Splitting pairs is the second way to increase a bet after the cards are dealt. Correct splitting strategy can knock another 0.5% off the house edge.
2/2 and 3/3
Both 4 and 6 are weak hands. Only split against a very weak dealer (4–6). If you can double after split, also split against a dealer's 2–3.
4/4
A pair of fours should generally be played as 8. Split only against a dealer's 5–6 when you can double after split.
5/5
Never split 5s. Ten is a much stronger hand than 5. Play 10 — hit against a dealer's 10–A, double against a dealer's 2–9.
6/6
Against a dealer's 3–6, splitting is your best option. Against a dealer's 2, split if you can double after; just hit if you can't. Against a dealer's 7–A, treating 12 as one losing hand beats two 16s.
7/7
Split against a dealer's 2–7 (you hope for two 17s against a dealer's 7). Just hit against 8–A.
8/8
Always split 8s. Eight is always better than 16 — no exceptions.
9/9
A great splitting opportunity:
- •Split against 2–6 (aggressive)
- •Stand against 7 (hope dealer makes 17)
- •Split against 8–9 (you want better than 18)
- •Stand against 10–A (don't risk two losers)
10/10
Never split 10s. A 20 wins most of the time. Casinos only allow you to split 10s because it benefits them — don't fall for it.
A/A
Always split Aces. Two 11s beats one 12 every time. Note: you typically get only one additional card per split Ace.
The Result
By correctly hitting, standing, doubling, and splitting, you reduce the house edge from around 5.5% down to approximately 0.5%. Following these strategies methodically is the foundation of winning blackjack.