Card counting is NOT illegal under federal, state and local laws in the United States as long as players don't use any external card-counting device or people who assist them in counting cards. In their effort to identify card counters, casinos can ban players believed to be counters — sort of.

Why is card counting considered illegal?

Using your intellect to count cards can help you win but does not change the game, and is therefore not technically considered cheating. If you cheat, altering the outcome of the game by switching cards with other players or adding cards to the deck, a casino can arrest you.

Is it cheating to count cards?

Card counting is NOT cheating. Card counting is simply using your brain, like a winning chess player. ... The second reason people think card counting is illegal is because… YES, casinos can ask you to stop playing.