When the dealer shows an Ace in blackjack, you may hear a question that sounds reassuring: “Insurance?” If you already have blackjack, the dealer may instead offer “even money.”
Both offers are versions of the same wager: a bet on whether the dealer’s hidden card is worth 10 points. For a basic-strategy player, that wager is normally unfavorable. For a card counter, however, insurance is unusual because the composition of the remaining cards can eventually make it profitable.
This guide explains the mechanics, the math, why even money is insurance in disguise, and the narrow circumstances in which the usual advice can change.
What is insurance in blackjack?
Insurance is an optional side bet offered when the dealer’s upcard is an Ace. At a conventional table, you can generally wager up to half of your original blackjack bet. The insurance wager pays 2:1 if the dealer’s hole card is a 10, Jack, Queen, or King and therefore completes a dealer blackjack.
If the hole card is not a 10-value card, the insurance bet loses. Your original blackjack hand then continues normally.
For example, suppose your main wager is $20:
- You can insure it for up to $10.
- If the dealer has blackjack, the $10 insurance wager wins $20.
- If the dealer does not have blackjack, you lose the $10 insurance wager and continue playing the $20 main hand.
Insurance is therefore not really protection for a weak hand. It is a separate proposition about one unknown card.
The break-even math for insurance
A 2:1 wager breaks even when it wins one-third of the time. If you bet $1 on insurance, there are two outcomes:
- Win: profit $2.
- Lose: lose $1.
At a 1-in-3 win probability, the average result is zero: one $2 win offsets two $1 losses.
That means the important question is not whether your main hand is good or bad. It is simply this:
Are more than one-third of the unseen cards 10-value cards?
Off the top of a fresh shoe, the answer is no. In a six-deck game, for example, an Ace upcard leaves 311 cards before considering the player’s cards. Of those, 96 are 10-value cards. Using only the dealer’s exposed Ace, the chance of a 10-value hole card is 96/311, or about 30.87%—below the 33.33% break-even point.
The exact probability changes slightly once your own cards and other exposed cards are known, but ordinary basic strategy still rejects insurance in a fresh or normally composed shoe.
Why your hand does not make insurance better
A common mistake is to think insurance becomes sensible when you have a large main wager or a strong hand such as 20.
It does not.
The insurance wager is settled solely by the dealer’s hole card. A $100 main bet does not make a $50 insurance bet mathematically safer. A player 20 does not increase the number of 10-value cards remaining. In fact, if your 20 contains one or two 10-value cards, those cards are already unavailable to be the dealer’s hole card.
This is why insurance should be evaluated independently from the emotional value of “protecting” your hand.
What is even money in blackjack?
Even money is normally offered when you have a natural blackjack and the dealer shows an Ace. Instead of waiting to see whether the dealer also has blackjack, you can accept a guaranteed 1:1 profit.
Bet $20, take even money, and you receive $20 of profit regardless of the dealer’s hole card.
That sounds different from insurance, but on a standard 3:2 blackjack it is economically the same transaction.
Why even money is insurance in disguise
Imagine you bet $20 and receive blackjack. The dealer shows an Ace.
If you formally take maximum insurance, you wager another $10:
- Dealer has blackjack: your blackjack pushes, while the $10 insurance bet wins $20. Net profit: $20.
- Dealer does not have blackjack: your blackjack wins $30 at 3:2, while the $10 insurance bet loses. Net profit: $20.
Either way, your profit is $20—the same result as accepting even money.
So when a dealer offers even money, the casino is effectively allowing you to settle the blackjack plus maximum insurance immediately.
Should you take even money?
Under ordinary 3:2 rules, a basic-strategy player should normally decline even money.
Without even money, your blackjack pushes if the dealer also has blackjack and earns its full 3:2 payoff otherwise. Because the dealer’s probability of holding a 10-value hole card is normally below the one-third insurance break-even point, preserving the full 3:2 payoff has the higher expected value.
Using an infinite-deck approximation, the dealer has a 10-value hole card 4/13 of the time and does not 9/13 of the time. Declining even money therefore has an expected profit of:
(4/13 × $0) + (9/13 × 1.5 units) = about 1.0385 units
Taking even money locks in exactly 1 unit. In a finite deck, holding one of the 10-value cards needed for your own blackjack generally makes declining even money slightly more attractive still.
Insurance vs. even money
| Feature | Insurance | Even money |
|---|---|---|
| When offered | Dealer shows Ace | You have blackjack and dealer shows Ace |
| Typical wager | Up to half original bet | No separately displayed wager |
| Winning condition | Dealer has blackjack | Immediate guaranteed settlement |
| Typical result | Pays 2:1 | Blackjack effectively pays 1:1 |
| Basic-strategy advice | Normally decline | Normally decline on a 3:2 game |
The presentation is different, but on a conventional 3:2 blackjack, maximum insurance on your blackjack and taking even money produce the same net outcome.
Why card counters sometimes take insurance
Insurance is one of the clearest examples of the difference between basic strategy and advantage play.
Basic strategy assumes no actionable knowledge about the changing composition of the remaining shoe beyond the cards involved in the current decision. A card counter tracks whether the undealt cards have become unusually rich in 10-value cards.
