Go to your stadium complex and open the balance sheet.

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Here you can set ticket prices separately for league, cup, International Masters and friendly and training matches.

The lower the price, the more spectators will come to your stadium. The number of spectators also depends on your stadium level, the league layer you play in, and your reputation.
The prices for friendly matches should be set rather low, as the spectators will not pay high prices. League matches can be set higher.
For cup and International Masters matches the prices should be adjusted regularly. In the cup the popularity goes up with each round. In the International Masters the turnout will be stable during the group phase and then goes up with each round. 

For regular league matches the home team receives all earnings from ticket sales.
In relegation, friendly, practice and cup matches the earnings are split evenly between the two teams. 
In the International Masters the earnings are also kept by the home team, however, in the final matches there is a fixed income:

  • visitor income for IM Gold final: 1.795.000€ (897.500€ for each team)
  • visitor income for IM Silver final: 1.250.000€ (625.000€ for each team)

Hint: It sometimes can be a good idea to lower the prices if you have a hard and important home match. The home advantage is higher, the fuller the stadium is, so forcing a full stadium by lowering the price can help.

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It is not possible to set prices for United matches. United matches neither have the positive nor the negative effects on your team as regular matches do; and they also do not bring in ticket revenues. They are always played in a neutral stadium, so that no one has the advantage of a home match. Because of this ticket prices for United matches are not needed.