Basic Blackjack Strategy Overview
Basic Strategy 101 for Blackjack
Basic strategy is a set of rules that tell you the best move you can make, based solely on your hand and the dealer's upcard, in any scenario in blackjack. It uses probability to show when you should:
This is the perfect method to boost your payouts and reduce any losses. Strategy charts based on these rules are also available, so you can start applying basic strategy to your gameplay right away.
Basic strategy was originally created by four mathematicians in the 1950s. Knowing blackjack rules are fixed, they built and tested probability simulations on millions of hands. Basic strategy has been mathematically proven to bring the house edge down from 2% to 0.5%. Players trust it to help them beat the casino more often.
Blackjack Strategy Chart
Basic strategy sheets are the most helpful tools for memorizing these rules. The cheat sheets simply take the rules and lay them out in a color-coded grid to make them easy to read. Strategy cards will tell you when to hit and stand in blackjack, as well as surrender, double down, and split. Every player should have one by their side when playing 21.
Given the number of decks in play can affect your odds of winning, the cheat sheets will reflect these differences, too. Dealer rules, i.e., standing on soft 17, can also affect basic strategy. Most casinos use 6-8 decks in their blackjack games, so our charts cover 4-8 decks and various dealer rules so you can apply basic strategy to most blackjack games.
Blackjack Strategy Cards
4-8 Deck Blackjack, Dealer Hits on Soft 17:
4-8 Deck Blackjack, Dealer Stands on Soft 17:
How to read strategy charts:
Blackjack strategy charts usually follow an XY graph format. To find which move to make, follow the x-axis, or 'player's cards' until you find your hand value. Then look on the x-axis, or 'dealer card' to find their upcard value. Follow the two lines until you reach the cell where they meet. This will tell you the move you should make based on the cards in play.
Blackjack Betting Strategies
Many players try to combine basic strategy with betting systems. These strategies aren't specific to blackjack and use different theories to basic strategy, like progressive betting. Each has its pros and cons and suits different bankrolls and playing styles. Here are the most popular betting strategies in blackjack:
This strategy is hugely popular in roulette. With Martingale, the objective is that you profit from your initial wager, whether that's after the first hand or 20 hands. Here's how the betting strategy works:
- Make a small first wager, say $10.
- If you win, you've succeeded Martingale by guaranteeing your first bet. You can leave, or restart the Martingale strategy.
- Let's say you continue, but lose the next hand. Martingale strategy states you must double your wager on the next hand to try and recoup your losses.
- You double your wager ($20) but lose your hand again. Under the Martingale system, you must double your bet again ($40).
- With Martingale, you double your bet after every losing hand, no matter how many hands you play. When you win a hand, you restart with your original wager.
Does Martingale Work?
The theory behind Martingale is that probability shows players will eventually win and recoup any losses, no matter how many hands they lose. It requires a huge bankroll and blackjack tables with high maximum bet limits to work. For many players, Martingale is too expensive.
1326 Betting Strategy
This progressive betting system advises players should vary their bets to their advantage in the game. The '1326' in the name refers to betting units, and follows a similar, although admittedly more complex, theory than Martingale. Some players might find similarities between the 1326 and Fibonacci sequences.
The probability theory behind 1326 states you are likely to win two hands and lose a third, so you decrease your wager on that hand to maintain some control on your bankroll. Here's the betting system in action:
- Decide on a betting unit amount, then wager one unit on your first hand. In our example, 1 unit = $10.
- If you win that hand, increase your wager to three units on the next round. So, we would bet $30.
- You win the next hand too, making your current profit $40. At this point, 1326 states you should put those profits back in your stack and bet two units ($20) on the next hand.
- If your third hand wins, you're on a winning streak. 1326 says it's time to put all your profit from the current sequence on your next hand, which means wagering six units ($60).
- Let's say you win that hand — you're on fire! You've completed the 1326 sequence and should take your profit off the table and start again with one unit.
- If you lose a hand at any point in the sequence, you start over with one unit.
Does the 1326 Blackjack Strategy Work?
1326 recognizes that you can win four hands in a row, although it won't happen often. When the shoe is hot, it guarantees that you maximize your profit. You don't need a hefty bankroll as 1326 mainly uses your profit.
