Continuity: At the bar/club for the co-worker's engagement party, after Kevin asks Jane if she likes the flowers he sent, Jane excuses herself and goes outside to the back of the bar and starts screaming. When Jane exits she leaves the heavy metal door open so you are able to see inside the club. You also see boxes and other misc. things lying around. Then after Jane hits the wall with her purse, the camera is facing towards her, and you see the scenery change. The door is now a nice wooden door, the misc. scenery is gone and the door is also closed.

Continuity: In the final scene of the movie when Jane gets married on the beach, you see guests arriving and Tess is handing out programs. She hands a program to a blond girl with a brown polka dot dress. In the next scene, we see Tess taking to George and the same woman arrives again and Tess hands her a program again.

Continuity: In the argument in the car in the rain, Kevin has a seatbelt on, but while accusing Jane of being in a creepy love triangle, he has no belt on. When he says "Nice Jane," he has a seat belt on. It is off again when Jane says she is thrilled about the boss and sister marrying. It is on again at the road sign where Kevin doesn't have Spidy vision. When Kevin checks for a cell phone signal once the car stops hydroplaning, the seatbelt is over his collar but when he snaps the cell phone shut, the collar is over the seatbelt suddenly.

Continuity: When Jane is tying George's tie, the part around his collar goes from being seam-side out to in to out again between camera angles.

Continuity: When the sisters are at the baseball game and Katherine Heigl is eating french-fries there is a shot that shows her taking a bite of the french-fry but when the shot changes she has a whole fry in her hand.

Other: When Jane is with George tasting for the wedding menu and Kevin calls and Tess answers the phone she says Jane's phone, then when Kevin and Jane leave together after they run off the road Jane has her phone even though she never went to get it.

Continuity: Kevin and Jane are performing Benny and the Jets on stage. There are two blonds in the crowd, but the one on the right sometimes waves a cell phone or a glass of water, depending on the shot.

Continuity: In the scene where Jane and Kasey are in the yoga class, Kasey goes from not wearing a bra, to wearing a bra.

Continuity: After arriving home depressed from reading the article Kevin wrote in the journal, Jane is seated on her couch beside a pillow. You can see the flower in the lower corner of the pillow, but when Tess is screaming about bridezilla, Jane has moved over and you cannot see the lower flower - but later she has moved for the viewing of the flowers again when Tess leaves.

Continuity: Jane is modeling the yellow dress with red flowers and Kevin has the camera in his right hand but when he says "Oh my God!", his right hand is free to cover his mouth. Then the camera is back in his hand to take the photo. Later when Jane is sitting in the red dress talking with Kevin about things she has done for people as a bridesmaid, her necklace that was off center moves to the center. But when she says "I am Jesus" and then is back off center again.

Continuity: When the friends are at yoga, Jane's hair at the side bangs has fallen out at each side, but then it is all back again in some scenes.

Plot hole: It was said at the end of the movie that all 27 girlfriends wearing Jane's 27 dresses are there with her in Kevin and Jane's wedding. But if you watch carefully, Jane actually helps 28 times (not 27) as a bridesmaid. The last one is the punk-rock wedding where she wears a red and black dress and a spike necklace.

Continuity: When Kevin tries to convince his boss in her office that he wants to do some work using Jane's journal, the pencil in her hair sticks up more sometimes.

Continuity: George and Jane are at the boat house and when they arrive there are no boats in the water behind George. Then a lot appear and from then on there is no continuity of boat positioning in the water. Also during this conversation they are served a meal, but the dish in front of Jane appears unused.

Continuity: Kevin has taken the photo of Jane in the olive green bridesmaid dress but his pointer finger changes position high and low on the camera as he turns it to Jane and back.

Continuity: Kevin and Jane arrive at the bar, and after Kevin announces the pay phone is dead, the bartender sets a glass down and puts his hands on the bar. But after Kevin places the scotch order, there is the sound of a glass being set down again, and a small piece of the serviette shows. After Kevin and Jane dance to Benny and the Jets, Kevin helps Jane off the stage and Kevin admits he cried at the Keller wedding. Some sweat is shown on his neck, but when Jane grabs his neck to kiss him, his neck is dry.

Continuity: At the ballpark, Jane, Tess and George sit down on a concrete bench. A few moments later, when George gets up to play baseball with Pedro, he sets his food down on the concrete bench and you can see that the two women are sitting on a black foam pad that wasn't there before.