Blackjack basic strategy

What blackjack basic strategy is and where it came from

Basic strategy is a lookup table. Down one side is your hand; across the top is the dealer's upcard; each cell tells you the action with the best long-run result. It was first worked out by hand in the 1950s by four US Army mathematicians, often called the Four Horsemen, and later refined with computer simulations that play every situation millions of times.

It answers one narrow question: given only your cards and the dealer's upcard, what loses least or wins most on average? It ignores which cards have already been dealt, which is why it is different from card counting. It also ignores staking, so it says nothing about how much to bet; the house edge explainer covers why bet size cannot fix the odds.

Because charts depend on the rules, always check the game's help screen first. The charts below assume the most common online set-up. If you need a refresher on hand values, hitting and standing, read blackjack rules before going further.

How to read a basic strategy chart

Each chart uses short codes. The column is the dealer's face-up card, with 10 standing for any 10, jack, queen or king. Find your hand in the left-hand column, read across to the dealer's card, and play the code.

Use the pairs chart first if you hold a pair, then the soft chart if you hold an ace counted as 11, and the hard chart for everything else. After hitting, recheck which chart applies: a soft 17 that draws a 10 becomes a hard 17.

Basic strategy for hard totals

A hard hand has no ace, or has an ace that can only count as 1. These hands make up most of your decisions.

The logic is easy to remember once you see the pattern. When the dealer shows 2 to 6, they are more likely to bust, so you stand on stiff hands of 13 to 16 and let them take the risk. When the dealer shows 7 or higher, standing on 16 usually loses, so you hit. The one odd row is 12, where you hit against 2 and 3 because the dealer busts less often with those cards than you might think.

Basic strategy for soft hands

A soft hand contains an ace counted as 11. You cannot bust by taking one card, which makes soft hands the best time to double against a weak dealer card.

Soft 18 is the hand players most often get wrong. Standing feels natural, but against a 9, 10 or ace, 18 is an underdog and hitting improves it more often than it ruins it. Never stand on soft 17: it can only improve or be reset to a hard total.

When to split pairs in blackjack basic strategy

Splitting turns one hand into two, with a second stake equal to the first. This chart assumes you can double after splitting, which most online tables allow.

Two rules stand out. Always split aces, because each ace has a good chance of becoming 21. Always split eights, because 16 is the worst hand in the game and two hands starting on 8 lose less on average. Never split tens or fives: 20 is too strong to break up, and a pair of fives is a 10 that should usually be doubled. Our split glossary entry explains how split hands are paid.

Surrender, insurance and even money

Where late surrender is offered, you can give up half your stake after the dealer checks for blackjack. Use it on hard 16 against a dealer 9, 10 or ace, and hard 15 against a 10. Do not surrender a pair of eights in these games: split them instead.

Never take insurance, and never take even money on your own blackjack against a dealer ace. Both are the same side bet that the dealer holds a 10 underneath. In six or eight-deck games, fewer than a third of the remaining cards are 10-value, so a 2 to 1 payout is too low and the bet carries an edge of around 7%.

Even money on a £10 blackjack pays £10 for certain. Declining it pays £15 most of the time and £0 when the dealer also has blackjack. Over many hands, declining returns more on average.

Adjusting basic strategy for different table rules

Small rule differences change a handful of cells. Use these adjustments when the help screen shows a different set-up.

Rule-changed games have their own strategy. In Free Bet Blackjack, for example, you accept every casino-funded double and split; in Infinite Blackjack, the Six Card Charlie rule shifts a few decisions. Comprehensive charts by rule set are published by Wizard of Odds (opens in a new tab).

How much blackjack basic strategy saves you

Typical figures for a six-deck, 3:2 game with good rules: perfect basic strategy gives an edge of around 0.5%. Players who mimic the dealer by hitting to 17 give the house roughly 5.5%, and players who never bust themselves by standing on 12 or more give it around 4%. Most casual players fall somewhere between, often at 2% or more.

In pounds, at £10 a hand and 300 hands over an evening, total stakes come to £3,000 before doubles and splits. At 0.5% the average cost is about £15; at 2% it is about £60. The cards fall the same way for everyone; what differs is how much each decision gives back. The question which casino games have the best odds puts these numbers alongside other games.

How to learn basic strategy quickly

1. Learn the pair rules first: always split aces and eights, never split fives or tens.
2. Learn soft doubles: soft 13–18 double against 5 and 6, widening to 4 and 3 as the total rises.
3. Learn hard stands: stand on 13–16 against 2–6, hit against 7 or higher, and stand on 12 only against 4–6.
4. Learn hard doubles: 11 against 2–10, 10 against 2–9, 9 against 3–6.
5. Keep the chart open beside the game while you play online. It is not against the rules.
6. Practise on a demo table after age verification until you rarely need to look.

Many players find it easier to learn by grouping the dealer's upcards: 2–6 are weak, 7–8 are middling, and 9, 10 and ace are strong. Demo modes are covered in free to play casino games.

UK rules that apply when you use basic strategy online

Using a strategy chart at a UK-licensed casino is entirely allowed. The rules that matter are about game design and your account.

• Since 17 January 2025, RNG casino games other than slots have a minimum 5-second game cycle and no autoplay, so each hand is played by you at a measured pace. See table game speed rules.
• Your net position and elapsed time are shown on screen during play, following the same 2025 changes to the game design rules.
• You must be verified as 18 or over before playing, including demo games; see casino age verification.
• The slot stake limits do not cover blackjack, so table limits and your own deposit limits set the ceiling.

Full details of the five-second rule are in the Gambling Commission's speed of play consultation response (opens in a new tab).

Basic strategy myths and betting systems

• "The dealer is on a hot streak, so I should stand more." Streaks do not change the next card; the chart already accounts for the dealer's upcard. See the gambler's fallacy.
• "Bad players at the table ruin my odds." Other players' decisions change which cards you see, but not in a predictable direction. Over time the effect averages out to zero.
• "Raise your stake after losses and basic strategy makes it safe." Strategy cuts the edge per hand; progressive staking like the Martingale system still faces streaks and table limits.
• "Basic strategy wins in the long run." It doesn't. It loses slowly. Only card counting in favourable conditions can tilt the edge, and online that is rarely possible.

Where to use blackjack basic strategy in the UK

Look for a 3:2 table where the dealer stands on soft 17 at a Gambling Commission-licensed casino. Our partners all hold UK licences; we don't list their blackjack titles because lobbies change, so check each online blackjack UK table's help screen. More games are in the games hub.

The welcome offers shown below aren't blackjack offers; 18+ and full terms apply. Casumo's is a 50% bonus up to £100 on a first deposit of at least £20, wagered 10x within 7 days with a £5 maximum bet; game restrictions apply. PlayOJO's is 80 spins on Big Bass Bonanza at 10p each for a £10 first deposit, no wagering on winnings, not available in Northern Ireland. Coral's is 100 spins at 10p on selected slots once you deposit and bet £10 on slots, with no wagering on spin winnings.

18+. Gambling should be entertainment that costs money, not a way to make it. Set a deposit limit before you play: how to set deposit limits. Free, confidential help: National Gambling Helpline 0808 8020 133.