There are certain casinos that will do the math for the player so that they know if they have made the wagering requirement. However, there are many more casinos that will simply leave the customer to figure this out on their own. This is why the customers need to read the terms and conditions to see how much they must bet before they can make a withdrawal. They might also need to keep checking how much of that bonus money is in their account because they might have a mix of the two. Players who try to cash out at the wrong time would have a hard time because they only get an email after the fact when the casino figures out that they have not met the requirements. The players have to be very careful because they cannot trust that they have done it right until they wrote down all the math.