In some countries, casinos require players to become members before they will admit them. Applications for membership must be made either in person or in writing, depending on the casino's rules. The straight-forward procedure requires prospective members to give personal details such as name and address, and a declaration that they are old enough to gamble.

The minimum age for gambling is usually the age of majority, commonly 18 years. In the USA players must be over 21, and in Switzerland over 20. Identification, such as a passport or driver's license, may be asked for.

Membership is a legal requirement for entry into most UK casinos. Players must apply 24 hours beforehand and must provide identification. Casinos reserve the right to refuse membership applications. A player who is barred from one casino may find it difficult to obtain membership for another, as the names of barred members often circulate to other casinos within a group or in the same area.