Blackjack side-bet math
Perfect Pairs explained
Perfect Pairs looks only at the player’s first two cards. Both cards must have the same rank; suit and color determine the payout tier.
Three kinds of pair
Same rank and same suit, such as 9♥ and 9♥ in a multi-deck shoe.
Same rank and color but different suits, such as 9♥ and 9♦.
Same rank with opposite colors, such as 9♥ and 9♣.
Exact six-deck fresh-shoe probabilities
After the first card in a complete six-deck shoe, 311 cards remain. Five are perfect matches, six are colored matches, and twelve are mixed matches.
| Result | Matching cards | Probability |
|---|---|---|
| Perfect pair | 5 of 311 | 1.61% |
| Colored pair | 6 of 311 | 1.93% |
| Mixed pair | 12 of 311 | 3.86% |
| Any pair | 23 of 311 | 7.40% |
| No pair | 288 of 311 | 92.60% |
Why the paytable matters
One example pays 25:1 for a perfect pair, 12:1 for a colored pair, and 6:1 for a mixed pair. With six complete decks, that 25/12/6 table has an exact house edge of 19/311, or about 6.11%.
A different 30/10/5 table changes the return even though the cards and probabilities are identical. Always read the actual felt; the name of the wager does not define its payouts.
The side bet does not change basic strategy
Suppose your first two cards are a perfect pair of nines. The pair may win its side wager immediately, but the blackjack hand still follows the normal pair strategy for the dealer up card and table rules. The wagers settle independently.