- Jim Bolin
- 162.63 cubic metre(s)
- United States (Casey)
The largest mailbox measures 162.63 m³ (5,743.41 ft³) and was created by Jim Bolin (USA) and verified in Casey, Illinois, USA, on 20 October 2015.
There is a hidden stairway located in the post stand and visitors can climb up inside the actual mailbox.