What Are Deviations in Blackjack?

In blackjack, a deviation is when you deviate from the basic strategy of the game. The basic strategy is the mathematically correct way to play every hand, and it is based on the player’s total and the dealer’s up-card.

Deviations can be small or large, and they can be positive or negative.

A positive deviation means that you are doing something that is mathematically incorrect, but it could still be profitable in the long run. An example of a positive deviation would be if you decided to hit on a 16 against a dealer’s 10, even though the basic strategy says to stand.

This is incorrect because hitting has a lower expected value than standing. However, if you hit and happen to get a 20, 21, or even a 22, then you will have won more money than if you had just stood.

A negative deviation means that you are doing something that is mathematically correct, but it could still be unprofitable in the long run. An example of a negative deviation would be if you always split 8s against a dealer’s 9, even though the basic strategy says to stand.

This is correct because splitting has a higher expected value than standing. However, if you split and happen to get two 16s against the dealer’s 9, then you will have lost more money than if you had just stood.

The best way to avoid deviations is to memorize the basic strategy and stick to it religiously. However, even the best players sometimes make deviations, because it is impossible to always make the mathematically correct decision in every hand.

If you do find yourself deviating from the basic strategy, try to make sure that it is for a good reason (like getting better cards after hitting) and not for a bad reason (like splitting 8s against a 9).