To play through is to use the casino bonus credits according to the wagering requirement.
A wagering requirement (aka ‘wager’ or ‘play-through’) is a multiplier (10x, 15x, 20x, 25x…) that dictates how to turn bonus credits into real money and withdraw it. It determines the amount of credits subject to ‘play-through’ after all the bonus has been used up. The best way to explain the meaning of a wagering requirement is with an example.
Imagine, you got $30 casino credits with the wager = 15x. Do some math: multiply these two numbers 15x$30 = $450. $450 is the amount of casino credits subject to further play-through. After the player has wagered all the $450, all the funds left after the game will be automatically turned into real money and added to the player’s real money balance.