Despite the fact that Deacon had dyed Anna's hair brunette, it is back to red when she is in the coffin.
(at around 16 mins) When Anna is lying down on the mortician's table as he takes her black dress off she is wearing black stockings but when he sets it down, on the next scene, her legs are naked.
The scar on Anna's forehead is at times quite smooth and clean, such as when she is lying on the gurney. But when Deacon has her looking in the mirror, and the camera goes back and forth, it appears as a very rough, uneven cut, even with the stitches. Then once again it becomes smooth and clean. Apparently these were from different takes and resulted from different makeup staff.
When Deacon comes into the morgue the very first time, and when Anna's mother goes into the room in her wheelchair, the door opens to the inside. When he leaves after a while, the door opens to the outside. During the rest of the movie the door opens to the inside.
When Deacon leaves to pick up a body, it goes from a quite bright evening to quite dark in between him getting in the car and then driving away from the house. When he goes to fill up petrol just a few minutes later it's fully dark.
Deacon digs up and prepares Anna's grave prior to burial, in fact a grave digger employed by the cemetery is responsible for the task.
(at around 1h 11 mins) The Ohio Bicentennial license plate on Paul Coleman's car is JB751C. Ohio Bicentennial plates were only issued in 2 letter, 2 number, 2 letter combinations. A plate in this sequence would have never been made.
When Paul runs toward Anna's grave, he touches a tombstone which starts wobbling from side to side.
When Eliot leaves, Anna takes the keys and opens the door. You can see the lock is a double deadbolt and requires a key on both sides. As Anna has the keys Eliot could not have locked the door
When Anna is in the coffin for her wake, her eyelids move pretty frequently, even when people are viewing her "body", and no one seems to notice that she's not really dead, yet.
Eliot shoots his victims with a folding packfilm Polaroid, yet the pictures in his wall are integral 600 film - fake 600 integral film. 600 film is black on the back, and when he is looking at Anna's picture the back of the picture is white.
When Deacon placed the burial dress over Anna's body without lifting her body, which require cutting the back of the dress. The back of her dress appears uncut throughout the rest of the film whenever Anna walks.
Around the 28 minute mark, when Elliot is spelling Anna's surname over the phone, he spells it "Tailor" instead of "Taylor"
When Deacon is dressing Anna in the black dress he calls her Emilee, then in the next bit of dialog he calls her Anna again. Neither actor reacts to the wrong character name.