Blackjack at JustCasino: Rules, Strategy and Odds
Blackjack can have one of the lowest house edges in the casino, but only when two things line up: the table has good rules, and you play your hands correctly. This guide explains how the game works, the rules that change the odds, the principles of basic strategy, and the bets that quietly cost more than they seem.
It is written to help you understand the game, not to encourage you to play. No strategy removes the house edge.
How blackjack works
Blackjack is played against the dealer, not against other players. The aim is to finish with a hand closer to 21 than the dealer's without going over. Number cards count at face value, picture cards count as 10, and aces count as 1 or 11, whichever helps the hand.
You and the dealer each receive two cards, and one of the dealer's cards is shown face up. A hand of an ace and a ten-value card on the first two cards is a blackjack, which usually beats any other hand. If your total goes over 21, you bust and lose immediately, even if the dealer busts later. That is where the casino's edge comes from: you act first, so your busts count before the dealer plays.
Once players have finished, the dealer reveals their hidden card and follows fixed rules, drawing until reaching at least 17. The dealer makes no choices, so all the decisions in the game are yours.
Your options on each hand
Hit
Take another card. You can keep hitting until you stand or bust.
Stand
Keep your current total and end your turn.
Double down
Double your bet and take exactly one more card.
Split
With a pair, split it into two hands, placing a second bet of equal size.
Surrender
Where offered, give up the hand and get half your bet back.
Insurance
A side bet offered when the dealer shows an ace. Usually worth declining.
The table rules that change the odds
Blackjack rules vary between tables, and small differences add up. Two tables that look identical can differ by more than a percentage point in house edge. Every table's rules panel shows its rules, and these are the ones to check.
| Rule | Better for you | Worse for you | Approximate effect |
|---|---|---|---|
| Blackjack payout | 3 to 2 | 6 to 5 | 6 to 5 adds about 1.4% to the house edge |
| Dealer on soft 17 | Stands (S17) | Hits (H17) | Hitting adds about 0.2% |
| Doubling | On any two cards | Only on 9, 10 or 11 | Restrictions add roughly 0.1% to 0.2% |
| Double after split | Allowed | Not allowed | Allowing it saves about 0.14% |
| Surrender | Offered | Not offered | Late surrender saves a little under 0.1% |
| Number of decks | Fewer | More | More decks slightly increase the edge |
The single most important rule is the blackjack payout. A table paying 6 to 5 is worse than almost any combination of the other rules, so look for 3 to 2 first. Our live casino guide covers how live tables display their rules.
Basic strategy
Basic strategy is the mathematically best decision for every combination of your hand and the dealer's face-up card. It is not a trick or a system. It simply means never giving away more to the house than you have to. Played correctly on a table with good rules, it brings the house edge down to around 0.5%. Playing by instinct typically costs several times that.
The principles below are based on the most common online setup: several decks, with the dealer standing on soft 17. Correct play shifts slightly under other rules, so full strategy charts for each rule set are worth using if you play often.
| Your hand | Dealer shows 2 to 6 | Dealer shows 7 to ace |
|---|---|---|
| Hard totals (no ace counted as 11) | ||
| 17 or more | Stand | Stand |
| 13 to 16 | Stand | Hit |
| 12 | Hit against 2 or 3, stand against 4 to 6 | Hit |
| 11 | Double | Double against 7 to 10, hit against an ace |
| 10 | Double | Double against 7 to 9, hit against 10 or ace |
| 9 | Double against 3 to 6, hit against 2 | Hit |
| 8 or less | Hit | Hit |
| Soft totals (an ace counted as 11) | ||
| Soft 19 or more | Stand | Stand |
| Soft 18 | Stand against 2, double against 3 to 6 | Stand against 7 or 8, hit against 9 to ace |
| Soft 17 or less | Hit, or double against the weaker upcards | Hit |
Pairs: the key rules
Always split aces and eights. Two aces make a weak 12, and two eights make 16, the worst hand in the game. Splitting turns both into better starting points.
Never split tens. A total of 20 is already one of the strongest hands you can have.
Never split fives. Treat a pair of fives as a hard 10 and double against dealer 2 to 9.
Split 2s, 3s, 6s, 7s and 9s selectively, mostly against the dealer's weaker upcards. A strategy chart gives the exact cases.
Many players worry about "wasting" a good hand by standing on 12 against a dealer's 4, or hitting 16 against a 10. Those choices feel wrong but are correct, because they account for how often the dealer busts or makes a strong hand from that upcard.
