In June of 2006, Uwe Boll publicly announced a challenge to his numerous critics to "put up or shut up." Based on certain criteria, Boll will select five of his harshest critics to fight in a series of multi-round boxing matches to be held in Vancouver, British Columbia that will be broadcast over the Internet. He planned to use footage from these fights in this movie, but it was soon discovered that they don't fit into the plot of the movie, so the idea was dropped. It’s claimed that they might be part of the DVD when it’s released.
Gary Coleman was offered the chance to reprise his role as one of the central characters from the original Postal 2 (2002) (VG) video game, but turned down the offer because he didn't want to swear.
Uwe Boll only shot 3 to 5 takes of every scene in the movie. He thought that the biggest strength in comedy is the emotion behind the acting, which cannot be kept when trying the scenes too often.
Zack Ward originally auditioned for the role "Officer Greg". But the producers of the movie thought he would fit better into the role of the Postal Dude, so he got that part. The role for Officer Greg went to Chris Spencer instead.
This is the first movie in over 10 years that Uwe Boll actually wrote the script for.
As stated by Uwe Boll on several occasions and in the audio commentary on the DVD, no big agencies wanted their stars in the movie.