Insurance is almost always a bad bet when you are playing blackjack. You can find many books and articles that claim that insurance is always a bad wager, but this isn’t true 100% of the time. Never taking insurance is good advice for most blackjack players because they aren’t doing everything in their power to win. If you don’t count cards and/or use other advantage play methods, then you should never take the insurance bet that the dealer offers when she shows an ace. The casino wants you to believe that insurance is an even money bet, and its often called even money
This comes from the fact that when the dealer has an ace showing and completes a blackjack, you lose your original bet and wins the insurance bet, which makes you break even on the hand. This makes blackjack insurance sound like a good bet. The problem is that the insurance bet is just a fancy way of creating a side bet that increases the house edge. When you accept insurance, the bet you are actually making is on the value of the dealer’s face-down card. When the face-down card is worth 10 points, you win the insurance wager, and when it’s not worth 10 points, you lose your insurance wager. Insurance pays 2 to 1, so for the bet to be fair, the odds of the face-down card being a non-10-point card versus a 10-point value need to be 2 to 1 also.
A deck of cards used in blackjack has 13 ranked cards, from two through ace. The deck has four cards that are worth 10 points and nine cards that aren’t worth 10 points. This makes the ratio 9 to 4. This ratio would need to be 8 to 4 to equate to the 2 to 1 payout on insurance, so this is a costly wager. In one of the following sections, I cover counting cards. It’s the most used path to blackjack success and the best one to use to get started. When you count cards, you track the ratio of high to low cards remaining in the deck or shoe.
When the ratio of high cards is much higher than low cards in the remaining shoe or deck, it occasionally reaches a point where insurance becomes a profitable option. This doesn’t happen often, but when it does, the insurance bet should be accepted. After you learn how to count cards, you need to learn the advanced strategy that improves your results. Each card counting system has some advanced plays, usually called index play or indexes, which you use to adjust the basic strategy at certain counts. This is where you find the information about the only times you should accept the insurance wager.