212 Manhattan Betting System
212 is another progressive betting strategy that uses units, but it is simpler than 1326. Also known as the Manhattan system, this strategy aims to cap your downside, take profit when you win, and maximize your bankroll if you're on a hot streak:
- Choose how much you want your betting unit to be worth. We'll use $10= 1 unit in our example.
- Start the sequence by betting two units, or $20 in our case.
- If you win that hand, you take your profit off the table and drop your bet to one unit on the next hand ($10).
- We are now in the '1' section of the sequence. If you lose, you keep betting one unit until you win a hand. Should you win, you enter the final '2' in the sequence and wager two units ($20).
- Let's say you win this hand as well. The 212 system states you should add one unit to every previous wager until you lose. In our example, we would increase our bet to three units ($30).
- Should you lose, you start the sequence over and bet two units.
Does the 212 Blackjack Strategy Work?
The Manhattan system stays on the safe side and doesn't require a huge bankroll, either. The system lets you capitalize on your hot streak, but the amounts are small. Winning streaks of 6-10 hands don't occur often, so keep your expectations low for this system.
MR BLACKJACK SAYS...
Like any good strategy its more important to understand the concepts than follow the strategy rigidly. 212 minimizes the downside but caps the upside. 1326 has you risking everything on hand number four, and Martingale has you betting over $1,200 within 8 hands.
Every betting strategy is situational. Should the count be excellent on hand four, you may want to bet more than six units. If you lose a couple hands in a row and the cards keep coming out low, you may want to double your bet to make up the loss, like Martingale. The important takeaway is that you combine effective betting with basic strategy and card counting to know when to vary your bet.
What About Side Bets?
You might notice that blackjack basic strategy and betting systems don't mention side bets. Blackjack insurance bets, along with side bets, are created by casinos to give players extra excitement and are an optional addition to 21. These wagers come with their own strategies, which we cover in our Side Bets guide.
Is this going too fast?
Check out Mr Blackjack's guide to playing 21
What Does Surrender Mean in Blackjack?
Surrender is one of the most misunderstood moves in blackjack. In blackjack, surrender allows players to hand their cards back to the dealer. In return, the casino gives the player half their original wager back.
This move is helpful when your hand has low odds of winning. It lets you save your bankroll for when you have the advantage in 21. Many players flinch at the thought of accepting small losses though, even when the odds are stacked against them.
Given surrender mainly benefits players, not all casinos offer it.
It might be tempting to persevere with bad hands, but this approach only increases the casino's edge. Knowing when to surrender will help you play smarter against the dealer, and extend your bankroll for when you have the advantage in the game.
When Should You Surrender in Blackjack?
Blackjack surrender strategy largely depends on the dealer's upcard. Generally, a player should surrender if:
- The dealer has a 9, 10, or Ace and they have a total of hard 16; or
- They hold a hard 15 and the dealer's upcard is 10.
If a casino offers early or late surrender, there are specific strategies you can use, which we cover below.
The key factor to remember in blackjack surrender is that you lose 50% of your wager. That means you should only surrender hands where your odds of winning are overwhelmingly negative (<25%). In these cases, surrendering saves you money in the long run.
Early Surrender Blackjack Strategy
If a casino allows players to early surrender, strategy states they should do so when:
- The dealer has an Ace upcard and the player has a hard 5-7, hard 12-17, or pairs of 3s, 6s, 7s, or 8s; or
- The player has a hard 14-16 or pairs of 7s and the dealer has a 10 upcard; or
- The dealer hits on soft 17 and the player has a pair of 2s.
These rules are for multi-deck blackjack games. When playing single deck blackjack, players should not surrender when they hold 4-10 or 5-9 to the dealer's 10.
Unfortunately, casinos rarely offer early surrender. This rule gives players an expected return-to-player rate (RTP) increase of 0.24% or 0.39%, depending on the dealer's upcard. To offset this gain, casinos will usually include other rules that increase the house edge in their blackjack games.
Late Surrender Blackjack Strategy
Late surrender is much more popular, but strategy rules also vary depending on the number of decks in play and whether the dealer hits on soft 17.
