What is bonus wagering and why ido you need to know how it works? A 20x bonus wagering requirement means that you have to wager the bonus money (and sometimes the deposit) a number of times (wagering in the casino) before the money is freely withdrawable.
For example, a wagering requirement of 20x the bonus means that you have to wager the bonus money 20x before it is converted into money, which you can cash out. These wagering conditions have been created by the online casino to prevent players from depositing money, taking the bonus and having everything paid out immediately. In that respect, the wagering is a kind of extra insurance for the casino against bonus abusers. That does not mean that it is impossible to clear casino bonuses, on the contrary. It just means that you have to be careful about which welcome bonuses are interesting and which you should avoid
There are still plenty of good online casinos with a low bonus wagering, if you just look around a bit. A casino welcome bonus is nice to get, but only has real value if you have a realistic chance of clearing the casino bonus.
If the casino bonus has impossible wagering conditions, it is better to skip the bonus completely. Then you at least know that you will not get caught up in annoying wagering conditions the moment you have a nice payout that you have won with bonus money.