Delete messages and conversations in Messages on Mac
Messages saves your conversations automatically, so even if you turn off your Mac or start using another device, you can pick up where you left off. However, you can delete messages and entire conversations.
Set how long to keep messages
In the Messages app on your Mac, choose Messages > Settings, then click General.
Click the “Keep messages” pop-up menu, then choose an option.
Important: If you choose an option other than Forever, your conversations (including all attachments) are automatically removed after the specified time period elapses.
You can also set this option in iCloud settings. See Change iCloud settings.
Delete one or more messages
In the Messages app on your Mac, select a conversation.
Note: When you delete a message, it’s moved to the Recently Deleted folder on your device, but not anyone else’s. When you want to delete a message for everyone, use Undo Send.
Delete a conversation
In the Messages app on your Mac, search for a conversation.
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 .
Tip: You can also delete several conversations at the same time. Select the conversations in the sidebar, Control-click, then choose Delete.
Recover a recently deleted message or conversation
When you delete a message or conversation, it’s moved to the Recently Deleted folder. You can view and recover items in the Recently Deleted folder for up to 30 days. After 30 days, the messages are removed from all your devices. After 40 days, the messages are permanently deleted from iCloud.
In the Messages app on your Mac, choose View > Recently Deleted.
If you don’t see Recently Deleted, you may not have deleted a conversation within the last 30 days.
Select the conversation in the sidebar.
Do one of the following:
Recover a recently deleted message or conversation: Click Recover.
Permanently delete a recently deleted message or conversation: Click Delete.
If you use Messages in iCloud, deleting a message or conversation on your Mac deletes it from all your devices where Messages in iCloud is on. See Set up iCloud for Messages on all your devices.