Messages Taking Up Space on a Mac? Clear iMessage Attachments
The Messages app stores every attachment — photos, videos, GIFs — you've ever sent or received, often several gigabytes. Clear them in System Settings → General → Storage → Messages (review and delete large attachments), or by deleting old conversations. Anything kept in iCloud Messages stays available on your other devices.
Why Messages gets so big
Every meme, screenshot and video in your chats is saved to disk. Over years that quietly becomes gigabytes — and none of it shows in Finder. It's one of the sneakier personal space-users, alongside Photos.
Clear attachments and old chats
- Review by size: System Settings → General → Storage → Messages → sort attachments by size and delete the big ones.
- Delete old conversations: right-click a thread → Delete — removes its attachments too.
- Auto-expire: Messages → Settings → General → Keep messages: 30 days / 1 year.
The iCloud caveat
To see Messages' footprint next to everything else on your Mac, MacCleaner's scan lays it all out with real sizes.
Frequently asked questions
Why is Messages using so much storage on my Mac?
It saves every attachment — photos, videos, GIFs — from all your conversations. Over time that's often several gigabytes. Review large attachments in Storage → Messages and delete old chats.
How do I delete iMessage attachments on a Mac?
System Settings → General → Storage → Messages, sort attachments by size, and delete the large ones. Or delete whole conversations to remove their attachments.
Will deleting messages on Mac delete them on iPhone?
If Messages in iCloud is enabled, yes — devices sync. Turn it off first if you want to free space on the Mac only.
Reclaim the space in two taps
MacCleaner scans read-only, shows every file before anything is touched, marks the safe groups, and lets you choose Trash or permanent. Free for up to 500 MB of cleanup a day.
Download for Mac