Blackjack Insurance: Is It Worth Taking?
When the dealer shows an Ace, you'll be offered insurance — a side bet that pays 2:1 if the dealer has blackjack. The casino frames it as protection. The math frames it as one of the worst bets on the table.
21simulator.com tracks insurance EV separately so you can measure the real cost of taking it every time.
What Insurance Is
When the dealer's upcard is an Ace, they offer players the option to place an insurance bet before checking their hole card. The insurance bet is capped at half your original wager. If the dealer has blackjack, the insurance bet pays 2:1. If the dealer does not have blackjack, you lose the insurance bet and play continues normally.
Insurance is mechanically a separate bet on whether the dealer's hidden card is a ten-value (10, J, Q, or K). It has nothing to do with insuring your original hand — the name is marketing.
The Math: Why Insurance Loses
In a freshly shuffled 6-deck shoe, there are 312 cards total: 96 ten-value cards (4 suits × 4 values × 6 decks) and 216 non-ten cards.
When the dealer shows an Ace, one card is removed from the deck. The remaining 311 cards include 96 tens. The probability the hole card is a ten-value:
Insurance pays 2:1. For insurance to break even, the dealer would need blackjack at least 1 in 3 times (33.3%). At 30.86%, you're below the break-even threshold. The insurance house edge:
Insurance has a house edge of approximately 7.4% in a 6-deck game — roughly 15× worse than the game itself. Single-deck insurance has a lower house edge (~5.9%) because fewer non-tens are available, but it's still a losing bet for a basic strategy player.
Even Money: The Insurance Trap for Blackjack Hands
"Even money" is what a dealer offers when you hold a blackjack (natural) and the dealer shows an Ace. The dealer is offering to pay your blackjack immediately at 1:1 rather than waiting to see if they also have blackjack (which would result in a push).
Even money is mathematically identical to taking insurance with a blackjack hand. Accepting it is always a mistake for a basic strategy player. Here's why:
- If you take even money, you always collect 1 unit.
- If you decline, you collect 1.5 units (the 3:2 blackjack payout) 69.14% of the time, and push (collect nothing) 30.86% of the time.
- Expected value of declining: (0.6914 × 1.5) + (0.3086 × 0) = 1.037 units
Declining even money yields 1.037 units expected vs 1.00 unit guaranteed. The casino frames it as risk elimination — you're actually accepting less money to avoid phantom variance.
When Insurance Is Correct: Card Counting
Insurance becomes profitable when the remaining shoe is rich in ten-value cards — when the true count rises high enough that tens comprise more than 1/3 of the remaining cards. This is the only scenario where insurance has positive expected value.
In the Hi-Lo counting system, the insurance index number is +3: take insurance when the true count is +3 or higher. At that count, tens make up approximately 33–35% of remaining cards, and insurance flips to a player advantage of roughly 0–2%.
This is entry #1 in the Illustrious 18 — the most valuable count-based deviation from basic strategy. For non-counters, never take insurance.
The "Good Hand" Fallacy
Players often feel more tempted to take insurance when they hold a strong hand (20, 19, or a blackjack). The reasoning: "I don't want to risk losing this hand." But the insurance bet is statistically independent of your hand. The probability the dealer has blackjack does not change based on what you're holding. Strong hands feel more worth protecting, but that feeling has no bearing on the EV of the insurance bet.
The single exception is if you're counting and tracking the remaining composition — your hand's cards have been removed from the shoe and that changes the true count calculation. But the correct response is to consult the count, not to take insurance based on your hand's strength.
Summary
- Insurance: Never take it (basic strategy).
- Even money: Never take it (basic strategy).
- Counting exception: Take insurance when true count ≥ +3 (Hi-Lo).
- House edge on insurance: ~7.4% in a 6-deck game.
If you find yourself at a table where the dealer heavily encourages insurance, treat it as a signal: the casino knows it's profitable for them. Every dollar you put in the insurance circle is a dollar working against you.