Short answer: delete message attachments on iPhone by reviewing the heaviest conversation media first. The goal is to remove old videos, screenshots, voice notes, and image-heavy threads that still take space, not to wipe out useful conversations blindly.
Message attachments become a separate storage problem because they live outside the simple “camera roll cleanup” mindset. People often clear photos and still wonder why the phone feels full. One answer is that Messages can still be holding large attachments the earlier cleanup never touched.
What to do first
Review the largest message threads and attachment-heavy conversations before smaller chats.
Start with old videos, duplicate sends, screenshots, and low-value reference images.
Keep active conversations intact if the real problem is attachment weight rather than the message history itself.
After the Messages pass, review whether those same images or videos were also saved into Photos.
Why message attachments keep storage full
Heavy videos and screenshots often get sent, saved, and forgotten.
The same media can exist in both Messages and Photos.
Old conversations may still hold large files even when you never open them anymore.
Message storage is easy to overlook because it does not feel like part of normal photo cleanup.
Why third-party apps cannot clean iMessage for you
iOS keeps Messages inside a protected sandbox that third-party cleaner apps cannot scan directly.
If an app implies it can review or bulk-delete your iMessage attachments for you, treat that claim carefully.
The practical cleanup route for Messages is native iPhone storage surfaces, not external message-cleaner automation.
Use the native Messages storage view
Open Settings, then General, then iPhone Storage, then Messages.
Review Videos, Photos, GIFs and Stickers, or Top Conversations instead of scrolling years of chats manually.
Start with the heaviest attachments there, then come back to individual threads only if something still needs selective review.
Where Cleanor helps after the Messages pass
If the same media also lives in Photos, the next win usually comes from grouped photo-library review. Cleanor for iPhone is useful once message clutter turns into normal duplicate photos, screenshots, similar shots, and heavy videos in the library.
What people usually ask next
Should I delete whole chats? Only if the conversation itself no longer matters. Often the smarter move is removing heavy attachments first.
Why is storage still full after deleting photos? Because Messages, downloads, and app media may still be taking room.
What should I clean after Messages? Saved screenshots, duplicate videos, and old photo-library clutter are usually the next passes.
If your phone still feels full after cleaning Messages, continue to Why iPhone storage stays full after deleting photos. If the issue has moved into Photos, open How to free up iPhone space.
Message cleanup works best when you remove attachment weight first and only delete whole conversations when they truly no longer matter.