Much of the scene where Andie crashes Ben's "boy's night" was improvised. Kate Hudson had the idea to toss the platter of veggies at the guys seated at the poker table. Donald Petrie, the director, knew she was going to do this but the actors in the scene were truly surprised.
Andie wears a Harry Winston diamond wreath necklace with an 84-carat yellow diamond pendant (called the "Isadora") attached, valued at approximately $5,280,000 and a pair of 5-carat radiant cut yellow diamond stud earrings worth approximately $125,000.
The dress Andie wears to the Warren Advertising gala was designed around the 84-carat yellow diamond pendant which she wears at the gala. It was designed by fashion designer Dina Bar-El, not the film's costume designer Karen Patch.
When Andie and Ben go to see Sleepless in Seattle (1993), according to the commentary, Kate ad-libbed 2 quotes: "I've always wanted a man like Tom Hanks" and "You can't watch Meg Ryan for 2 hours and not be thinking about another girl."
When Ben is shown the article that Andie wrote, the style and format changes. When the article is first seen, it is completely formatted in blue. When we see it from Ben's point of view, the style changes, with a broken love heart taking up the majority of the page. The font also changes.
The Alexander Hamilton U.S. Customs House, in the financial district of New York City, NY was used for the Astor Museum of Art, where the Warren Advertising Agency hosts a gala in honor of the DeLauers.