Continuity mistake: The interior shots of the airliner to Vegas depict a wide-body, two-aisle airliner. However, the aircraft shown during take-off is a Boeing 757, a narrow-body, single-aisle airliner.
Continuity mistake: In the wedding scene, just as the band Wilson Phillips walks in to sing, Annie turns to Helen asking "Really?" with a disappointed look on her face. When the camera zooms out to Wilson Phillips, in the background Annie, Helen and the rest of the bridesmaids are seen to be happily dancing and singing along. Then the shot again zooms into Annie and Helen, where Annie and Helen have just stopped looking at each other, prior to starting to dance and sing along.
Continuity mistake: Melissa McCarthy wears an ace bandage on her left wrist throughout the movie. In the bridal shower scene the bandage is on her right wrist. (01:28:30)
Continuity mistake: When Annie is sitting on the couch at her blind date's house, talking to his kid, her pearl-like necklace usually lays under her coat, but in some shots, they're over the coat or completely hidden.
Continuity mistake: In the scene near the end of the film, when Megan goes round to Annie's house to give her a 'pull- yourself-together' talk, the pendant on Annie's necklace is hanging down onto her chest. But near to the end of the conversation it's disappeared completely and all you can see is the necklace chain. (01:40:00)
Continuity mistake: When everyone except Helen start to show signs of food poisoning in the bridal shop, Becca puts her right hand over her mouth to keep from vomiting. The camera then switches to behind her but her right hand does not appear to be over her mouth anymore. It switches to in front of her again and this time, Becca has her left hand over her mouth.
Continuity mistake: At the bridal shower when Annie loses her temper, Helen is seen with her hand on her chest supposedly in shock. However, in the shot immediately after, her hand is no longer anywhere near her upper body.
Continuity mistake: When Annie is driving on a 2 lane country road between two large fields from the bridal shower, we see Megan drive past her with the car full of puppies. The issue is that Megan was filmed on an entirely different road that has a fence, walkway, double yellow line and is 4 lanes wide - nowhere near what Annie is driving on.
Continuity mistake: When Helen and Annie are in the car and Helen is apologising to Annie, there is a moment where some of Helen's hair gets caught in her left eye due to the wind. In the next shot, it's no longer caught.
Continuity mistake: When Annie and the cop are drinking in the bar, the people behind the cop change from one guy in a dark shirt to a guy in a checkered shirt and a girl.
Continuity mistake: In the scene where Annie and Ted are in bed, she sits up and a pendant is visible lying on her left collar bone. Throughout the scene the pendant switches position several times. (00:53:40 - 00:54:55)
Continuity mistake: When Annie and Helen are taking turns toasting Lillian, Annie goes up for a second time. In the close shot, she is holding the microphone in her left hand and a champagne flute in her right. The camera goes to audience, and when it is back to her, the flute and the mic have switched hands. In the next wide shot, the are back to their original position. (00:26:40)
Continuity mistake: When Annie is pulled over by Rhodes, in one part of the scene a car can be seen coming towards them, but when the angle changes it never passes them.
