Receive an email on your Trello board
Any email sent to your board email address will be created as a new card on your Trello board. If you've configured a custom email address, and have set up forwarding rules, emails sent to that address will also be created as new cards in Trello.
Reply to an email in Trello
To reply to an email that you've received in Trello, open the card and click ‘Reply via Email’ to open the email editor.
Send a new email in Trello
You can also send an email from any existing card in Trello by clicking the SendBoard button and choosing “New Email”.