If the dealer hits on a soft 17 and the shoe holds multiple decks, players should surrender based on these hands:
- You hold 15 and the dealer's upcard is an Ace or 10
- The dealer has a 10 and you hold 9-6 or 10-5
- You hold 16 and the dealer has 9, 10, or Ace
In games where doubling after a split is not allowed, players should only surrender to a dealer's Ace if they hold a pair of 8s.
For single deck/double deck blackjack games that hit on soft 17, the rules differ. Players should only surrender when:
- They are dealt 14 and the dealer holds a 10
- The dealer holds an Ace and they have a pair of 7s, 9-6 or 10-5
- They hold 16 and the dealer's upcard is an Ace or 10
Need a refresher?
Brush up on your surrender skills with Mr Blackjack's help
How Does Surrender Affect House Edge?
Early surrender can decrease a casino's edge by 0.63%; late surrender can decrease it by 0.1%. As discussed, early surrender is rarely offered and casinos often compensate for this by including other blackjack table rules that increase their advantage. For some blackjack players, 0.1% may seem low. When combined with perfect blackjack strategy and card counting, surrender strategies can give players a vital edge over the casino.
What is Split in Blackjack?
Split is a move players can make in blackjack. If a player holds two cards of the same value, they can split this hand and are dealt a card for each one, creating two new hands.
Splitting in blackjack attracts an all-or-nothing approach with casual players. Either they split every pair they're dealt, or none at all. Both tactics result in losing blackjack.
You can split pairs to maximize your winnings, but casinos bank on you not learning which cards to do it on. Follow blackjack split strategy rules, and you'll be doubling your payouts on the best hands.
Blackjack Split Charts
Always Split: Aces, 8s
Never Split: 4s, 5s, 10s
|Dealer's Upcard Is:||You Have These Pairs:|
|2-7 inclusive||2s, 3s, or 7s|
|2-6 or 8-9||9s|
When Can you Split in Blackjack?
In blackjack, a player can split their hand whenever they're dealt two cards of the same value. Just because you can doesn't mean you always should, though.
Basic strategy dictates you should always split pairs of Aces and 8s, regardless of the dealer's upcard. These are the best hands to split in blackjack.
A pair of Aces gives a hand value of 2 or 22. Splitting them gives you a greater chance of creating better hands, particularly given the number of cards with a value of 10 in the shoe.
One of the trickiest hands to play in blackjack is a pair of 8s — any additional cards over 5 will bust you. Basic strategy probability states players have a greater chance of winning by splitting this pair and creating new hands.
When Shouldn't you Split in Blackjack?
No matter what upcard the dealer has, you should never split pairs of 4s, 5s, and 10s.
It's impossible for you to hit once and go bust on a pair of 4s. Only three cards can improve a pair of 4s if it's split: a 5, 6, or 7. Unless you're skilled in blackjack deviations, it's not worth the risk.
Players with a pair of 5s have 10. This is a strong position in blackjack, as a hit is likely to give you a high-value hand. Splitting 5s is more likely to leave you with weaker hands, or busting.
Similar to pairs of 5s, a pair of 10s is already a superior hand. As Mr Blackjack always says, the chances of splitting these and being dealt two hands that will both beat the dealer are low.
When Does the Dealer's Upcard Effect Splitting?
In blackjack basic strategy, there are also occasions when players can split satisfactory hands to get a better result. These depend entirely on the dealer's upcard. These split rules dictate:
Dealer upcard 2-7 vs Player pairs of 2s, 3s, or 7s: Split
You and the dealer have low cards. The crucial differences are that the dealer cannot split, and they have to stand on 17. You have a better chance of winning by splitting and forming two marginal hands than standing on a poor hand.
Dealer upcard 2-6 vs Player pair of 6s: Split
6s are the worst bust cards to get. In this scenario, probability states players should split this pair on the chance they are dealt one good hand. This puts players in a good place if the dealer has 16 and busts when they hit again.
Dealer upcard 2-7 or 9-10 vs Player pair of 9s: Split
Generally, 18 is a decent hand that players shouldn't split. In this scenario though, it's likely the dealer will bust. A player can double their winnings with two marginal hands if they split.
