Continuity: In the scene where Andie and Ben are riding the motorcycle and she is wearing a white tank top, you can see the outline of her bra. When they go back to his parents' house and Ben takes off Andie's tank top in the bathroom, she doesn't have a bra on.

Continuity: In the scene where Ben just ran down the fire escape to Andie, she walks away waving. In the shot of her front side she's waving with her right hand, and then in the next shot (a rear shot) she has her left hand up.

Continuity: When the guys are looking at Andie's purse on Ben's desk, the two handles are sticking straight up but the close up shot shows the front handle folded over, and then the next wide shot shows them both up again.

Continuity: When Andie brings the dog into Ben's office, Ben, Thayer and Tony are standing around listening to Ben complain about how Andie is driving him crazy. Tony is holding a white mug with black writing on it, and he hands Ben a plain black mug. Just as Andie walks in, the shot changes to her, then back to Ben and his friends. However, now Ben has a gray colored mug and Tony has a black one.

Continuity: NBA Finals-Game 1. Andie wants Ben to buy her a Coke. During this scene, the camera cuts back and forth between Andie and Ben, and the basketball game. When Ben first looks at the game clock there is a little over a minute left in the game. He rushes to get her soda, and when he gets back, she says she wanted Diet Coke. There is a shot in this sequence where the camera is filming the basketball action, and you can see the game clock with over 7 minutes remaining, even though they are supposed to be nearing the 30 second mark.

Factual error: In the very first scene in the film when the magazine covers are flashing up, the very first one has a headline which says "loose that belly". For a film whose title has the word "lose" in it, you'd think that they could spell this properly.

Visible crew/equipment: In the scene when Ben and Andie are having the couple's counselling session, in the reflection of the consellor's glasses, you can see the filming crew.

Continuity: In the scene where Andie is trying to get Ben to look at the photo album and Andie starts to cry, Ben covers his mouth with his fist. In Andie's close up, you can see that Ben has his hand beside his beer bottle. When it shows a close up of Ben again, his fist is still on his mouth.

Continuity: Towards the end of the movie when Michelle and Andie are watching the Final Game at Michelle's apartment, the doorbell rings. Michelle assumes it is the Chinese food they have ordered. As she walks to the door she picks up her wallet. When she answers the door and realizes it is not Chinese food but Mike, she slams the door and puts her wallet back down on the table. Before she re-opens the door to talk to Mike she has her wallet back in her hand and puts it back on the table, again.

Continuity: In the scene where Ben is changing his shirt in his office, and the women outside are watching him, when he puts a new shirt on, the left side of the collar is tucked into the inside of the shirt. The camera cuts to a side angle, and the collar has mysteriously corrected itself.

Continuity: Ben has to pick a shirt so he says, "Stripes," and in the shot facing Thayer, he throws the stripe shirt with his left hand, yet in the next close-up facing Ben, Thayer is tossing the shirt with his right hand.

Continuity: At his office, when Ben starts removing his tee shirt, three women, holding their coffee mugs, are huddled together glaring at him in two shots. After he flicks the ad with his fingers, two of those women are walking around at the other end of the office, doing their work. Yet when Ben says, "No way!" he turns and sees the three women, still huddled together holding their coffee mugs, glaring at his body.

Continuity: When the truck hits the pot hole and splashes Ben and Andie with water, Ben's shirt changes from being semi wet to almost totally wet when the camera angle changes.

Continuity: In the scene where Ben and Andie are in the bathroom together, after they have been splashed by the truck outside, Ben's shirt is almost dry and only a faint line of wetness is visible. In the next shot of them in the bathroom, his shirt looks as if has been just drenched a few seconds before.

Continuity: During the Knicks game, there is a shot of the scoreboard with about one minute left. The main score says that the Knicks have 93 points. However, if one adds up the player-point totals on the left (42, 9, 21, 14, 8), the Knicks supposedly have 94 points.

Continuity: When Ben and Andie are visiting Ben's parents, Ben takes the baby to change his diaper. When he comes back, the baby has a blanket wrapped around him, but when Ben passes the baby to his father, the blanket is not there any more.

Continuity: When Andie walks in and surprises Ben at work, Ben shouts, "Andie!" and he places his light mug down and then it is seen next to the side pocket on the pool table. In the close-up of the dog on the pool table, the light mug is closer to the corner pocket, with the black mug.

Continuity: When Andie and Ben leave the first game of the NBA finals and Andie is climbing into the cab, she is holding the cup of Diet Coke. In the next shot Ben is holding the cup. Then in the next shot Andie is holding the cup yet again and in the other hand.

Continuity: When Ben walks into his office, just before he says, "What's up kitty cat?" in this shot in the background the woman with a black sleeveless top is leaning over a desk speaking with someone. In the next shot as Ben asks, "Where were you man?" that woman is standing by the coffee machine at the wall at the right. Yet, in the next shot, she's back where she was in the first shot.

Continuity: When Kate Hudson is eating the hamburger, she takes one big bite. And in the few shots after that it can be seen that one perfect bite has been taken out of the burger. In the last shot you see of the burger from behind Kate Hudson nearly 1/4 of the burger has been eaten.