Other mistake: At the beginning of the episode, when the mermaid goes underwater, she holds her breath.
The Legend of Sleepy Halliwell - S6-E14
Other mistake: In previous episodes it is stated that good witches don't freeze. But after Piper has been decapitated and her head is placed in the manor, one of the students freezes all the kids by tapping into Piper's freezing power. The kids are all good witches so they should not have frozen.
Siren Song - S5-E4
Other mistake: When the siren gets the pole that was speared through her pulled out, there is only blood in the middle part of the pole. If it had really been pulled out of her, it would be bloody all the way along. (00:19:55)
Other mistake: Paige's spell causes Darryl to acquire invulnerability and uncontrollable super strength. When he opens the door of the squad car, he accidentally rips it completely off. When he tries to put the suspect into the back seat, the man flies through the car and barrels out the other side, taking the other door with him. But immediately before this, Darryl high-fives several of his fellow officers, and they are unharmed. They should have been thrown off their feet and suffered multiple fractures in their hands.
The Legend of Sleepy Halliwell - S6-E14
Other mistake: When Phoebe arrives back from her vision quest to find Piper has been kidnapped she tries to sense from the frozen students which one created the headless horseman. As Gideon, Paige, Chris and Phoebe walk into the conservatory you see Zachery blink rather obviously.
Crimes and Witch-Demeanors - S6-E19
Other mistake: At the end, it shows the Charmed Ones orbing out of the trial, but Chris and Leo never leave. Right after the Charmed Ones orb out, Barbas begins discussing his evil plans with Gideon, so wouldn't Leo and Chris find out that Gideon is plotting against them? After they talk, the camera pans out and Chris and Leo are not there. I guess they just forgot to put in the scene where they leave.
Coyote Piper - S3-E9
Other mistake: At the beginning of this episode, Tara and Kierken are arguing and Kierken says that he could always "suck you into your little mixing bottle and start again." Then Tara says that "she has a better idea," and then she stabs herself. The life essence automatically flows out of her but the knife was still in her body. Later, the possessed business man stabs himself in front of Piper and she kneels down to see if he was okay and the essence flew into her, without the knife being removed from his body. At the end, when Leo comes down after Prue stabs the possessed Piper, he kneels over her, but the essence does not flow into him. It only flows into him after he takes the knife out of her body.
Other mistake: If all the objects in the fortress are originals from the fairy tales, why are the ruby slippers red? In the original story the slippers were silver, they were made red for the MGM movie, so they would be the brightest thing on the screen.
Sleuthing With the Enemy - S3-E8
Other mistake: When Piper puts the Belthazor flesh into the Belthazor vanquishing potion, she is the only one that gets "blasted" back even though she is the one standing farthest away from the stove and the potion.
Other mistake: During the second attack on Wyatt, when he lets his force field down the top of head is transparent from the special effects.
Other mistake: Approximately four minutes into the episode, two demons go to the manor. Pru catches them and "throws" them to the one side. Her arm motion would fling them to the right, but they fly to the left. (00:04:15)
Other mistake: At the start of the episode when Prue and Phoebe are walking down the street (just before they find the box), the person with the green jacket on (in the background) reaches into the homeless man's hat and just "scrapes" the bottom of it. Not putting any money in, or taking any money out - a completely pointless action. (00:02:05)
It's A Bad, Bad, Bad, Bad World (1) - S6-E22
Other mistake: Isn't it amazing that both evil Paige and good Paige have the same exact rocks on their "sides" when they're fighting in the underworld?
Other mistake: The one demon that knew about the 40s party was vanquished, and he went straight from spying on Paige and Phoebe at P3 to "glamouring" into Leo at the Manor. He had no way of telling Devlin about the 40s party, and yet it was still full of demons waiting to kill the Charmed Ones, with Devlin "glamoured" into Melody as a trap. And Devlin didn't even have that power - the demon that was vanquished did.
Charmed and Dangerous - S4-E13
Other mistake: In this episode, the Source talks about the "Ultimate Power" being the Hollow. But in Season 8, we learn that the "Ultimate Power" is Billy and Christy. (And they end up taking in the Hollow, so now are they the "Ultime Power" times 2?) Which is it? It can't be both. (00:02:05)
Other mistake: When Andy, Phoebe and Prue are in the attic figuring out how to vanquish the ghost of Alcatraz, pages starts flipping, the book opens up to the page where the truth spell is, and Andy finds out that Prue cast that spell on him. Later when he asks how much time Prue gave him to react, she says "a minute or two". But in the episode "Truth is out there" (1-8) it was first in Prue's office when she told him, and the clock on the wall shows that it's 25 past 5. And it was 8 o'clock when Prue cast that spell. So few hours later when Andy and Prue are at Andy's door, it's almost 8 o'clock and Prue says she needs the answer now. So doesn't Andy have more like few hours rather than few minutes to react?
Pre-Witched - S3-E17
Other mistake: During a flash back of Grams in the kitchen she puts a rose in a pot, then Piper walks in, they talk and Piper starts to add some salt and a couple other ingredients into the pot. Grams asks how she knows what to add, Piper says says something about mustard - Piper wouldn't know what's in it already, she just walked in. And she never even finds it strange that there's a rose with a stem in it.
Other mistake: This entire episode the ghost brothers whine that Leo is responsible for them dying and he left them to die, even Leo believes this. It makes no sense. As we see in the flashback even if Leo stayed to help they were blown up moments later and still would have died.
We're Off to See the Wizard - S4-E19
Other mistake: Leo tells Phoebe that fire throwing is an upper level demon power, but we know Phoebe had that power in her past life, Piper even reminds her of this earlier in the episode.
Sleuthing With the Enemy - S3-E8
Other mistake: Cole is supposed to be one of the most powerful demons alive, but a small cut from Piper weakens him to the point where he can't even shimmer or keep up his "Cole" appearance.