For the actors who play the voices of the main Simpsons characters, Dan Castellaneta, Julie Kavner, Nancy Cartwright, Yeardley Smith, Hank Azaria, and Shearer’s, get paid about $300,000 per episode. Originally in 1989 they earned about $30,000 per episode until 1998 when it got moved up to $125,000 for every episode. In 2004 they were threatening to start a strike and so the amount of money they would get paid, moved up to between $250,000-$360,000 and then in 2008 their salary increased to $400,000 but then in 2011 it decreased to $300,000 and it has stayed like that. So their salary has been moved up and down but they do make a lot of money for every episode they make. All of the voice actors had to take a paycut to continue the show.
Since The Simpsons show has been aired, it has profited about $1 billion. The voice actors also get money for merchandise that is sold and commercials about The Simpsons. The Simpsons show became expensive to produce and so thats why the studio has been reducing the show's cost over the years. The Simpsons audience has reduced by almost 20% over the last 5 years and so that's why Fox wants to make them to take a pay cut. When the actors were getting paid about $400,000 and $440,000 the studio wanted to cut that by 45% to about $240,000 per episode and the producers and other people involved had to take the pay cut too. The actors didn't like this and instead of being paid $250,000 they got paid $300,000 instead.