If your Mac's storage warning keeps appearing despite deleting files elsewhere, Messages is often the hidden culprit. Photos, videos, voice memos, and GIFs exchanged over iMessage accumulate quietly in a dedicated attachments folder, and a few active group chats can push that folder past 10–20 GB without any obvious sign. This guide walks through every reliable method to delete Messages attachments on Mac, so you know exactly what you're removing and what to leave alone.
Why Messages Storage Grows So Fast on Mac
Every image, video, audio clip, document, and sticker you receive in Messages — on your Mac or synced from your iPhone — is stored locally in a Messages container folder. Even if you glance at an attachment for two seconds, macOS saves a full copy. Videos from group chats are the biggest offenders: a single long video can run several hundred megabytes, and a busy family chat can accumulate dozens of them per month.
The container lives at:
~/Library/Messages/Inside, attachments are nested under:
~/Library/Messages/Attachments/This path is not shown in Finder by default because ~/Library is hidden. You must reveal it intentionally before you can inspect or delete its contents.
Step 1 — Check How Much Space Messages Is Using
Before deleting anything, establish a baseline so you know whether the effort is worth it.
- Click the Apple menu () and choose System Settings (macOS 13 Ventura and later) or System Preferences (macOS 12 Monterey).
- Go to General → Storage. macOS will calculate storage categories — this may take a moment.
- Click the Info button (circle-i) next to your drive, then look for the Messages row. If it is not listed separately, it may be folded into "Documents" or "Other".
Alternatively, open Terminal and run:
du -sh ~/Library/Messages/Attachments/This gives you the exact size of just the attachments subfolder. A result above 1 GB is a clear candidate for cleanup.
You can also open Crumb and use its disk visualiser to navigate to ~/Library/Messages/Attachments. Crumb displays the folder's total size and breaks it down by subfolder, which makes it easy to spot whether videos, images, or audio clips dominate — and it surfaces the "Is this safe to delete?" explanation so you understand what you are looking at before touching anything.
Step 2 — Use Manage Storage to Remove Attachments by Conversation
Apple's built-in Manage Storage panel is the safest starting point because it lets you delete attachments per conversation without touching message text or your conversation history.
- Open the Messages app.
- In the menu bar choose Messages → Settings (macOS 13+) or Messages → Preferences (macOS 12).
- Click the General tab and then Manage Storage… — this opens a panel showing each conversation sorted by size.
- Click a conversation to expand it. You will see categories like Photos, Videos, Audio, and Other with sizes next to each.
- Select a category and click Delete, or select the entire conversation row and delete all its attachments at once.
This method is reversible only if the other person re-sends the files. Once you delete, the local copies are gone. Message text and your conversation list remain intact.
Step 3 — Delete Attachments Directly from the Attachments Folder
If Manage Storage is too slow for a large cleanup, you can work directly in Finder.
- In Finder, press Shift + Command + G to open the Go to Folder dialog.
- Type
~/Library/Messages/Attachmentsand press Return. - You will see numbered subfolders. Each corresponds to a conversation hash — there is no human-readable label here, which is why sorting by kind or size is more practical than browsing by name.
- Press Command + A to select all, then press Command + Delete to move everything to the Trash.
- Empty the Trash to reclaim the space.
You can also sort by size first: switch Finder to List view (Command + 2), then click the Size column header. This surfaces the largest attachment bundles so you can be selective rather than deleting everything.
Step 4 — Set Messages to Auto-Expire Old Attachments
macOS can automatically remove messages and their attachments after a set period, preventing the folder from ballooning again.
- Open Messages → Settings → General.
- Under Keep Messages, change the setting from Forever to 1 Year or 30 Days.
- Confirm the prompt — macOS will delete older messages and their attachments immediately.
Choose this setting carefully. If you rely on old conversations for reference, "1 Year" is a reasonable middle ground that keeps recent history while preventing indefinite accumulation.
What Is Safe to Delete — and What to Leave Alone
| Item | Safe to delete? | Notes |
|---|---|---|
~/Library/Messages/Attachments/ |
Yes (with care) | Deletes local copies of received files. Text history is unaffected. |
~/Library/Messages/chat.db |
No | Main message database. Deleting it erases all conversation history. |
~/Library/Messages/chat.db-wal / chat.db-shm |
Only when Messages is closed | Write-ahead log files; safe to remove only after quitting Messages, but rarely necessary. |
| iCloud synced attachments | Yes, carefully | If iMessage is synced to iCloud, the files may still be accessible from iCloud — but this is not guaranteed for all media types. |
Important: Deletion is permanent. Before removing the entire Attachments folder, consider whether any files inside it exist nowhere else. Attachments not saved to Photos or your Downloads folder are not recoverable once the Trash is emptied.
Using Crumb to Verify Before You Delete
If you are uncertain how large the Attachments folder is relative to other hidden Library folders, download Crumb and run a whole-Mac audit. The disk map highlights the Messages container among other large folders, and clicking into it shows a breakdown by subfolder. The AI "safe to delete" explanation is particularly useful here: because the Attachments path looks opaque in Finder, a quick explanation confirming it contains received media — not system data — removes the guesswork before you commit to deleting.
Reclaiming Space After Deletion
After emptying the Trash, run this Terminal command to confirm the folder is clear:
du -sh ~/Library/Messages/Attachments/You should see a much smaller number, or just a few kilobytes if the folder is now empty. macOS should reflect the recovered space in System Settings → Storage within a few minutes, though the bar sometimes takes longer to refresh.
If the number is still high, check whether Messages is still running and whether iCloud is re-downloading attachments. Disabling Messages in iCloud (System Settings → Apple Account → iCloud → Messages) stops new downloads, though it also means older devices will no longer sync message history.
Conclusion
Clearing Messages attachments on Mac is one of the fastest ways to recover several gigabytes without touching your actual files. The built-in Manage Storage panel is the safest route for selective cleanup, while targeting the Attachments folder directly is faster for a full reset. Either way, the key step is checking the folder size first so you know what to expect — and confirming that nothing inside is your only copy before you empty the Trash.