Blackjack Basic Strategy

Written & tested by James Carter iGaming analyst · 9 years reviewing offshore operators

Blackjack has the lowest house edge of any game in the casino — around 0.5% with correct basic strategy on favourable rules. That is roughly a fifth of what roulette costs you and a tenth of a typical slot. The catch is that the 0.5% assumes you play every hand correctly, and most people do not.

Basic strategy is not a system or a theory. It is the mathematically proven best decision for every combination of your hand and the dealer's upcard, calculated by simulation. There is nothing to believe in — it is arithmetic.

The rule that matters more than your play

Before any of the chart matters, check what a natural blackjack pays. 3:2 is standard. 6:5 roughly triples the house edge on an otherwise identical table.

On a 3:2 table a £10 blackjack pays £15. On 6:5 it pays £12. Same dealer, same cards, same decisions — you simply lose more. It is the single most expensive detail in any casino and the easiest to walk past.

The basic strategy chart

Read your hand down the left, the dealer's upcard across the top. H = hit, S = stand, D = double (hit if not allowed), P = split.

Hard totals

Soft totals (a hand containing an ace counted as 11)

Pairs

The four rules that carry most of the value

1. Always split aces and eights. Two hands starting with an ace beat one soft 12. Two hands of eight beat one hard sixteen, the worst hand in blackjack.
2. Never split tens. Twenty is already a winning hand. Breaking it up to chase two more is the most common expensive mistake at any table.
3. Never take insurance. It is a side bet on the dealer having blackjack, and it carries a house edge of around 7%. It is not insurance in any meaningful sense.
4. Stand on 17 or higher, always. Whatever the dealer is showing.

Card counting online — the honest answer

Counting works in principle: track the ratio of high to low cards and bet more when the remaining shoe favours you. In a physical casino with a hand-dealt shoe it is a genuine, if difficult, advantage play.

Online it does not work, for three separate reasons. RNG blackjack reshuffles a virtual deck after every hand, so there is no count to keep. Live dealer games use continuous shuffling machines or reshuffle at a shallow penetration point, which erases the advantage before it accumulates. And the maximum bet spread you would need to profit is exactly the pattern operators watch for.

Anyone selling you an online counting course is selling you something that stopped being true two decades ago.

Where the table rules actually differ

UK-licensed and offshore casinos frequently run the same Evolution live tables, so the rules are often identical. What changes is the ceiling — offshore tables accept considerably higher stakes on the same feed. Our blackjack not on GamStop page covers which sites carry which tables.

Whichever you play, check the blackjack payout before you sit down. Everything else on this page is worth less than that one line of small print.

Why the chart says what it says

Basic strategy is not opinion, and every entry has a reason. Three principles explain almost all of it.

The dealer's bust card

A dealer showing 4, 5 or 6 is in trouble — those upcards bust roughly 40% of the time, because the dealer must hit until 17. That is why you stand on 12 through 16 against them, hands you would otherwise hit. You are not trying to make a good hand; you are declining to bust while the dealer probably will.

The ten-heavy deck

Sixteen of the 52 cards are worth ten. So the working assumption behind most decisions is that the next card is more likely to be a ten than anything else, and that a dealer's hole card probably makes their total ten higher than the upcard shows.

Doubling is about the dealer, not your hand

You double on 11 against almost everything because a ten gives you 21. You double on 9 only against 3 through 6, because those are the upcards where the dealer is weak enough to justify committing more money to a hand that is not yet strong.

The mistakes that cost the most

Bankroll and bet sizing

Blackjack's low edge is only an advantage if your bankroll survives long enough for the average to matter. Variance in blackjack is lower than in slots but far from absent — losing eight hands in a row happens regularly.

The rule of thumb is a base bet no larger than 2% of your session bankroll. Below that, a normal losing run ends the session before the maths has a chance to work.

Side bets — the honest verdict

Perfect Pairs, 21+3, Lucky Ladies, Bust It. Every one carries a house edge between 3% and 12%, against the 0.5% of the main game.

That means a £1 side bet on every hand can cost more than a £20 main bet, because the edge is twenty times higher. They exist because they are profitable, not because they are good value, and adding them undoes the entire reason to play blackjack rather than a slot.

Live dealer blackjack — what to check

• The payout on a natural. 3:2 or walk away. This overrides everything else on the table.
• Soft 17. Dealer standing is better for you by 0.22%.
• Deck count. Fewer decks favour the player slightly; eight is standard and the worst common configuration.
• Double after split. Small but free.
• Surrender. Rare online, worth 0.08% when offered.
• Table limits. Offshore tables typically accept far higher stakes on the same Evolution feed than UK ones.

Variants worth knowing and one to avoid

Lightning Blackjack adds multipliers funded by a mandatory side fee on every hand. Fun, and materially more expensive than standard blackjack — treat it as a different game rather than a version of this one.

Infinite Blackjack lets unlimited players play one dealer hand. Rules are standard; the pace is slower, which is not a bad thing.

Blackjack Party and similar entertainment tables usually run 6:5 payouts. The atmosphere costs 1.39% of your money per hand.

Practising the chart

Nobody memorises it in one sitting and nobody needs to. Learn it in this order and you will cover most of the value quickly: always split aces and eights, never split tens, never take insurance, stand on hard 17 or more, hit hard 12–16 against a dealer 7 or higher, stand on them against 2 through 6.

That handful of rules gets you most of the way from a 2% edge to a 0.6% one. The rest of the chart closes the last fraction.