Continuity mistake: During the jail breakout, when Jake tries to open the ORV's door, in the shot facing Francis he is holding the gun in his left hand as he tries to open the door for his brother with his right hand. In the next shot facing Jake just before shouts, "I don't have the handle, open the lock!" Francis's gloved left hand is empty, and next shot, the gun can be seen in his right hand. (00:01:45)
Continuity mistake: On the beach, when Mr. Walsh is tearing up the contract we see the bits of torn paper, but when he tosses them in the air there are many more pieces of torn paper up there.
Continuity mistake: After Chunk does the 'Truffle Shuffle' and Mikey releases the bowling ball, we see the horizontal piece of wood that is painted red and attached to the porch rail, from which the silver bucket is lowered. It's seen in many shots. What's funny is that in the first shot of the Walsh's house, after the Fratellis drive past at the bottom of the hill, that piece of wood is white, because it hasn't been painted red yet by the crew. (00:05:10)
Continuity mistake: Outside the lighthouse restaurant as the Fratellis drive away, when Andy and Stef surprise Brand, Mikey and the others, Mikey's yellow rain slicker has a tear a few inches long, at the back of his left sleeve, that mends itself in following shots. (00:36:45 - 00:41:15)
Continuity mistake: At his house, when Brand is working out with the chest expander, in the close-up the black handles are straight bars attached to the springs, but in the wideshot as Mikey conspires with the others to tie up Brand, the handles are now angled and have notches between the springs. (Likely the close-up is a take from the earlier scene when Mouth first arrives.) (00:22:45)
Continuity mistake: When Rosalita (black coat) pours the jewels into Mrs. Walsh's (beige coat) hands in the first close-up, the hand holding the jewels has long nails with colored nail polish. It cuts to a close-up of the Goonies looking down on that hand, and then cuts to a tighter close-up of just the hand holding the jewels, but now there is no nail polish on the thumbnail and the nail is shorter. (01:46:40)
Continuity mistake: On the Inferno's deck, after Mouth spits out the jewels from his mouth, when Andy calls Mama, "You gross old witch," Francis is tying up Andy's hands and his sword is held between his legs, but in the next shot Francis is behind Stef and the sword instantly appears in his hand held high. (01:32:45)
Continuity mistake: When Brand hangs upside down from the bar, we can see that the kitchen table and four chairs are right in front of the kitchen window. But when Mikey unrolls the map in the kitchen, Chunk, Data, Mikey and Mouth are standing directly in front of that kitchen window, which is completely impossible to do. (00:09:40 - 00:22:35)
Continuity mistake: On the deck of the Inferno, when Mama is pulling the pearls from Mouth's mouth, Francis is tying up Andy's hands with black rope. When Mama asks, "Is that all?" the color of the rope is off-white, but it then changes back to the black rope in the following shots. (01:32:30)
Continuity mistake: When Francis Fratelli pours the gasoline in front of the County Jail, there's a parked police cruiser at the corner of the building next door, in front of its windows. After he ignites the fire, there is a close-up of the ORV's tire as the vehicle pulls away, and in the background that squad car is gone, but in the next overhead shot that parked police cruiser is back. (00:02:10)
Continuity mistake: When Mikey turns the 'triple stones' and triggers the large ball, the ball is stained and dull-colored when it begins to roll, then changes to a clean, high-gloss brown as it continues on the track, but reverts back to its original coloring when it falls. (01:10:45)
Continuity mistake: In the beginning, when the Fratellis are eluding the Police, Chunk witnesses the chase. In the first shot the slice of pizza is on the window. Next shot Chunk holds it in the air, and in the third shot the pizza is back in its place where it was in the first shot, with a saucy smear on the window. (00:04:10)
Continuity mistake: When Data's 'bully blinders' are on, just as the bulbs dim, in the close-up Data's cartridge holder hangs over his right shoulder to his left hip instead of the opposite way, as seen in the previous and following shots. Interestingly, this is not due to a flipped shot. (00:48:20)
Continuity mistake: At the start, when Data practices with the blue suction dart, in the close-up as the dart flies out we can see the mechanisms inside Data's invention. When it cuts to a tighter close-up, suddenly there is a spinning spool welded inside, which was not in the previous shot, that is retracting the orange string. (00:03:50)
Continuity mistake: When the kids light the two lanterns they find in the pipe room, they stay lit somehow, even though the lanterns get wet in the well.