

To choose when Mail erases them by itself, choose Mail › Settings, click Accounts, select an account, click Mailbox Behaviors, and use the Erase deleted messages menu.

AppWhere deleted items waitHow longTo free the space now
FinderThe TrashUntil emptied, or 30 days if setFinder › Empty Trash
Finder, for iCloud Drive itemsThe Trash30 daysEmpty the Trash
PhotosRecently Deleted30 daysDelete All in Recently Deleted
MessagesRecently DeletedUp to 30 daysView › Recently Deleted, then Delete
MailThe Trash mailboxAs set in Mailbox BehaviorsMailbox › Erase Deleted Items
How long deleted items keep their space, by default
  • Time Machine hourly snapshot1 days
  • iCloud Drive items in the Trash30 days
  • Photos: Recently Deleted30 days
  • Messages: Recently Deleted30 days
  • Trash, with automatic emptying on30 days

From Apple's documentation for macOS 27. Finder's Trash keeps everything else until you empty it, and Time Machine keeps the snapshot of your last backup until space is needed, so neither has a fixed end.

Space held inside another file

Some apps keep all their data inside one large file or package. Deleting things inside it doesn't always shrink it on your Mac straight away, and sometimes doesn't shrink it at all until you ask.

Why doesn't Docker give the space back?

Docker Desktop keeps every image, container and volume inside one disk image file, Docker.raw. Delete images or containers in Docker Desktop, and Docker gives the space back to your Mac by itself, sometimes after a few minutes.

Deleting files inside a running container usually gives nothing back to your Mac. The guide to Docker.raw says what to remove, and why never to delete the file itself.

Why doesn't a virtual machine shrink?

A virtual machine's disk is a file on your Mac that grows as the guest system writes to it. Deleting files inside the guest frees space there, but the file on your Mac can stay the same size until the app reclaims the space.

Parallels Desktop, for example, has Free Up Disk Space in its File menu, with a Reclaim option for the selected machine, and a setting to reclaim space when a machine shuts down. Other apps have their own tools; check their documentation.

Libraries that Apple's apps manage

The Photos and Music libraries are packages with a database inside. Removing items in the app frees their space. Removing files inside the package in Finder can damage the library.

Make changes to them only in the app that owns them.

When the number just hasn't caught up

Sometimes the space really is free, and the figure you're watching is late. Storage settings is the usual one.

Why does Storage settings still show the old figure?

Storage settings works out its categories in the background. Apple says its figures update automatically as you free up space, but not how quickly, and after a large change it can take a while.

Don't delete more to make it move. Check Disk Utility's free figure instead, which reflects the disk as it is now.

Does a restart help?

Often. It ends any app that was holding a deleted file open, and it clears swap files. If space you're sure you freed hasn't appeared after a restart and a day, look at snapshots and copies again.

A worked example

Say your Mac shows 30 GB available, and a video project needs 60 GB. You find a 45 GB folder of old screen recordings and move it to the Trash. Nothing changes.

  1. You empty the Trash. Finder's available figure may rise, but Disk Utility's free figure hardly moves, and the export still stops for lack of space.
  2. Disk Utility lists Time Machine snapshots made in the last few hours, while the recordings still existed.
  3. You set Backup Frequency to Manually, wait a few minutes, and set it back. Disk Utility's free figure rises by roughly 45 GB, and the export runs.

If some of those recordings had been Finder duplicates of files you kept, that part would still be in use. If they'd been on an external drive, you'd have needed to empty the Trash with the drive connected, and your startup disk wouldn't have gained anything.

Mistakes that make it worse

Most of these come from wanting the number to move right now. Find the reason first; the fix is usually one step.

Should you delete more until the space shows up?

No. If a snapshot is holding the space, deleting more only adds to what it holds, and you lose the chance to restore those files. If a clone is the reason, deleting other files doesn't help at all.

Should you delete iCloud files to free local space?

No. Deleting an iCloud Drive file deletes it from iCloud and every device, and frees nothing on your Mac until the Trash is emptied. Remove Download frees the space and keeps the file.

Is it safe to empty every bin at once?

Only after you've looked. The Trash, Recently Deleted and Mail's Trash mailbox are your last chance to change your mind, and emptying them is permanent. After a big cleanup, look through each one first.

Should you paste a Terminal command to force the space back?

No. Guides that tell you to paste a command to delete snapshots or "purge" space are common. Commands that delete can't be undone, and fake cleanup guides are a known way to install malware. Everything in this post works in Finder, System Settings, Disk Utility and the apps themselves.

Will reinstalling macOS bring the space back?

It's the wrong tool. Space held by snapshots, clones, open files or an app's bin needs one of the fixes above, not a reinstall. Reinstalling costs hours, and erasing the disk costs your data if a backup isn't complete.

