How Do Casinos Spot and Catch Card Counters?

Card Counters In The Movie 21. (Image credit: Sony Pictures)
Card Counters In The Movie 21. (Image credit: Sony Pictures)

Once merely an underground practice, the practice of card counting has slowly made its way into the mainstream consciousness over the past decade. Thanks to hit movies like 21 and books like Bringing Down the House, most people, and their mother are at least somewhat familiar with the MIT Blackjack Team and the card counting strategies they used to beat casinos for big bucks all around the world.

But how do casinos catch these card counters in real life, and what happens when they do? While counting isn’t illegal per se (in most places), that doesn’t mean you’ll get off scot-free if you are suspected of doing so. Read on to find out what happens when casinos catch card counters, and how to reduce the chances of getting caught.

Catching Individual Card Counters

Due to the amount of lost revenue at stake, casinos have an ever-increasing number of ways to detect and catch blackjack card counters. While none of these methods are 100% effective, many of the following are incredibly proficient in catching card counters when used in combination with one another:

  • Having the dealer, waitress, or another member of casino staff strike up conversation with you as a way to break your concentration
  • Facial recognition software that can identify blacklisted players
  • Shuffling after a player increases their wager
  • Adding more decks to the shoe to make counting more difficult
  • Making the dealer shuffle the deck more frequently or deal at a quicker pace
  • Flat betting the player (making it so they can’t change their bet amount during a shoe)

However, these countermeasures can come at a cost for the casino. Shuffling more frequently, for instance, results in less hands per hour meaning less revenue for the casino (and risks boring the non-card-counting players).

Some places (like New Jersey) even have limitations on what kind and how many countermeasures casinos can take against proficient players. And while physically harassing a player is a popular way to deal with card counters in movies, doing so in real life could result in a PR nightmare for the casino.

Catching Card-Counting Teams

If you and your buddies dream of teaming together to take the casinos for big bucks, know that (per usual) it’s a lot harder than it looks in the movies. Signaling to other teammates can be incredibly difficult to hide from the watchful eyes of casino security, who often employ former card counters to go undercover on the casino floor and tip off counters to management.

Casinos also share surveillance information about transgressors with each other. Being seen in a number of different casinos together, playing blackjack every time, is a quick way to catch the attention of security and another reason why team card counting is so difficult to pull off.

What Happens if You are Caught?

It’s important to remember that card counting in blackjack isn’t illegal. However, casinos have the right to refuse service to anyone they please, and a number of things are likely to happen if you are pegged as a counter. First, you may just be “asked” to quit playing blackjack or to leave the casino. However, depending on the degree of wrongdoing, the casino could also just outright ban you from the premises.

Facial Recognition” (Image credit:
Facial Recognition (Image credit:

Before you think about trying it: the state-of-the-art face recognition software that most casinos have can easily see past glasses, hats, and other disguises. And getting caught entering a casino you have been banned from is considered trespassing and could land you in jail.

How Not To Get Caught

Successful card-counters can sometimes let their egos get the best of them, which is why it is important to occasionally do some of the following things from time to time in order to make yourself appear like nothing more than a common gambler on a lucky streak:

  1. Screw up intentionally: hit when you shouldn’t and make other beginner mistakes.
  2. Location, location, location: if you keep going to the same tables at the same casino, you are asking to get noticed and caught.
  3. Tip the dealer: treat the dealer well and chances are they’ll be less likely to tip you off to management.
  4. Tip the casino: after you walk away from blackjack (see #5), go lose some money back to the casino on another game like craps or roulette.
  5. Walk away: card counting successfully (and winning in general) can make you feel invincible at the table. Don’t let your pride get the best of you, and know when to walk away (even in the middle of a hot streak).

Again, not being obvious is key. Practice at home until you know blackjack basic strategy like the back of your hand and can see others’ cards in your peripheries without blatantly swiveling your head back and forth.