A Premier Ball the most basic and essential trainer tool used to capture Pokémon in Pokémon GO. Premier Ball, being the most basic type of ball, has the lowest catch-rate of all Poké Balls. This type of ball can commonly be obtained through various sources in-game.
Premier Balls are used to capture Pokémon from Team Go Rocket Battles and Raid Battles. When encountering a catchable Pokémon, this ball, along with the other types of balls, can be thrown to attempt capture. The Premier Ball will rotate four times before a successful capture, where the Pokémon will break out before four successful movements if unsuccessful. See Catching for more information on how to capture a Pokémon.
Premier Ball can only be obtained via Rocket Battles or Raid Battles. A limited number of these balls are given out for each activity based on the player's performance. Any extra balls after capture are discarded.