Flat betting roulette strategy tested: 10,000 simulated sessions on red
Does flat betting work in roulette? Not against the house edge, which no staking plan changes. Over 10,000 simulated sessions of Flat on red on a European wheel, the average result was -$342.36 a session, against an exact expected loss of $337.84; 25.9% of sessions finished ahead and 0.0% went bust.
The baseline: the same $25 on red every spin. 10,000 sessions of 500 spins, seed 2026. Tags: flat, baseline
mean -$342.36 ± $11.14 per session · P(ahead) 25.9% · bust 0.0%
The numbers on this page come from a real run of 10,000 sessions of up to 500 spins, $5,000 bankroll, $25 unit, European wheel, saved in the spinner gallery. They are exactly what spinner’s Analyze screen shows for it, with 95% intervals.
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How the stakes move
One unit on red every spin. The baseline every other system is compared with.
Every spin the same bet, whatever happened before: 1 unit ($25) on red, pays 1 to 1.
There is no progression: the stake never changes, so this is the baseline that every progression is measured against.
The simulation
- Wheel
- European (single zero, 37 pockets)
- Bankroll per session
- $5,000
- Unit (base bet)
- $25
- Spins per session (at most)
- 500
- Sessions simulated
- 10,000
- Pace
- 40 spins an hour
- Table maximum (outside bets)
- $5,000
- Seed
- 2026
Results
| Measure | Value | 95% interval |
|---|---|---|
| Mean net result per session | -$342.36-$353.50 to -$331.22 | -$353.50 to -$331.22 |
| Median net result per session | -$350-$350 to -$350 | -$350 to -$350 |
| 10th / 90th percentile of the net result | -$1,050 / +$400 | |
| Best / worst session | +$1,550 / -$2,550 | |
| Spread (SD) per session | $568.58 | |
| Chance of finishing ahead | 25.9%25.1% to 26.8% | 25.1% to 26.8% |
| Chance of going bust (losing the whole bankroll) | 0.0%0.0% to 0.0% | 0.0% to 0.0% |
| Chance of playing all 500 spins | 100.0%100.0% to 100.0% | 100.0% to 100.0% |
| Expected loss per sessionexact, from the odds of every bet placed | $337.84 | |
| Realized loss per session | $342.36$331.22 to $353.50 | $331.22 to $353.50 |
| Expected loss per hourat 40 spins an hour | $27.03 | |
| House edge: realized vs exactloss as a share of everything wagered | 2.7% vs 2.7%2.7% to 2.8% | 2.7% to 2.8% |
| Mean amount wagered per session | $12,500 | |
| Run luck (z)how far the whole run is from the odds; within ±2 is ordinary | -0.81 |
Risk: drawdowns and bet size
| Measure | Value | 95% interval |
|---|---|---|
| Mean max drawdown (largest fall from a peak) | $839.54$832.59 to $846.48 | $832.59 to $846.48 |
| Median max drawdown | $775$775 to $775 | $775 to $775 |
| 90th / 99th percentile drawdown | $1,325 / $1,875 | |
| Chance of a drawdown of at least half the bankroll ($2,500) | 0.0%0.0% to 0.1% | 0.0% to 0.1% |
| Mean largest amount on the table | $25$25 to $25 | $25 to $25 |
| 99th percentile largest amount on the table | $25 | |
| Largest amount on the table in any session | $25 | |
| Chance of reaching the table maximum ($5,000) | 0.0%0.0% to 0.0% | 0.0% to 0.0% |
| Mean session lengthmore than half of the sessions played every spin | 500 spins |
Why no progression changes the house edge
Every roulette bet pays a little less than its true odds, because of the zero. On the European wheel used here every bet carries the same edge: 2.7% of each dollar wagered, in every run on this site, whatever the system. A betting system changes only how much you bet and when. Each spin is independent of the ones before it, so no sequence of stakes can change the edge: the expected loss is always the edge times the total amount wagered. In this run an average session wagered $12,500 in total, and the realized loss came to 2.7% of everything wagered, against the exact 2.7%.
What a system does change is the size of the bets, and with it the total wagered and the shape of the results. Raising the stake after a loss puts more money through the wheel, so the expected loss grows with it, and the risk piles up in the long losing streaks that the progression cannot afford. Compare the amount wagered, the bust rate and the drawdowns of each system in the table on the strategies page.