Close-up of an eerie doll half-buried in a cardboard box, evoking mystery and curiosity.
Photos, Messages and Mail each keep a bin of their own, and Finder's Trash can't empty them. Photo: ClickerHappy on Pexels

How the app does it

Wombit shows what's using your storage, explains each item in plain language, and clears it safely: Trash first, undoable and logged. File names and paths never leave your Mac.

Its space meter shows the available space beside a bar that ends in what's truly free. The Why the numbers differ panel next to it says how much of the gap is purgeable and how many local snapshots there are, so you can tell when a snapshot is holding space you thought you'd freed.

Its scan counts hard links and fully shared APFS clones once, the way macOS counts space, so a folder of duplicates isn't counted twice. Folders macOS didn't let it read are listed, not skipped.

The places this post is about each have a catalog entry and a level:

  • ~/.Trash

    Trash

    Items you've moved to the Trash. They still use space until the Trash is emptied.

    Review first · Explained only: the app shows you how

  • Time Machine local snapshots

    Hourly snapshots of your startup disk that Time Machine keeps on the disk itself, so you can restore files even without your backup disk.

    Managed by macOS · Runs tmutil for Time Machine's own snapshots, through the helper

  • ~/Library/Mobile Documents

    iCloud Drive

    The iCloud Drive files that are downloaded to this Mac, including the iCloud folders that apps use.

    Usually safe · Explained only: the app shows you how

  • ~/**/*.photoslibrary

    Photos library

    A Photos library: your photos and videos, your edits and albums, and the previews Photos makes from them.

    Managed by macOS · Explained only: the app shows you how

  • The Trash is Review first: it may hold the only copy of something. The app empties it only when you ask, after a confirmation that says how many items it will erase, how much space they take and that you can't undo it. It empties only your own Trash.
  • Local snapshots and the Photos library are Managed by macOS: explained, handled through macOS's own mechanism, never moved. The Local Snapshots page lists every snapshot, when it was made and which app made it.
  • iCloud Drive is Usually safe: the app never removes its files, and its entry explains Remove Download instead.

When you choose, the app removes Time Machine's own snapshots with Time Machine's tool, with an administrator's name and password. Because macOS doesn't say what a snapshot holds, it measures the available space before and after, and shows the difference.

The space meter, the explanations, Undo, Put Back and Empty Trash are free. Cleanup and removing Time Machine snapshots are PRO: one payment of $4.99 with lifetime access. Every Pro tool's review is free to open, so you see what would go and why before you buy.

Frequently asked questions

Why is my Mac storage not going down after I delete files?

Usually because the files are still somewhere: in the Trash, in a Time Machine local snapshot, in a copy that shared their space, or in an app's own Recently Deleted. Empty the Trash first. If you use Time Machine, check Disk Utility for snapshots made while the files still existed.

How long does it take for space to come back after emptying the Trash?

Without Time Machine, it comes back right away, though Storage settings can take a while to show it. With Time Machine, hourly local snapshots can hold deleted files for up to 24 hours, and the snapshot of your last backup until space is needed. You can remove the snapshots sooner in Time Machine's settings or Disk Utility.

Why is my external drive still full after I deleted files from it?

Files you delete from an external drive go to a hidden Trash folder on that drive. They keep their space until you empty the Trash while the drive is connected. Deleting files from an external drive never frees space on your Mac's startup disk.

Does deleting a duplicate file free up space on a Mac?

Often it doesn't. When you duplicate a file in Finder on the same disk, APFS makes a clone that shares the original's space, so deleting either one frees nothing while the other remains. Only the parts you changed after duplicating belong to one file alone.

Does deleting photos in the Photos app free up space?

Not straight away. Deleted photos and videos stay in Recently Deleted for 30 days and keep their space until then. Open Recently Deleted below Utilities in the sidebar and delete them there to free the space now. With iCloud Photos on, they're deleted on your other devices too.

Why does Finder show more free space than Disk Utility after I delete files?

Finder shows available space, which includes purgeable space that macOS says it can free when needed, such as local snapshots. Disk Utility can show free space on its own. After a deletion, the difference is often a snapshot that still holds what you deleted.

Will restarting my Mac free up space?

It can. A restart closes every app, so files that were deleted while an app still had them open finally release their space, and it clears swap files. It doesn't remove Time Machine snapshots or empty any Trash.

Sources

  1. Free up storage space on Mac · Apple
  2. About Time Machine local snapshots · Apple
  3. Delete files and folders on Mac · Apple
  4. Get detailed information about a disk in Disk Utility on Mac · Apple
  5. About Apple File System · Apple Developer
  6. Aren't snapshots purgeable? · The Eclectic Light Company