MR BLACKJACK SAYS...
As a shortcut, try and think that the dealer has a 10 behind his upcard and that he will get a 10. This is easy when the dealer has a bust card. However, there are occasions when the dealer has a nine or 10 and you will have to split your cards in order to play catch-up and try and break even.
Some blackjack variants and casino table rules restrict how many times you can split. Several casinos only allow players to hit once if they split aces. Others state that after the first split, an Ace and 10-card are considered a non-blackjack 21. Always look for games with the most liberal blackjack rules to get the best payouts.
What Does Double Down Mean In Blackjack?
Double down is a move you can make in 21. After the initial cards have been dealt, a player can make a second bet that matches their ante. In return, the dealer gives them one card — and only one. If their hand beats the dealer, the player wins the wager.
If you're confident you have a winning hand, this bet can give you a welcome advantage over the casino. Before doubling down on every wager though, it's important to be choosy. According to basic strategy, there are only four occasions where players have a good chance of winning this wager.
When Can you Double Down In Blackjack?
You can double down after the dealer has given you your initial two cards. From there, basic strategy advises you to only double down when:
You have a hard 11 versus any dealer's upcard.
The chances of you making blackjack or a similarly superior hand are high.
You have a hard 10 and the dealer shows a 2-9.
It's statistically impossible for you to bust on another card, and it's more likely the dealer will bust trying to reach 17.
You have a hard 9 and the dealer has a 3-6.
Doubling down is a smart move here as the dealer will possibly go over 21 hitting on bust cards.
You have a soft 16, 17, 18 and the dealer has bust cards.
The Ace gives you the flexibility to create a better hand with one extra card, whereas the dealer is more likely to bust.
When Shouldn't you Double Down in Blackjack?
Remember these two rules:
Never double down when the dealer has an Ace.
Even if the dealer doesn't make blackjack, they can still make a good hand with an Ace. Save your bets for when you have the advantage.
Avoid doubling down when your hand value exceeds 11.
Probability indicates you're more likely to bust. In these scenarios, you stand a better chance of winning at blackjack by standing on a marginal hand and letting the dealer bust.
How to Double Down in Blackjack
In the casino, players should double down by adding a stack of chips equal to their original wager to the table. Most dealers understand this signal, but if not, you can also verbalize your intent.
In live blackjack or online 21, simply click 'double down' when the game prompts.
MR BLACKJACK SAYS...
You can't play chicken. No matter what your wager is. If it's time to double down, you have to double. You can't miss these opportunities maximize your profit when its advantageous to do so.
Always check the casino's rules on double down bets first. Some casinos only allow players to double down on hands of 10 or 11, or ban players from doubling down on split hands.
When to Hit or Stand in Blackjack?
Hit and stay/stand are the most basic moves in blackjack, but they cause the most headaches for players when tricky hand values of 14-17 are involved. Perfect blackjack strategy is vital during these moments. It gives you the confidence to know when to trust your hand or take a hit.
Generally, the dealer's upcard determines whether you hit or stay, but these basic strategy rules dictate your action:
You Should Hit When:
Your hand totals 8 or less against any dealer upcard. You can't bust with one extra card.
You have 9-11 against any dealer's card. Even if you have an Ace in your hand you should consider doubling down.
You have a soft 13-19 against any dealer upcard. Consider doubling down if the dealer has a 5 or 6. If you draw a high-value card, the Ace can give you a strong total.
You Should Stay When:
You have 17-20 against any dealer upcard. If the dealer has a bust card, stand on a lower hand and let them bust. Conversely, if the dealer has a high card, you gain nothing by busting out yourself.
You have a hard 13-16 and the dealer has bust cards. Blackjack odds show the dealer is more likely to bust. Stand on a lower hand and reap the rewards for playing strategically.
Our blackjack strategy cards can help you remember these rules, and you can use them while playing blackjack at casinos.
MR BLACKJACK SAYS...
Like in business, sometimes in blackjack it's better to do nothing. Not every decision requires a complicated action. When the math says stay, you must stay. Some NeverSplit10s viewers call this: "Stay and Pray".
