Tom Hanks' wife, Rita Wilson, saw the play and recommended that her husband produce a movie version. In an interview with the German magazine "Cinema," Nia Vardalos mentioned that she hung up when Hanks called because she did not believe it was really him.
According to Nia Vardalos, paying for catering during the film proved not to be a problem. Wherever the film was being shot, whenever local Greek restaurants learned about it, they sent over lots of free food.
Nia Vardalos's real-life husband at the time of the filming, Ian Gomez, plays Ian's best friend, Mike. The couple divorced in 2018.
My Big Fat Greek Wedding is the highest-grossing romantic comedy film of all time.
The scene where Andrea Martin playfully grabs John Corbett's hair was ad-libbed. Martin had forgotten her lines, played with Corbett's hair (to which Corbett stayed in character and played along), remembered her lines and continued. Nia Vardalos said it worked out so well, they decided to print the take and use it.