Characters You Thought Were Voiced By Someone Else

[Asa]

Mike in Monsters Inc looks and sounds like he’s being voiced by Nathan Lane (who did Timon in The Lion King films). It’s Billy Crystal doing the voice (clearly, he would make a suitable voice for the meerkat, seeing as how he and Mike sound alike).

 

[Classic Speedy]

Here's one I had recently: The TMNT 2012 episode "Mazes & Mutants" had a character named Sir Malachi, who sounded VERY similar to Trey Parker when he yelled, but he was actually by Paul Reubens.

 

[Darklordavaitor]

Two that come to mind-

-I thought that Eliza of the Tea Timers from Craig of the Creek was voiced by Grey DeLisle, but no, she's voiced by Andree Vermeulen, who I'm not familiar with

-At first, I thought that Kite Man in Harley Quinn was voiced by Dave Willis, since his voice is similar to Barry in Archer, but no, he's played by Matt Oberg.

 

[Classic Speedy]

Another TMNT 2012 one: At first I thought Fugitoid was voiced by Jess Harnell, but nope, it was voiced by David Tennant.

 

[Dr.Pepper]

When I first saw Frozen, I thought that Olaf was voiced by Jonah Hill.