Sport betting is illegal in every state of USA but las Vegas except for sports lotteries which are done in very few states. is illegal to bet online and with bookies. You might bet with a friend as long as there is no bookie in the middle. The use of the bookie make it illegal. You also can bet in certain cruises or ships as long as you are 3 miles offshores. It will be consider a misdemeanor outside of las Vegas if you get caught. Even calling someone in las Vegas to take your bet is illegal as not telephone or internet may be used to place bets outside of Las Vegas. Why 15 millions of americans bet even though it is illegal? because illegal betting hasn't been a priority of the goverment, the police force or any other institution in the country. Besides if it was legal the numbers of american betting would probably be 150 millions not 15. Should you bet? If you are young and want to work in workplaces where a measdemeanor will affect your chances of being hire you might consider avoid betting. Yes the chances of getting caught are very low, but your chances of winning in the long run are even lower. The statute of limitation for illegal betting is 1 year. So if you stop betting now in 12 month you are innocent of all counts even if you get caught.