When to split pairs in blackjack

The two golden rules

• Always split Aces and 8s. Two Aces are two hands starting at 11. Two 8s make 16, the worst hand in the game: two hands starting from 8 are worth far more.
• Never split 10s or 5s. 20 is an excellent hand; a pair of 5s is a 10 you should double against 2 to 9.

Every pair, card by card

Nines against a 7

Why stand with 9-9 against a 7? Your 18 beats the 17 the dealer most often ends with when showing a 7. Against an 8 or 9, though, 18 is too thin: splitting gives better odds. Against a 10 or Ace the dealer is too strong, so you limit the damage by standing.

Small pairs (2, 3, 4, 6, 7)

These splits are mostly defensive, or exploit a weak dealer. They assume you may double after splitting (the most common rule). If your table forbids it, split less: always hit 4-4, and split 2-2, 3-3 and 6-6 against fewer cards.

Rules worth knowing

• Split Aces: you usually get only one card on each Ace, and Ace + 10 counts as 21, not blackjack (paid 1:1, not 3:2).
• Resplitting: if you receive the same card again, many tables let you split again (often up to 3 or 4 hands), rarely for Aces.
• Double after split: allowed almost everywhere; it's what makes splitting small pairs worthwhile.

In Hitwise, the "Split the hand" button creates two hands tracked separately, each with its own decision.

Frequently asked questions