When Forrest gets up to talk at the Vietnam rally in Washington, the microphone plug is pulled and you cannot hear him. According to Tom Hanks he said, "Sometimes when people go to Vietnam, they go home to their mommas without any legs. Sometimes they don't go home at all. That's a bad thing. That's all I have to say about that."
When the studio imposed budget cuts, both director Robert Zemeckis and star Tom Hanks waived a large part of their fee in exchange for percentage points, which ultimately netted Hanks in the region of $40 million.
When Forrest first learns to play ping-pong in the infirmary, he is told the trick is to "keep his eye on the ball at all times" by another soldier. After that moment, whenever he is shown playing ping-pong, he never blinks.
With every transition of Forrest's age, one thing remains the same. In the first scene of each transition, he wears a blue plaid shirt.
The line, "My name is Forrest Gump. People call me Forrest Gump," was ad libbed by Tom Hanks while filming the scene, and director Robert Zemeckis liked it so much that he decided to keep it in.
Alexander Zemeckis: The first boy in the school bus who refuses to let Forrest sit next to him is Robert Zemeckis' son.