Single Deck Blackjack Strategy
Most players know they should choose games with the fewest decks to increase their odds of winning real money blackjack games. However few understand just how big an influence the number of decks can have on basic strategy. Here are the biggest differences, and what to do to make your single deck blackjack strategy a winner:
- Fewer decks mean fewer Aces. This sounds obvious, but removing an Ace from a single deck game of 21 has a bigger effect on the casino's edge than multi-deck versions. Four Aces out of 52 cards gives you a 1/13 probability of getting an Ace. Remove one, and that swings to 1/17. Keep a mental note of the Aces played in the game, so you can track your advantage.
- Single deck blackjack offers more opportunities to double down. There are fewer 10-value cards in the deck, but it is also harder for you to bust. In single-deck games, you can double down on 11, or even 8 as long as the dealer has a 5 or 6.
- You can stand on stiff hands more often. When the dealer has a bust card and you have a stiff hand (12-16), you have a better chance of winning these hands by standing in single-deck games. That's because the dealer has a higher probability of drawing a 10. Our cheat sheet below will tell you the best moments to stand, hit, or split in single-deck blackjack games.
Single Deck Blackjack Chart:
4, 6 & 8 Deck Blackjack Strategy
You already know that more decks in blackjack give the casinos a bigger advantage, but do you know by how much? Knowing how the casino get's its edge between 4, 6, and 8 deck blackjack games will help you improve your basic strategy skills.
The casino's advantage stagnates after more than four decks are added to the shoe. The player's advantage drops most when a second deck is added (-0.33%), but after four decks flattens greatly:
Effect of Decks in Shoe
Numbers of Decks % Change in Player Advantage 1 0.01 2 -0.34 3 -0.45 4 -0.5 5 -0.53 6 -0.55 7 -0.56 8 -0.57
More low-value cards make games run flatter, but if casinos add more than four decks it's to discourage card counters.
More decks mean fewer naturals for you. As mentioned before, more decks mean more low-value cards are diluting the shoe. It's less likely that high-value cards will be dealt with together.
Look for 6-8 deck blackjack games that stand on soft 17 and allow doubling after splitting. Four-deck blackjack games are rare on online casinos, so look for 6-8 deck games with these rule variations. They give players a much better advantage.
Blackjack Deviations Strategy
There will be times when you need to break basic strategy rules in 21. These are called blackjack deviations, and occur when you have a better advantage of winning by contradicting basic strategy.
Blackjack deviations depend on the composition of cards left in the deck. To know when to break from basic strategy, you must be an expert in card counting. If this sounds like you, keep reading to learn how deviation strategies work.
What are Blackjack Deviations?
Blackjack deviations come in two forms:
Playing deviation: If a player makes a move that goes against basic strategy, that's a playing deviation. When the true count changes in blackjack, players can figure out what composition of cards is left in the deck. Instead of relying on probability, players know what cards will be drawn and can change their play accordingly.
Betting deviations: This happens when a player changes their betting style. As you follow the true count in a blackjack game, you will know when you have the advantage. When this happens, you should increase your bets to maximize your winnings and vice versa.
Players can also make betting deviations when managing their bankroll, or to hide their card counting.
How Can Blackjack Deviations Help Your Basic Strategy?
Perfect blackjack strategy reduces the casino's edge by around 0.5%, and card counting gives players a 1% profit margin. While you can get the edge over casinos, it's slim.
Blackjack deviations can give players crucial opportunities to increase their expected value. These only benefit advanced players who know the mathematics to blackjack inside-out, though. For anyone else, deviations can make you lose what little advantage you originally had.
How to Play Blackjack Deviations
The most popular blackjack deviation strategy among players was created by Donald Schlesinger, a professional mathematician, Blackjack Hall of Fame inductee, and author of Blackjack Attack – Playing the Pros’ Way.
Schlesinger explains that only a small number of the total deviation plays were efficient and profitable. He called these the Illustrious 18.
The Illustrious 18 focuses on the variations that give players the highest expected returns. It uses index numbers to identify the true count for when you should deploy these specific deviations. Keep in mind these can alter slightly depending on the number of decks in play.
