Continuity mistake: When Melinda Dillon breaks the lamp, it is broken into many pieces, but when Darren McGavin is gluing it back together it is now in much fewer and bigger broken pieces. Obviously different broken lamps were used.
Visible crew/equipment: After Mortimer's comment that Billy Ray has probably been stealing since he could crawl, when it cuts to the two officers opening the squad doors to place Billy Ray at the back of the vehicle, the barndoor set lighting is visible over the squad car at the top right corner of the screen. (00:18:25)
Continuity mistake: When Scrooge walks into the Cratchit home at the end, there is a "Home Sweet Home" plaque on the wall. The shot then cuts away from it. The next time the plaque is visible, its lettering has changed.