When Jamie Lee Curtis found out that Lindsay Lohan, who was going to be playing her daughter, had starred in À nous quatre (1998), she asked, "Which twin did she play?", unaware that Lohan had performed both roles.
Producer Andrew Gunn said he initially hoped Jodie Foster, who played the daughter in the original film, Un vendredi dingue, dingue, dingue (1976), would be game to play the mother in the remake. Foster declined, in part because of concerns that the casting stunt would overshadow the movie's overall merit.
The snapshots in the opening credits are actually photos of Jamie Lee Curtis and her daughter Annie Guest.
Kelly Osbourne originally auditioned as Anna (not as Anna's best friend) and was offered the part but decided to back out. Later, she said people told her it was the biggest mistake she'd ever made, due to the success of the movie.
The cover of Tess Coleman's book, "Through the Looking Glass", is the same cover as the original Freaky Friday novel written by Mary Rodgers.
Marc McClure: Annabelle's love interest (Boris) in Disney's original version of Un vendredi dingue, dingue, dingue (1976) as Boris the delivery man.
Dina Lohan: The mother of Lindsay Lohan, Dina is in the end scene when Anna is dancing with Jake. She is in the background dancing with an older gentleman, and looks directly at the camera.