No, Martingale betting systems are allowed in casinos. The Martingale is legal and widely used around the world. There are no laws or regulations that prohibit its use, and casinos are well aware of the system. While some casinos may frown upon the use of the Martingale system, it is not a bannable offense, and players are free to use the strategy. In fact, the popularity of the Martingale system has led to the development of other similar strategies, such as the Reverse Martingale or the Grand Martingale.