That matters directly to insurance. Once the proportion of unseen 10-value cards exceeds one-third, a 2:1 insurance wager becomes profitable in expectation.
With the Hi-Lo counting system, insurance is a well-known count-dependent decision. A commonly published six-deck Hi-Lo index is around a true count of +3, although exact indices can depend on the rules, deck count, and the counting/index convention being used.
This does not mean recreational players should guess that a shoe “feels rich in tens.” A genuine insurance deviation requires a counting system, accurate running count, true-count conversion, and an index appropriate to the game. If you are learning deviations, see our guide to blackjack index plays and the Illustrious 18.
Does insurance reduce your losses when the dealer has blackjack?
On an individual hand, yes: a winning insurance bet can offset some or all of the loss on the main wager. That is exactly why the name feels appealing.
But reducing a loss in one particular outcome is not the same as improving expected value.
If the wager pays less than fair odds for its probability, repeated insurance bets cost money overall. The losing insurance wagers in all the dealer-does-not-have-blackjack outcomes outweigh the protection you receive when the dealer actually has it.
This distinction—outcome protection versus expected value—is the central idea to remember.
Does the dealer always offer insurance?
Insurance is associated with an Ace upcard, but casino procedures and blackjack variants differ. In a conventional U.S. hole-card game, insurance is offered before the dealer checks the hole card for blackjack.
Procedures can differ in games where the dealer does not initially take a hole card. If you are playing outside the familiar U.S. format, read our guide to European no-hole-card blackjack and our explanation of dealer peek rules.
The table’s posted rules should always control.
What about insurance at a 6:5 blackjack table?
Do not assume the familiar “even money equals insurance” relationship works identically when a natural blackjack pays 6:5 instead of 3:2.
The standard even-money equivalence depends on the 3:2 main-hand payout, a half-bet insurance wager, and a 2:1 insurance payoff. Change the blackjack payout and the arithmetic changes.
More importantly, a 6:5 payout is itself a major deterioration in the game. Before worrying about insurance, a recreational player should usually prioritize finding a 3:2 table. Our blackjack table-selection checklist explains what to compare, and our house-edge guide shows why payout rules matter so much.
Common insurance mistakes
“I have 20, so I should protect it.”
Your total does not make the insurance side bet pay better odds. Judge insurance by the dealer’s probability of having a 10-value hole card.
“The dealer has had blackjack several times, so insurance is due.”
Past outcomes do not create a guarantee that the next Ace upcard hides a 10. In a freshly shuffled or untracked game, streak-based reasoning does not provide an advantage.
“Even money is free money because I cannot lose.”
Even money removes variance from that particular blackjack, but it also gives up the higher 3:2 payoff when the dealer does not have blackjack. A guaranteed smaller profit can still have lower expected value.
“Insurance is part of basic strategy sometimes.”
For ordinary non-counting play, standard basic-strategy charts tell you to decline insurance. Count-based insurance is an advantage-play deviation, not ordinary basic strategy.
A simple rule for most players
If you are not counting cards accurately, the practical rule is easy:
Decline insurance, and decline even money on a standard 3:2 blackjack game.
Then focus on decisions that actually belong to basic strategy—hit, stand, double, split, and surrender—and on choosing favorable table rules. If you want to understand optional wagers more broadly, see our blackjack side-bets guide.
FAQ
How much can you bet on blackjack insurance?
At conventional blackjack, insurance is generally limited to half of the original main wager. A $20 blackjack bet therefore allows up to $10 of insurance.
What does blackjack insurance pay?
Standard insurance pays 2:1 when the dealer has blackjack. Because a 2:1 bet needs to win one-third of the time to break even, insurance becomes favorable only when the unseen-card composition makes a dealer 10-value hole card sufficiently likely.
Is even money the same as insurance?
On a standard 3:2 blackjack, yes in economic effect. Taking maximum insurance on your blackjack produces a guaranteed one-unit profit whether or not the dealer has blackjack, which is exactly what the even-money offer provides.
Should you insure a blackjack?
A basic-strategy player should normally decline. A skilled card counter may insure when the count indicates enough 10-value cards remain for the wager to have positive expected value.
Can insurance ever be a good bet?
Yes. Unlike many fixed side bets, insurance can become positive expected value when the remaining shoe is sufficiently rich in 10-value cards. That is why card counters use an insurance index rather than automatically refusing it.
Does insurance change how you play your hand?
No. Insurance is a separate wager. If the dealer does not have blackjack, resolve your main hand using the correct strategy for the table’s rules.
Bottom line
Blackjack insurance is a simple 2:1 bet on the dealer having a 10-value card under an Ace. The name makes it sound defensive, but mathematically it is a separate side bet that normally pays less than fair value for a basic-strategy player.
Even money is the same idea packaged differently when you already hold a blackjack. On a standard 3:2 game, accepting it trades the full blackjack payoff for a guaranteed 1:1 win.
For most players, the right default is therefore simple: skip insurance and even money. The meaningful exception is advantage play—when an accurate count shows that 10-value cards are common enough in the remaining shoe to push the insurance wager past its one-third break-even point.
