If you lose a battle against a Trainer, what determines how much money you lose? Is it different depending on what game you're playing?
Before Generation IV, half of the money on hand was lost and this loss was not explicitly stated to the player. In FireRed and LeafGreen and Generation IV onward, however, the money lost depends on the level of the player's Pokémon and the number of Badges he/she has earned. In these games, the player receives a message about how much was lost. Prior to Generation VI, the Pokémon will not be given the opportunity to evolve if player blacks out. In the Generation I games, Generation II games, and Pokémon Ruby, Sapphire, and Emerald, the amount of money lost is simply half of the money the player has. In Pokémon FireRed, LeafGreen, and all games from Generation IV onwards, the money lost is calculated using the following formula: Money lost = Level * Base payout Where Level is the level of the player's highest-level Pokémon and Base payout is looked up using the appropriate table below.
source (and table)
