Continuity mistake: When Jake and Elwood are running form the police for the first time, they do a 360 degree spin in the middle of an intersection. The car is spinning clockwise but when the camera focuses on Jake the scenery in the back is spinning as if they were going counter-clockwise. (00:27:35)
Continuity mistake: When the multitude of police are shooting through the door at the end of the film, there are loads of bullets shot at the door, then there are only a couple dozen bullet holes then there is a bunch of bullet holes. (02:12:40)
Continuity mistake: After we've heard why it's so great to be an Illinois Nazi, there's a wide shot of Jake and Elwood's car in a queue, and a policeman walks past the driver's door. In the next shot, the cop hasn't yet walked past the door, and instead of doing so, he stops when the Blues Brothers ask what's going on. (00:56:14)
Continuity mistake: When Carrie Fisher first attacks the boys with rocket-propelled grenades at the hotel doorway, they dive for the sidewalk and are covered with debris. As they rise moments later and enter the hotel, their black suits and hats are covered in white cement dust. In the immediate next shot, as they climb the hotel staircase, their hats and suits have no dust whatsoever.
Continuity mistake: Near the end of the movie when the brothers are preforming "Sweet Home Chicago", they do a lot of spins and turns. The very last spin they do puts Jake towards the audience and Elwood towards the band. Then the camera angle is changed and Elwood is towards the audience and Jake is towards the band. (01:55:05)
Continuity mistake: When Carrie Fisher is shooting at Jake and Elwood in the tunnel under the Palace Hotel, she hits a water pipe and water sprays everywhere in a mist. In the next shot of Jake and Elwood lying in the mud, there's no spray visible behind them at all. When Jake stands up a few seconds later, the spray is back, but is more directed now. (01:57:39)
Continuity mistake: During the mall chase, a semi-profile shot shows the squad car roll onto its roof and slide with a large panel of orange signage pinned under the roof. Camera cuts to a view of the officers inside the squad car, and there is no signage nor any other debris pinned under the car's roof. Camera cuts back, and the signage is again pinned under roof. Camera cuts back to frontal view, and the signage is gone again.
Continuity mistake: The woman in the car trying to shoot Jake has a couple of errors. First, she gets six shots out of a four barrel weapon without reloading. Second, she goes from having the weapon out of the window, to no weapon and driving in one second, where it took at least five or six seconds to get it out and aim it.