Most online casinos offer some sort of bonus for new customers and of course we are all very happy to get something for nothing but often the headline announcement only tells part of the story. It is prudent to read thoroughly the terms and conditions in detail. As an example, a casino can advertise a joining bonus matching your initial deposit up to 100 Euro. You would therefore expect that when you deposit your 100 Euro they will award you the bonus but not so. Firstly there may be a qualifying play such as you need to play chips to the value of your initial deposit before becoming eligible and even here you need to be careful; it is not unusual for the casino to restrict the games or plays which can contribute to your total. For example playing black/red or odd/even on a roulette table is considered low risk gambling and so will often not qualify at all. Games such as Blackjack, Roulette, Video Poker may only qualify for 50% of your play. You may find that only games such as slots or scratch cards where the casino edge is higher qualify 100%.
Even when you have met this requirement and applied for and/or received your bonus you are still not free to take the money out. You may find that the bonus is placed into a special account and is only available for you to take out as winnings after you have played a multiple of the bonus which can be 10 times or more in other words giving the casino maximum chance of winning it back.
Check the bonuses available by all means but also read the terms and conditions very carefully.