Abstract: A mailbox signaling device for rural mailboxes for indicating when the mailbox has been opened to insert delivered mail or retrieve outgoing mail. The device, which is preferably supplied in kit form for do-it-yourself installation, includes a signaling member, preferably including a portion coated with high visibility paint, pivotally secured to the mailbox for swinging movement between raised and lowered positions and a flexible connector extending from the signaling member, through the mailbox interior, to a releasable connection at the door of the mailbox. Opening the door releases the connector allowing the signaling member to fall indicating such door opening.