California has set its legal gambling age at 18 to 21 depending on the casino regulations.Washington has set its legal gambling age at 18.South Carolina has set its legal gambling age at 18 (gambling is only legal on cruise ships).South Dakota has set its legal gambling age at 18.Oklahoma has set its legal gambling age at 18.Montana has set its legal gambling age at 18.Minnesota has set its legal gambling age at 18.Kentucky has set its legal gambling age at 18.Idaho has set its legal gambling age at 18.Georgia has set its legal gambling age at 18 (gambling is only legal on cruise ships).The gambling age by state for casinos and legal gambling establishments are listed below. Are you a gambler or do you have ambitions of becoming a professional gambler? Maybe you just like to hit the casino for some fun with friends? Either way, and for whatever reason, you want to gamble or visit the casino, it is important to make sure you are of age to do so first.