Here's a cheat sheet with Schlesinger's Illustrious 18 rules:
Blackjack Deviations Chart
Illustrious 18 (Based on Games with >2 Decks)
|2||16 vs Dealer 10||0||Stand at 0 or higher, otherwise hit|
|3||15 vs. Dealer T||4||Stand|
|4||T-T vs. Dealer 5||5||Split|
|5||T-T vs. 6||4||Split if dealer S17|
|6||10 vs. T||4||Double|
|7||12 vs. 3||2||Stand|
|8||12 vs. 2||3||Stand at 3 or higher, otherwise hit|
|9||11 vs. A||1||Double on 1 or higher, otherwise hit|
|10||9 vs. 2||1||Double on 1 or higher, otherwise hit|
|11||10 vs. A||4||Double on 4 or higher, otherwise hit|
|12||9 vs. 7||3||Double on 3 or higher, otherwise hit|
|13||16 vs. 9||5||Stand on 5 or higher, otherwise hit|
|14||13 vs. 2||-1||Stand on -1 or higher, otherwise hit|
|15||12 vs. 4||0||Stand on 0 or higher, otherwise hit|
|16||12 vs. 5||-2||Stand on -2 or higher, otherwise hit|
|17||12 vs. 6||-1||Stand on -1 or higher, otherwise hit|
|18||13 vs. 3||-2||Stand on -2 or higher, otherwise hit|
Using basic strategy helps you make the smartest move on any hand in 21, but there are more ways players can get the edge in blackjack. Learn simple tips to reduce the casino's advantage with our blackjack odds guide.
Card Counting in Blackjack
Basic strategy will help you play smarter blackjack, but you need to learn card counting to beat the casino. When combined with basic strategy, card counting gives players a 1% advantage over the dealer in 21. Despite what Hollywood movies show, anyone can pick up card counting with some practice. Unless you're the Ocean's Eleven crew, card counting is easier than conning the casino.
Other blackjack related articles
Card counting made simple
What should I do after mastering basic strategy?
Once you know basic strategy like the back of your hand, you should learn card counting. There are systems to suit beginner to advanced players, and can give you a crucial edge over the casino.
Where can I find more tutorials on blackjack?
Our Blackjack Academy video hub covers everything you want to know about becoming a winning blackjack player.
Does the dealer hit on soft 17?
Some casinos have table rules stipulating the dealer must hit on soft 17. Players should always check for this rule before joining a game, as it will affect how they play basic strategy.
What is no bust blackjack?
No bust blackjack is a strategy that requires players to stand on busting hands (12-16) in the hopes the dealer busts. The theory behind this blackjack strategy is that players will win more by default just for staying in the game.
What is DAS in blackjack?
DAS stands for 'Double After Split' and the acronym appears frequently on strategy charts. It refers to a rule that lets a player double down after they split a hand.
When does the dealer have to hit in blackjack?
The dealer must hit if their hand totals less than 17 in blackjack. Some casinos have a rule stating the dealer must hit if they have a soft 17 in their hand.
Does dealer hit on 16?
The rules of blackjack force the dealer to hit on 16, even if it's likely they will bust.
What is the payout in blackjack?
Generally, the payout for blackjack is 3:2. Some casinos offer lesser payouts of 6:5, which players should avoid.
What numbers should players split in blackjack?
Aces and 8s should always be split in blackjack as they create stronger hands when combined with nearly any other card. A pair of Aces equals 2 or 22, but when combined with a face card or 10 can give players blackjack. The only way a player can win with a pair of 8s is by the dealer busting. Splitting them allows you to create more competitive hands.
How to calculate house advantage?
To calculate how much the casino takes from your bets as a profit, just multiply the house edge in decimal form with your wager amount. So, if a blackjack game had a 1.5% house edge and you wagered $100, that would be 100 x 0.0150 = $1.50.
What are the odds for blackjack?
The odds in blackjack vary depending on the number of decks in play, table rules, and whether players are using basic strategy. Blackjack has the best odds of winning out of any casino game though, with a house advantage of 0.5-2.0%.