What Is Basic Strategy?

Blackjack is one of the few casino games where your decisions directly impact the house edge. Basic strategy is a mathematically derived set of rules that tells you the optimal action — hit, stand, double, split, or surrender — for every possible hand combination against every possible dealer upcard. Played correctly, basic strategy can reduce the house edge to under 0.5%.

The Core Principles

Before diving into specific plays, understand the foundation:

  • The dealer must hit until reaching 17 or higher
  • You win if your total beats the dealer without exceeding 21
  • Busting (going over 21) means an automatic loss, regardless of the dealer's hand

Hard Hands: When You Have No Ace (or Ace Counting as 1)

Your HandDealer Shows 2–6Dealer Shows 7–Ace
8 or lessHitHit
9DoubleHit
10–11DoubleDouble (hit if dealer has Ace)
12–16StandHit
17–21StandStand

Soft Hands: When You Have an Ace Counting as 11

Soft hands give you flexibility because you can't bust on one more card.

  • Soft 13–15 (A-2 to A-4): Double vs. dealer 4–6; otherwise hit
  • Soft 16–17 (A-5, A-6): Double vs. dealer 3–6; otherwise hit
  • Soft 18 (A-7): Double vs. dealer 3–6; stand vs. 7–8; hit vs. 9–Ace
  • Soft 19–21: Always stand

Pairs: When to Split

Splitting pairs can turn a weak hand into two strong hands — or cost you double if done wrong.

  • Always split: Aces and 8s
  • Never split: 10s and 5s
  • Split 2s, 3s, 7s: Against dealer 2–7
  • Split 4s: Only against dealer 5–6
  • Split 6s: Against dealer 2–6
  • Split 9s: Against 2–9, except 7; stand against 7, 10, Ace

When to Surrender

Not all games offer surrender, but when they do, it allows you to forfeit half your bet rather than play a losing hand. Surrender is recommended with:

  • Hard 16 vs. dealer 9, 10, or Ace
  • Hard 15 vs. dealer 10

Common Mistakes to Avoid

  1. Always taking insurance — The insurance bet carries a high house edge and is not recommended in basic strategy.
  2. Standing on 12 vs. dealer 2 or 3 — Basic strategy says hit here; the dealer is more likely to beat a low stand.
  3. Not doubling on 11 vs. dealer 10 — Doubling is still mathematically correct in most standard games.

Practice Makes Perfect

Basic strategy is most effective when memorized, not just referenced. Many online casinos offer free-play modes — use them to drill these decisions until they become second nature. A printed strategy card is allowed in most brick-and-mortar casinos, too.