Blackjack Insurance, Explained
Never take insurance. It loses about 7.7¢ of every dollar bet on it. "Even money" on your blackjack is the same bet in disguise — decline that too.
When the dealer shows an ace, the table pauses and you're offered "insurance" — a side bet of up to half your wager that pays 2:1 if the dealer has blackjack. It's pitched as protection. It's actually one of the most reliably bad bets in the casino, and the math fits in three lines.
The three-line math
- Insurance wins only if the hole card is a ten-value. In a fresh 6-deck shoe that's 96 of 311 unseen cards ≈ 30.9%.
- For a 2:1 payout to break even, the win chance must be at least 33.3%.
- 30.9% × 2 − 69.1% × 1 = −7.4% (−7.69% precisely, accounting for your own cards). You lose ~7.7¢ per $1, every time, forever.
That's the whole story. Insurance isn't "protecting your good hand" — it's a completely separate bet on whether one hidden card is a ten, offered at a price where the house keeps a bigger edge than the blackjack game itself.
"But I had a 20!"
Your hand doesn't matter. Insurance pays based only on the dealer's hole card — your 20 neither helps nor hurts the side bet. If anything, holding two ten-values makes insurance slightly worse, because two of the tens you need are already in your hand.
Even money: the same trap, better marketing
When you have blackjack and the dealer shows an ace, you'll be offered "even money" — a guaranteed 1:1 payout instead of risking a push. Dealers often present this as the smart, safe choice. It is mathematically identical to taking insurance.
| Choice | What happens | Average payout per $1 bet |
|---|---|---|
| Take even money | Guaranteed $1 profit | +100.0¢ |
| Decline | 3:2 if no dealer BJ (~69%), push otherwise | +103.8¢ |
Declining earns about 3.8% more over time. The guarantee feels good; the math pays better. (Our trainer offers the even-money prompt and grades your answer, so the habit gets built correctly.)
The one real exception
Card counters take insurance when the true count is +3 or higher — at that point, the shoe is so ten-rich that the hole card is a ten more than a third of the time, and the 2:1 payout flips profitable. It's actually the single most valuable counting deviation. If you're not counting, the exception doesn't exist for you. (Curious? Here's how counting works.)
Frequently asked questions
How often does the dealer actually have blackjack with an ace up?
About 30.9% of the time in a six-deck game — slightly less than 1 in 3. That gap between 30.9% and the 33.3% break-even is precisely the house's edge on the bet.
Isn't insurance good when I have a big bet out?
No — bet size doesn't change the math of a separate side bet. If your blackjack bet is "too big to lose," the issue is bet sizing, not insurance. Hedging a -EV bet with another -EV bet just loses money twice.
Why do casinos paint the insurance line so prominently on the felt?
Because it's great for them: a built-in 7.7% edge dressed up as a safety feature. The felt is an advertisement.