Continuity mistake: Niles says on Daphne's wedding day that he told her he loved her on his 3 day anniversary, making Daphne's wedding his 4 day anniversary. At Nervosa, Mel says it's their 4 day anniversary, when at this point one more night has passed and it's now 5 days since they married.
Continuity mistake: The butler and Frasier are discussing the new president of the opera board and Ferguson pours Marty a cup of coffee. In the next shot, over Marty's shoulder, we see he already has the cup in his hand, although there was no time for this to happen naturally.
Continuity mistake: Roz is at Frasier's soirée joking with Mr. Worth about selling him some giftwrap. Just before she says "everything but my bracelets", her drink and hat switch from her right hand to her left and her canapé from her left to her right. In the next shot they've switched back again.
Continuity mistake: Roz comes back to the restaurant table, after phoning her babysitter, and says, "I have to go". At this point her purse is over her wrist. As she finishes saying, "Alice got a bead up her nose", she is holding the purse by its strap. A few shots later it is over her wrist again, even though she never moved it.
Continuity mistake: When Niles and Daphne are on the roof having their picnic, Niles tries Daphne's peanut brittle but when she turns away he throws it off the roof, and lays the plate down on the blanket. When Daphne turns back and asks him what happened to the candy, we see him holding the plate again, even though he had no time to pick it up.
Continuity mistake: During the closing credits, when Niles goes to Frasier's with some licorice, Marty is lying on the couch, sick. At first his cane handle is facing the fireplace, but when the shot changes, it has moved about 45 degrees towards the window.When he gets off the couch, the handle is facing the fireplace again.
Continuity mistake: Soon after Abbie has arrived at Frasier's, Daphne says to Niles, "It's cute when you do it," and he has his hand on her shoulder. In the next shot, his hands are in his lap and she is taking a sip from her glass, with no time for a natural change.
Continuity mistake: When Daphne and Niles are on the roof having their picnic, the basket behind them is opened from the center and on the inside on the left are two champagne glasses. A couple of shots later and the glasses are now on the right side, even though no one touched the basket.
Continuity mistake: Frasier is in Donny's office, and Donny is holding a little wedding cake groom. He covers the groom with his hands while he's talking, but when Frasier says, "Daphne realizes you went to great expense," the little bridegroom is visible again, even though in real time it couldn't have happened.
Continuity mistake: At his "reception" Niles has his arm around Mel and says, "I didn't even have to check her teeth" to a member of the horsey set - and the shot then shows Mel and Nils standing apart, even though there was no time for them to have done this.