Blackjack Insurance

When the dealer shows an Ace in blackjack, you're offered insurance. It's a side bet, usually costing half your original wager, that pays 2:1 if the dealer's hole card is a 10-value (giving them blackjack). The idea sounds reasonable: protect yourself against the dealer's strongest possible hand.

The problem is the math. In a standard 6-deck shoe, there are 96 ten-value cards out of 312 total. After removing the dealer's Ace, the probability of a 10 underneath is 96/311, or about 30.9%. For the insurance bet to break even, you'd need the probability to be 33.3%. It's not. The house edge on insurance is roughly 7.4%, making it one of the worst bets at the blackjack table.

Basic strategy says decline insurance every time. The only exception is if you're counting cards and the count is high enough that you know the shoe is rich in 10-value cards. For everyone else, just say no.