The Martingale strategy doubles the bet after every loss, so the first win recovers everything lost plus the first stake. It does not change the house edge. On a European wheel the expected result is -2.7% of all money bet, and on an American wheel it is -5.26%, the same as betting flat. In our 100,000-session simulation on a European wheel, 82.8% of sessions ended $100 up and 17.2% ended in a loss averaging $588.74.
How the martingale strategy works
The system is one rule. Bet $5 on red, and after every loss bet double the last stake. After a win, go back to $5. An even-money bet pays 1 to 1, so the winning bet at the end of any run of losses pays back every earlier loss and leaves $5 profit. The examples on this page use a $5 first bet, a $500 table maximum, a $1,000 bankroll and a +$100 target per session. They are round numbers for the arithmetic, not any casino’s rules.
| Losses in a row | Next bet | Total lost so far | Chance, European wheel | Chance, American wheel |
|---|---|---|---|---|
| 1 | $10 | $5 | 1 in 1.9 | 1 in 1.9 |
| 2 | $20 | $15 | 1 in 3.8 | 1 in 3.6 |
| 3 | $40 | $35 | 1 in 7.4 | 1 in 6.9 |
| 4 | $80 | $75 | 1 in 14.4 | 1 in 13.0 |
| 5 | $160 | $155 | 1 in 28.0 | 1 in 24.8 |
| 6 | $320 | $315 | 1 in 54.5 | 1 in 47.0 |
| 7 | $640 (over the limit) | $635 | 1 in 106.2 | 1 in 89.4 |
The ladder is short. From $5, seven losses in a row cost $635, and the eighth bet would be $640, over the $500 table maximum. The system stops there, because the player can no longer place the bet that was meant to win everything back.
Every spin on the ladder is the same bet. A red/black bet wins on 18 of 37 pockets on a European wheel, 48.65% of spins, and on 18 of 38 pockets on an American wheel, 47.37%. The zero pockets are the reason both figures sit below half.
Roulette odds for one sequence
A sequence is one climb up the ladder. It ends at the first win, +$5, or after seven losses, -$635.
| Per sequence (play until one win or seven losses) | European wheel | American wheel |
|---|---|---|
| Chance of an even-money win on one spin | 48.65% | 47.37% |
| House edge on each bet | 2.7% | 5.26% |
| Chance the sequence ends in seven losses (-$635) | 0.94% | 1.12% |
| Otherwise the sequence wins | $5 | $5 |
| Average amount bet per sequence | $37.97 | $41.04 |
| Expected result per sequence | -$1.03 | -$2.16 |
| Expected result as a share of money bet | -2.7% | -5.26% |
Seven straight losses come 1 in 106.2 sequences on a European wheel (0.94%) and 1 in 89.4 on an American wheel (1.12%). The expected result per sequence, the average over every way the sequence can end, is -$1.03 on a European wheel and -$2.16 on an American wheel. The money bet per sequence averages $37.97 and $41.04. Divided, those give -2.7% and -5.26%. That is exactly the house edge: the share of every bet the casino keeps on average, because the payout is set below the true odds.
The reason is simple. Every single bet in the ladder carries that edge. Doubling changes how much is bet after a loss, and it leaves untouched what each dollar is expected to return. So the bets in a sequence, added together, return the same share as one flat bet. The martingale system gathers the losses into rare large ones.
Sessions: many small wins, a few large losses
A session here runs sequences until it is $100 up, which takes 20 winning sequences, or until the first busted sequence. One busted sequence costs $635 of the $1,000 bankroll.
| Session: stop at +$100 or at the first seven-loss streak | European, exact | European, simulated | American, exact | American, simulated |
|---|---|---|---|---|
| Sessions that reach +$100 | 82.8% | 82.8% | 79.9% | 79.8% |
| Sessions that end in a loss | 17.2% | 17.2% | 20.1% | 20.2% |
| Average loss in a losing session | -$588.74 | -$589.39 | ||
| Average result per session | -$18.79 | -$18.58 | -$38.90 | -$39.11 |
| Result as a share of all money bet | -2.68% | -5.28% |
Worked exactly, 82.8% of sessions on a European wheel reach +$100 and 17.2% bust. On an American wheel the split is 79.9% and 20.1%. The average result per session is -$18.79 on the European wheel and -$38.9 on the American wheel. Most sessions end up, and the average is still negative: a winning session makes $100, while a busted sequence costs $635.
The simulation played every spin, 3,730,135 of them on the European wheel across 100,000 sessions, with seed 20261105. It gave 82.8% of sessions at +$100 and an average result of -$18.58. The American wheel gave 79.8% and -$39.11. The worst session in both runs lost $635 and the best won $100.
In this run the European sessions bet $69,431,965 in total, and the result was -2.68% of money bet against an exact edge of 2.7%. The American run gave -5.28% against an exact edge of 5.26%.
The bust is rare per sequence and common over many. Across 100 sequences, the chance of at least one seven-loss streak is 61.2% on a European wheel and 67.5% on an American wheel.
The same ladder on -110 sports sides
A -110 price changes the multiplier. Each stake must win back every earlier loss plus $100, so it grows 2.1 times instead of doubling.
| Bet | Stake at -110 | Total staked | Chance of losing this many in a row at 50% |
|---|---|---|---|
| 1 | $110.00 | $110.00 | 1 in 2 |
| 2 | $231.00 | $341.00 | 1 in 4 |
| 3 | $485.10 | $826.10 | 1 in 8 |
| 4 | $1,018.71 | $1,844.81 | 1 in 16 |
| 5 | $2,139.29 | $3,984.10 | 1 in 32 |
| 6 | $4,492.51 | $8,476.61 | 1 in 64 |
A $10,000 bankroll covers six bets, $8,476.61 in total. The seventh stake would be $9,434.27, and the bankroll cannot cover it after six losses.
The win rate here is an assumption: 50%, a side with no edge. At that rate six straight losses come 1 in 64 sequences (1.56%), and the expected result per sequence is -$34.01. The price explains the loss. A -110 bet needs 52.38% wins to break even, so at 50% each bet loses 4.55% on average. Doubling up changes how much is bet, as it does on the wheel, and every bet still carries that 4.55%.
If you play, set your limits before the first bet. Our guide to responsible gambling covers deposit, loss and time limits, and self-exclusion.
*Sources: our exact calculations and a simulation of 100,000 sessions per wheel (Python, seed 20261105), run on 5 November 2026; the $5 first bet, $500 table maximum, $1,000 bankroll and +$100 target are examples, not any casino’s rules.*