Herman Post is Jon Arbuckle's mailman.
Garfield constantly torments Herman by ripping off his pants, leaving him shredded and scratched and playing practical jokes on him. Herman perpetually tries to find a way to deliver the mail safely, rarely succeeding. Garfield enjoys tormenting Herman because he does not think dogs should have all the fun.
Herman is the mailman for Jon's neighborhood because no one else will put up with Garfield's tricks. In The Garfield Show, he takes advantage of this predicament by taking a two week vacation every year, getting a raise when returning early.
Herman has oversized cheeks and brown/yellow/white/gray hair, which includes a mustache. He wears a blue hat and outfit.
Herman is dedicated to his job as a mailman, although Garfield's constant attacks have often taken a physical and mental toll on his well-being.
- He succeeds in delivering the mail safely by folding the mail into paper airplanes and throwing them at the house, to which Garfield replied, "NO FAIR!".
- Possibly non-canon, the mailman succeeded in a splash screen, which had him in a gi and a black belt and Garfield in a defeated position.
- He succeeded by wearing a suit of armor.
- He brought his assistant, an enormous man named Waldo, who then jumped on Garfield.
- He brought Fido, a snake.
- Garfield tries to steal Herman's letters as the Caped Avenger (one of his alternate forms) on March 30, 1979 and fails.
- On multiple occasions, he brought his big dog against Garfield.
- He once dumped the mail in the mailbox, but while running away, he ran out onto the street and got hit by a car.
- He once told Jon about a box with a cat inside (Nermal) with insufficient postage and a destination in Abu Dhabi. Jon then immediately suspected it was Garfield's doing.
- Garfield once tried to jump off the roof with a bungee cord while wearing a spider costume. Herman moved just after Garfield pounced, causing Garfield to crash into the ground.
- He disguised himself as a large dog and put the mail in the mailbox. Garfield became suspicious and proceeded to chase him.
- Garfield once hid in the bushes with a large, spiked club in wait for the mailman, unaware that Herman had already delivered the mail.
- He wore chain mail socks.
- Garfield once flown into the house, noting after impact "did you know the mailman has been working out?"
- Garfield once hit Herman with a splut pie, yanked down his pants, and stole his bag of mail, but Herman had hid the mail in his jacket. The mailbag that Garfield had then began to tick like a bomb.
- In "The Mysterious Machine", he got a big tank which allowed him to deliver the mail safely, but later got rid of it as he thought Garfield's machine would rip the top off and throw him in the mud.
- In "Surprise Package" from Garfield's Scary Tales, he announces his retirement to Garfield and gives him a package as a peace offering, which contains a giant ugly spider the size of a basketball. After Garfield squishes the arachnid from passing out in fright, Herman is last seen leaving the area in an ominous silhouette.
- "The Big Sneeze"
- "Cyber Mailman"
- "Land of Hold"
- "Dog Days"
- "Garfield Astray"
- "Cuter Than Cute"
- "A Gripping Tale"
- "Full of Beans"
- "Rain or Shine"
- "Parrot Blues"
- "Furry Tales"
- "Land of Later"
- "The Superhero Apprentice"
- "What a Difference a Pet Makes"
- "Partners in Mime"
- "Online Arbuckle"
- "Muscle Mouse"
- "The Mysterious Machine"
- "Little Trouble in Big China"
- "Bewitched: Bewitched & Bewildered" (cameo)
- "The Mean Machine"
- "Glitter Gulch"
- "Against All Tides"
- "Lasagna Tree"
- "For Mice"
- "Silence of the Sheep"
- "Home Sweet Home"
- "Delicious Donut Day"
- "My Dog, the Cat"
- "Fraidy Cat"
- "Very Very Long Night"
- In Garfield and Friends, Herman's hair and mustache are light brown. In The Garfield Show, they are yellow. In the comic strip and other media, his hair and mustache are shown to be either white or gray.
- In "Delicious Donut Day", Herman reveals that he shares a birthday with Jon Arbuckle.