PokerStars is legal in the US for online casino players aged 21 or older. However, it is only legal in 3 states in the US, these being, Michigan, Pennsylvania, and New Jersey.
PokerStars real money is 100% legit. PokerStars has been an industry leader since its launch in 2001. You do not stay as the number one online poker site for more than two decades if you are not legitimate!