Hi Lorraine! You’ve touched on a sore point when it comes to the iOS Mail app, which lacks an obvious way to delete all messages without tapping Edit and then selecting each message one by one.
Personally, I’d love it if you could, say, tap, hold and swipe to select a bunch of messages at once (similar to what you can do in the Photos app), but alas, that doesn’t work in iOS Mail.
There is a way…
That said, there is a way to quickly delete all messages in the inbox of an individual mail account, or in a specific mailbox within an account. But if (like me) you’re a fan of the All Mailboxes view in Mail, the Trash All button is easy to miss.
For some odd reason, the Trash All button doesn’t appear in the All Mailboxes screen. Instead, you’ll need to back up (tap the Mailboxes button with the arrow in the top-left corner of the display) and tap on the inbox of a specific mail account.
Once you’ve arrived at an individual account inbox, tap the Edit button to reveal the Trash All button (it’s in the bottom corner of the screen). Tap it, then tap the confirmation button to delete all the messages in the inbox.
Deleting all messages from a specific mailbox
You can also delete all messages with a specific mailbox within a mail account. Go back to the main Mailboxes screen, tap a mail account under the Accounts heading, tap a mailbox, then tap Edit and Trash All to delete all the messages in the mailbox.
No, the Trash All method isn’t as elegant as being able to swipe to select a bunch of messages at once, but it’s better than nothing.