Continuity: After Evangeline has left with Aunt Adelaide, Nanny McPhee enters the children's room, and as she and Chrissie walk to the bed they pass Eric's, Lily's and Tora's beds, with the bare wood floor at the center - there is no rug. However, when Nanny McPhee leaves their room the long red and white rug is at the center of the floor, between all the beds.

Visible crew/equipment: After Nanny McPhee and Mr. Brown discuss the subjects of Evangeline's wellbeing with Aunt Adelaide and Simon's cleverness, when Nanny McPhee leaves the room the crew member's movement is seen in the mirror reflection, over the mantle.

Continuity: When Evangeline shows Nanny McPhee the book she is learning to read, the book mark changes between shots as Nanny holds the book up.

Continuity: When Eric, Tora and Aggy are getting ready for bed, Simon walks in and mocks, "And since when have we decided to do what we're told?" The towel to his right (viewer's left) is rumpled up, yet hangs straight in previous and following shots, then is rumpled again.

Continuity: When Nanny McPhee tells Cedric, "Lesson three, to get dressed when they're told is complete," he picks up a pen and fiddles with it. In the next close-up, Cedric's hands are clasped together, and a moment later he picks up the pen and fiddles with it.

Continuity: After Cedric is told that there are no more nannies he comes home, and when Chrissie grabs hold of his leg the teddy jumps off and on the blanket, beside the door.

Continuity: In the wedding scene at the end, a food fight begins and the bride cake topper is knocked off the cake as it ensues. But in later shots it is visible over Simon's shoulder, back on.

Continuity: At Midgewaller & Sons, when Mr. Brown finds the card for the deceased Thadius Quickly, not only does the handwriting differ later at home, but the red swatch pinned to the card differs as well.

Revealing: In the scene where Nanny McPhee seems to suddenly "appear" to Cook, after the children have gotten sick, you can see Nanny stand up from behind the counter, if you watch closely through the red bottle as the camera passes.

Continuity: Near the end, Evangeline has some frosting near the bottom of her nose in a far shot, but when it cuts to a close-up, the blob of frosting is more towards the middle/top of her lip.

Continuity: When the tarantula is crawling on Selma Quickly's hair, Cedric dives onto her. In the first shot his hands are around Selma's neck, as he is falling on top of her, but in the next shot his arms are wrapped around her waist with her arms dangling over his.

Continuity: After Nanny McPhee catches Mr. Brown talking to his wife's chair, and he leaves the room, she looks at the chair and goes to bow. In the close up shot she is starting to lean to the left and in the wide shot she is leaning to the right.

Continuity: When Mrs. Blatherwick sits in the rocking chair in the kitchen, before the "mouse" races across the floor, in the first shot her left hand lies on her belly, with her right hand over her left, patting it gleefully. When it cuts to a close-up, her hands are in the opposite position.

Audio problem: When Simon is sitting on bed, he says "We're getting rid of her tomorrow." However the audio to this line comes a few seconds before his mouth moves.

Deliberate "mistake": Whenever Mr. Brown is at his work in front of a dead man, you can easily see any of the men (if more than one) twitching and breathing. This especially occurs when Mr. Brown is talking to Simon; the man's abdomen is moving.

Continuity: When the Brown kids are making a mess in the kitchen, the bites in the large round bread that Sebastian holds change, and actually become fewer.