Games · Spanish 21
Spanish 21: blackjack minus the tens, plus the comebacks
Blackjack with the four 10-spots stripped from every deck — a 2% gift to the house — and then a rulebook that hands it all back: your 21 always wins, bonus 21s pay up to 3:1, double on anything (and rescue the double when it goes wrong), surrender late, resplit aces. Played with its own strategy, Spanish 21 costs just 0.40% — cheaper than most blackjack actually dealt today. Played with blackjack instincts, it quietly costs double. Our engine derived the right strategy from scratch; the felt will teach it to you.
Set your bet and deal. Spanish deck — the four 10-spots are gone; count on it.
Your move.
Free game, fun credits only. Player 21 always wins; bonus 21s pay up to 3:1 (void after doubling or splitting). Hints show the engine's derived strategy.
The dashed gold line is the published house edge for the selected rules — 0.40% when the dealer stands on soft 17, 0.76% when the dealer hits it. The engine's strategy is derived from first principles and its simulator was verified at ten million hands per rule set. Spanish 21, played well, is one of the cheapest games in the casino — the catch is that "played well" means a hit-heavy strategy most blackjack players find deeply uncomfortable.
Spanish 21 removes the four 10-spot cards from every deck (48 cards; J/Q/K stay) — a change worth about 2% to the house — then hands almost all of it back through rules blackjack players dream about. Played with the right strategy, it's one of the cheapest games in the casino. Every figure below is the published standard, and our engine's ten-million-hand verification reproduces the main-game edges.
(engine-verified: 0.399% at 10M hands)
(the common US floor version)
(exact, 6 decks)
The player rules that give it all back
- Your 21 always wins — even against a dealer 21. Your blackjack always wins and always pays 3:2.
- Bonus 21s: a five-card 21 pays 3:2, six-card 2:1, seven-or-more 3:1. A 6-7-8 or 7-7-7 pays 3:2 mixed, 2:1 suited, 3:1 in spades. (Bonuses are void after doubling or splitting.)
- Double on any number of cards, with double-down rescue — after your double card, you may forfeit the original bet and reclaim the double instead of standing into a disaster.
- Late surrender, double after split, resplitting to four hands — aces included, and you can hit and double split aces.
What the missing tens change
With 12 ten-value cards per deck instead of 16, busts are rarer, dealer totals are weaker, and standing on stiff totals loses value — so correct Spanish 21 strategy hits (and doubles late) far more than blackjack strategy does. Play blackjack's basic strategy here and you give back roughly an extra half percent; the game rewards players who trust its own chart. Our engine derives that strategy from first principles — the Play tab's hints are the derived line, and the derivation independently reproduces published chart features (like surrendering hard 17 against an ace when the dealer hits soft 17).
Match the Dealer — the exact breakdown (6 decks)
| Outcome | Probability | Pays |
|---|---|---|
| Two suited matches | 0.0244% | 18 to 1 |
| Suited + non-suited match | 0.2193% | 13 to 1 |
| Two non-suited matches | 0.3728% | 8 to 1 |
| One suited match | 3.2163% | 9 to 1 |
| One non-suited match | 11.5787% | 4 to 1 |
| No match | 84.5886% | loses |
House edge: 3.06% at six decks (2.99% at eight, where the paytable shifts to 3/12/24). Every probability above is closed-form combinatorics over the Spanish shoe — and they match the published figures to six decimals. As side bets go it's mid-priced: cheaper than most, still seven times the main game. The main game is the bargain here.
Where Spanish 21 sits
| Game, played well | House edge |
|---|---|
| Blackjack, 3:2 S17 (basic strategy) | ~0.5% |
| Spanish 21, S17 | 0.40% |
| Spanish 21, H17 | 0.76% |
| Baccarat (Banker) | 1.06% |
| Three Card Poker (Q-6-4) | 3.37% |
Yes — an S17 Spanish 21 table, played with its own strategy, is cheaper than most blackjack games actually dealt today (which are often 6:5 or H17). The catch is entirely in the word "played": the hit-heavy chart takes real discipline. That's exactly what the Play tab's hints train.
How this simulation works
- Rules modeled
- Spanish 21 on six 48-card Spanish decks (all four 10-spot cards removed; J/Q/K remain, value ten). Player 21 always wins; player blackjack always wins and pays 3:2. Bonus 21s: five-card 3:2, six-card 2:1, seven-or-more 3:1; 6-7-8 and 7-7-7 pay 3:2 mixed / 2:1 suited / 3:1 in spades — all void after doubling or splitting. Late surrender; double on any number of cards with double-down rescue (forfeit the original bet, reclaim the double); double after split; resplit to four hands including aces, which may be hit and doubled. Dealer peeks for blackjack; S17/H17 selectable. Optional Match the Dealer side bet (6-deck table 4/9/18). Stakes are fun credits in integer cents.
- Assumptions
- Hands are independent within a penetrated shoe (reshuffle at 75% dealt). No redoubling (matching the published no-redouble figures). The strategy is DERIVED by the engine's EV recursion over Spanish-deck ratios rather than transcribed from a chart; known approximations, stated openly: decisions ignore the tiny 6-7-8/7-7-7 tier EV (settlement still pays every tier exactly), splits use a split-once EV model applied recursively to the four-hand cap, and a handful of fine composition exceptions in published expert charts (e.g. hitting a multi-card 17 vs an ace) are below the derivation's resolution. Fun credits only, no real money.
- Mathematical basis
- Two verification layers. Match the Dealer is EXACT closed-form combinatorics — the engine's per-outcome probabilities match the published tables to six decimals (edges 3.06% at 6 decks / 2.99% at 8). The main game is verified by seeded Monte-Carlo: the derived strategy, played over a real finite shoe with fully exact settlement, must land on the published house edges — S17 0.40% and H17 0.76% — and does (10 million hands per rule set: S17 observed 0.399%). The derivation also independently reproduces published chart features, including surrendering hard 17 vs an ace under H17.
- Engine version
- spanish-21 engine 1.0
- Validation
- 18 unit tests + a 2×10M-hand slow verification — the Spanish shoe (48-card decks, no 10-spots), every settlement rule (21 always wins incl. vs dealer 21; each bonus tier incl. suited/spades 6-7-8 and 7-7-7; bonuses void after double/split), the exact Match the Dealer probabilities vs the published six-decimal figures, dealer-distribution sanity across all upcards under both rule sets, derived-strategy checkpoints (hit 12v6, hit soft 18 vs A, split A-A/8-8, H17 surrender 17 vs A), determinism, and MC convergence to both published edges.
- Last reviewed
- Verified against published anchors on every layer that admits one (exact MTD probabilities; two published main-game edges at 10M hands each; derived-strategy chart features). Building on the QC'd blackjack engine's primitives. Last reviewed 2026-07-21.