How to delete local Messages files and attachments on Mac but NOT on iCloud?

...

Before deleting anything, you'll first want to make sure that you have the messages stored on the device and not in iCloud. You can check that by going to Messages > Settings, click iMessage, and then make sure "Enable Messages in iCloud" is turned off.

This is important to check first, because if you have the messages stored in iCloud, when you start deleting them, they will no longer be visible on any devices that are viewing those iCloud messages.

...

Do I need to turn off "Enable Messages in iCloud" on every device or just the macOS device I want to delete message history from in order to protect my Messages history?

Hello MedInvestor,

Before deleting anything, you'll first want to make sure that you have the messages stored on the device and not in iCloud. You can check that by going to Messages > Settings, click iMessage, and then make sure "Enable Messages in iCloud" is turned off.

This is important to check first, because if you have the messages stored in iCloud, when you start deleting them, they will no longer be visible on any devices that are viewing those iCloud messages.

Once you have confirmed that the messages are stored on the device and not in iCloud, you can proceed with deleting messages.

If you just want to delete specific messages in a thread, use these steps:

1. In the Messages app on your Mac, select a conversation.

2. Select one or more messages (including text messages, photos, videos, files, web links, audio messages, or emoji) in the transcript, press Delete, then click Delete in the dialog.

If you want to delete an entire message thread, use these steps:

1. In the Messages app on your Mac, search for a conversation.

2. Do any of the following to delete a conversation:

• Delete an empty conversation: Move the pointer over an empty conversation, then click the Close button .

• Delete a conversation: Select a conversation, Control-click, then choose Delete. Or, if you have a trackpad or a Magic Mouse, you can also swipe left with two fingers on the conversation in the sidebar, then click the Delete button .

If you accidentally delete something you need, you can recover it from the Recently Deleted folder with these steps:

1. In the Messages app on your Mac, choose View > Recently Deleted.

2. Select the conversation in the sidebar.

3. Do one of the following:

• Recover a recently deleted message or conversation: Click Recover.

Delete messages and conversations in Messages on Mac

Cheers!