Continuity mistake: When the butler takes the mother and kittens to be abandoned in the countryside he is on a motorcycle and sidecar combination. During the trip the sidecar changes from one side of the bike to the other and back again. Also, when the sidecar separates from the motorcycle when the dogs are chasing Edgar, the wheel on the sidecar switches sides regularly as well.
Continuity mistake: When the male kitten plays the piano for his singing sister the painting kitten starts to join him. His paws are covered in paint. During a brief scene change you can see that the colour of the paint on his left paw has changed. Also he only has two colours of paint on him, but minutes later the keyboard is covered in all colours of the rainbow.
Factual error: When Edgar the Butler directs the Old Solicitor upstairs they have a bit of a struggle with the steps. Before this you saw the Solicitor arriving in his car and this gave you an impression how high the first floor of the building of the Old Spinster was. Judging by the amount of steps on the stairs the pair would have ended up on the roof.
Continuity mistake: When the cats jump under the train track, the train goes by. Each time it shows them, they are in a different pose. And when they show the cats again, they are back on the track. They couldn't get up there so fast.
Continuity mistake: When the butler gets placed into the trunk to Timbuktu, from the time he leaves the barn to the moment he gets lifted on the mail truck, a lock magically appears on the trunk.
Continuity mistake: The kittens fight and a candle falls on the floor. The candle is part of the moving parts against the fixed background (decor). In the following shot the candle has become part of the background and thus changes colour and shape. In the next shot when the cats walk away from the area where the candle fell, the candle has disappeared.
Continuity mistake: The painting kitten (in the beginning of the film) steps on a tube of blue paint and squirts a bit that ends up on the floor. Minutes later the colour of the blob on the floor has changed to red and a few moments later the paintblob on the floor has vanished. During the 'paint' scene several tubes near the palette also change colour and position.
Continuity mistake: When Edgard takes the cats to the countryside he looses his shoes in the struggle with the dogs. When he finally leaves the scene his shoes are back again.
Continuity mistake: Marie falls off the viaduct into the river but doesn't get washed along by the current at all (until they spot her and start the rescue that is).
Factual error: In the scene where the three kittens are playing train on the train bridge, Barliose is standing in front, then Toulouse then Marie. After Barliose says, 'Marie's the caboose' you look at Marie's reaction and Barlioses is painted in front on her instead of Toulouse.