Insurance and side bets
Insurance
When the dealer shows an ace, you can bet up to half your stake that the dealer has blackjack. It pays 2 to 1. Because fewer than a third of the remaining cards are ten-value, insurance carries a house edge of around 7% in a typical multi-deck game. For basic strategy players, it is always worth declining, including "even money" on your own blackjack.
Side bets
Many tables offer side bets such as Perfect Pairs or 21+3, which pay out on specific card combinations. They offer large payouts but usually carry a much higher house edge than the main game. Check each side bet's paytable before using it, and remember it adds cost to every hand.
Card counting online
Card counting tracks which cards have been dealt to estimate whether the remaining cards favour the player. It is not practical in digital blackjack, where the cards are typically reshuffled electronically before every hand. Live tables commonly use many decks and reshuffle well before the shoe runs out, which also limits counting. Casinos can restrict players they suspect of it, so it is not a realistic path to an edge online.
Blackjack at JustCasino
JustCasino offers blackjack in two forms. Digital blackjack uses a random number generator and plays fast, often with low minimum bets; our games guide covers the digital tables. Live blackjack uses a real dealer streamed from a studio; some tables seat a fixed number of players, while others let many players follow the same hand and make their own decisions. Our live casino guide explains how live tables work.
The exact tables change over time, so check the lobby. Before sitting down, open the rules panel and look for a 3 to 2 blackjack payout, the dealer standing on soft 17, and doubling allowed on any two cards.
Browse the blackjack tables
Check each table's rules panel for a 3 to 2 payout before you play, and set your spending limit first. 18+ only.
Blackjack and JustCasino bonuses
JustCasino's bonuses are designed mainly for pokies, and blackjack is treated very differently under the default bonus terms. Individual promotions can set their own conditions, so always read the terms of the specific offer.
Low contribution
Only a tenth of each blackjack bet counts towards wagering. A A$50 bonus at 40x needs A$20,000 of blackjack bets.
Maximum bet
No bet can exceed A$8 while a bonus is active. Doubling down or splitting increases your stake on a hand, so keep your base bet low enough to stay under the limit.
Betting systems
Low-risk betting systems and sharply cutting stakes after a big win are treated as bonus abuse and can void winnings.
For most blackjack players, playing without a bonus is simpler and avoids the risk of breaching the rules on a double or split. Our wagering requirements guide includes a calculator for blackjack, and our promotions page lists the bonus rules in full.
Blackjack and your budget
A low house edge does not mean low cost. Digital blackjack can deal hands quickly, so the number of hands per hour matters as much as the edge, and doubling and splitting can raise the amount at stake on a single hand. Decide your budget and a time limit before you start, and use the deposit limit tools in your account settings.
If blackjack stops feeling like entertainment, free and confidential support is available around the clock through Gambling Help Online or by calling 1800 858 858. Our responsible gambling page lists more options.
A note on the legal position
JustCasino is licensed in Curaçao, not in Australia, so Australian consumer protections and local complaint processes do not apply to your account. Our licensing and safety page explains what that means.
Frequently Asked Questions
With favourable rules and correct basic strategy, the house edge is around 0.5%. It rises with worse rules, such as a 6 to 5 blackjack payout, and with incorrect play. Players who rely on instinct typically face an edge several times higher.
A blackjack normally pays 3 to 2, so a A$10 bet wins A$15. At 6 to 5, the same blackjack wins A$12. That reduction adds roughly 1.4% to the house edge, which is more than most other rule differences combined.
No. Insurance is a side bet that the dealer has blackjack, and it carries a house edge of around 7% in a typical multi-deck game. Basic strategy is to always decline it, including the "even money" offer when you have blackjack.
Basic strategy is the mathematically best decision for every combination of your hand and the dealer's face-up card. It does not beat the house edge, but it keeps it as low as possible, around 0.5% on a table with good rules.
Not in digital blackjack, where the cards are typically reshuffled electronically before every hand. Live tables usually use several decks and reshuffle well before the end, which limits counting, and casinos can restrict players they suspect of it.
Under JustCasino's default bonus terms, blackjack counts 10% towards wagering, compared with 100% for pokies. The A$8 maximum bet applies while a bonus is active, which includes the extra stake from doubling down or splitting.
Related guides
18+ only. House edge figures are approximate values for typical rules and correct play. Always check the rules panel of the specific table. If gambling is causing harm to you or someone close to you, call Gambling Help Online on 1800 858 858, any time, for free and confidential support.