Abstract: A repositioning and retaining device for a mail delivery tray is provided. The device includes a central body to receive at least one mailpiece thereagainst. The central body defines a substantially planar surface. The device also includes at least one intermediate portion operatively connected and arranged substantially perpendicular to the central body. The at least one intermediate portion provides a lateral boundary for the at least one mailpiece. The device further includes at least one peripheral guide extending outward from and in a direction transverse to the central body and operatively connected to the at least one intermediate portion. The at least one peripheral guide engages with a sidewall of the tray to orient and removably secure the device to the tray. A system for repositioning and retaining mail and a method of using the repositioning and retaining device for a mail delivery tray are also provided.