Permanently delete Mac mail messages?

That depends on what type of account you have. For IMAP or Exchange accounts, it should be immediate. These accounts sync your client with the server, so if something is deleted from the trash locally it should be also on the server.

If you still have a POP account, it depends on the settings. It may be set to delete immediately after downloading, or after a set amount of time. The trash in your mac is not connected or synced to the trash on the server.

Press Command-, or choose Mail->Preferences.

This opens the Mail Preferences; then click Accounts.

Each account will say what type it is:

UteHwk wrote:

Also, is my email stored on a server in the cloud?

Again, it depends...

For POP accounts, mail is downloaded and stored in your Mac.

For IMAP and Exchange accounts, mail is synchronized between devices.

This makes it easy to access your e-mail in your Mac as well as the iPhone, for example.

You can, however, make sure to keep messages only on your mac, independently of the server or other devices: that is what the "On My Mac" location you can see in the Mail Sidebar is for.

Any message that you move or copy to a mailbox "On My Mac" will be stored there, irrespective of the server or other devices.

The Mail application connects with your mail server to get your mail, and sync what you have in your mac with what is in the server.

When you delete an e-mail it typically goes to the Trash folder, and when you delete it from there it should be deleted both in your mac and in the server.

Unless it’s an @icloud.com email account, Apple has nothing to do with your email. Only your email provider can answer the question as to whether copies of it exist anywhere on their servers. I would be surprised if they don’t have backups that are kept for some period of time that might contain email you have since deleted.

I don’t know what Apple’s backup policy is. I’m sure they make backups on a regular schedule to recover from a disaster.

Apple is probably one of the most privacy conscious companies in the world, however, so I wouldn’t be too worried about copies of your emails falling into the wrong hands.

Of course, Apple will cooperate with law enforcement and provide information they are required to under the law when presented with a court order to do so…