Blackjack Side Bets — 21+3, Perfect Pairs & the Odds

Side bets are the optional wagers offered alongside the main blackjack hand — 21+3, Perfect Pairs, Buster and others. They are fun and can pay big, but every one of them carries a much higher house edge than the base game, and none of them changes how you should play your hand.

The common side bets

• 21+3 — your two cards plus the dealer's up-card make a three-card poker hand (flush, straight, three of a kind, straight flush). House edge typically ~3–7%.
• Perfect Pairs — your first two cards form a pair, paying more for matching colour or suit. House edge typically ~4–11%.
• Buster — pays when the dealer busts, scaling with how many cards the dealer used. House edge typically ~6–18%.

Each pays out rarely and big, which is why the house edge is so much higher than the base game's ~0.5%.

Why basic strategy ignores them

Side bets are settled before or independently of how you play your hand, so they do not interact with your hit/stand/double decisions. Optimal basic strategy and the EV of every action are exactly the same whether or not you place a side bet. That is why Fullcount computes base-game EV and treats side bets as a separate proposition — they are not part of the base RTP:

The honest verdict

A side bet costs you several percent of every dollar staked on it, versus about half a percent on the main hand played with good rules. They are entertainment, not edge — a counter can sometimes beat a few of them with a dedicated count, but for normal play they are the worst money on the table. Keep your bankroll on the base game and size it with a bet spread if you count.