21+3

A blackjack side bet that combines your two cards with the dealer's up-card to form a three-card poker hand, paying if that hand is a flush, straight, three of a kind or better.

Definition

The 21+3 side bet is placed with the main blackjack wager and is settled using the player's two cards plus the dealer's face-up card. If those three cards make a poker combination, the bet pays according to a scale that typically rewards a flush, straight, three of a kind, straight flush and suited three of a kind, with higher payouts for rarer hands. Paytables vary widely, so the house edge differs a lot between versions, but like most blackjack side bets it is considerably higher than the main game's edge. The bet is resolved immediately after the initial deal and has no effect on how the blackjack hand itself is played.

Worked example

Your two cards are the seven and eight of clubs and the dealer's up-card is the six of clubs. Those three cards form a straight flush, one of the top-paying 21+3 outcomes, so your side bet is paid at the high multiple on that paytable, entirely separately from whether your blackjack hand wins.

Why it matters

For learners, 21+3 illustrates how side bets layer a different game (three-card poker) on top of blackjack at a worse edge. For professionals, its wide paytable variation makes it a good example of why a bet's name alone never tells you its true cost.

Related

Note: 21+3 house edge depends heavily on the specific paytable and deck count, commonly ranging from roughly 3% to over 13%.