Jimmy Choo, the shoe designer, was asked to make 63 different pairs of shoes for the film, all out of man-made materials (to be animal-friendly along the line of the line of non-animal cruelty, the line of the film). Reese Witherspoon asked to keep them all, along with all of the designer clothing she wore in the film.
Jessica Cauffiel (Margot) and Alanna Ubach (Serena) were originally only going to be in the opening scene, but they were written into the script more, while shooting was going on.
The scenes on the steps of the U.S. Capitol were filmed at the Utah State Capitol. The scenes inside the Capitol were actually filmed at the Illinois State Capitol Building. Both were modeled after and look similar to the national Capitol. Many Salt Lake City and Springfield locals took parts as extras in the movie.
As Reese Witherspoon was growing out her shorter hair from filming Sweet Home Alabama, all Elle's hair and hairstyles throughout the movie are top-grade wigs.
The author of the book "Everything you always wanted to know about how to pass a bill" is shown as Tom Altobello, who is the assistant property master for the movie.
During the opening scene, while looking at the scrapbook, one of the girls points to a photo of Elle with Congresswoman Rudd (Sally Field). She says, "Those are two kick-ass women. I like them, I really like them", a reference to Sally Field's acceptance speech at the 1985 Oscars.
The press junket for the film was held in London instead of Los Angeles because Reese Witherspoon, who was five months pregnant at the time, was shooting Vanity Fair there. MGM flew two-thirds of the junketeers to the city where they stayed at the Grosvenor House, a luxurious prewar hotel.
In the first movie she is said to grad from Harvard as the class of 2004, but in this movie during the intern cheer sequence Margot and Serena introduce them as the class of 2003.