Roulette betting systems explained

What roulette betting systems are, and what they can't do

A betting system is a rule for sizing your next stake based on what just happened. Some raise the stake after a loss (negative progressions such as Martingale), some raise it after a win (positive progressions such as Paroli), and others spread chips across the layout in a fixed pattern. They are popular because they feel organised and because, over a short session, many of them do produce a small profit more often than not.

What they can't do is alter the chance of the ball landing in a pocket. A single-zero wheel has 37 pockets and an American wheel has 38. Every bet on the roulette table pays as though there were only 36 pockets, and that gap is the house edge. The size of your previous bet, or whether it won, has no effect on the next spin.

As Wizard of Odds' betting systems guide (opens in a new tab) puts it, systems don't beat games with a house advantage and "can't even dent it". That is the starting point for everything below: a system changes the shape of your results, not their average.

Why no roulette betting system changes the house edge

Each spin is an independent event. On a single-zero table every individual bet, whatever its size, has an expected value of minus 1/37 of the stake, or -2.70%. Add up any sequence of bets, however cleverly sized, and the expected result is minus 2.70% of the total amount you put down. A system can only move money between "more bets" and "bigger bets"; it can't create a bet with a better average.

The formula is simple: expected loss = total staked × house edge. The table below applies it. Notice that the expected loss depends only on how much you stake in total, not on the order or pattern of the stakes.

Large simulations confirm the arithmetic. In one Wizard of Odds roulette run on a double-zero wheel, a flat bettor lost 5.2668% of the money wagered and a Martingale bettor capped at a $200 bet lost 5.2688%, both in line with the 5.26% edge. The patterns looked very different from session to session, but the long-run ratio was the same.

Systems tend to raise the total amount you stake, because progressions push bets up after losses or wins. Since the cost is a percentage of total stakes, many systems cost more per hour than steady flat betting at the same starting stake.

Popular roulette betting systems compared

Here are the systems players ask about most, what each one does to your stake, and what the long-run numbers show. All of them were designed for even-money bets such as red or black, which win 18 times in 37 on a single-zero wheel.

Each system has its own page with worked examples: Martingale, reverse Martingale, Paroli, d'Alembert, Fibonacci, Labouchère and the James Bond spread. The summary column is the same for every row, because the edge is built into the payouts, not the staking.

The Martingale roulette strategy in pounds

Martingale doubles the stake after each loss, so that the first win recovers every earlier loss plus one base unit. The system is old: its family of strategies was popular in 18th-century France, as Wikipedia's Martingale article (opens in a new tab) records. On paper it looks tidy. In practice the stakes grow very quickly.

Suppose the table maximum is £500, so you can't place bet eight. A sequence then wins £5 unless seven reds in a row fail, which happens with probability (19/37)^7, about 0.94% or 1 time in 106. The expected result per sequence is £5 × 0.9906 minus £635 × 0.0094, which comes to about -£1.03. The average amount staked per sequence works out at roughly £37.97, and £1.03 is exactly 2.70% of that. The system wins most sequences and still loses the house edge on everything it bets.

Roulette odds of a losing streak on even-money bets

Progressions break on losing streaks, so it helps to know how often they come. An even-money bet on single zero loses 19 times in 37 (the 18 numbers of the other colour plus zero). Multiply that by itself for each spin in the streak. Wizard of Odds' Martingale answer (opens in a new tab) gives the eight-loss figure as 0.004835; the rest of the table is the same calculation.

A 1 in 207 chance sounds remote, but a player running many Martingale sequences across an evening is starting a fresh sequence after every win. Streaks that are rare per sequence become ordinary over hundreds of spins. The famous 1913 Monte Carlo run of 26 blacks, covered on our history of roulette page, is an extreme case, but runs of six to eight losses are a normal part of the game.

d'Alembert, Fibonacci and Labouchère: gentler progressions, same edge

These three systems raise stakes after losses more slowly than Martingale, which makes the big disasters less frequent but doesn't remove them.

d'Alembert

Add one unit after a loss and take one off after a win. In Wizard of Odds' d'Alembert simulations (opens in a new tab) on single-zero even-money bets, players reached their session goal between 89.81% and 99.26% of the time depending on the settings, yet the expected result was negative in every case and the losses matched the 2.703% edge. A high success rate and a negative average aren't a contradiction; the failures are simply much larger than the successes.

Fibonacci

Stakes follow the sequence 1, 1, 2, 3, 5, 8, 13 and so on: move one step up after a loss and two steps back after a win. Simulations give a money-won-to-money-bet ratio of -0.0270 on single zero and -0.0526 on double zero, which is the house edge to four decimal places. Ten losses in a row from a £5 unit already call for a £445 stake.

Labouchère

Write a line of numbers, bet the sum of the two ends, cross both off after a win and add the lost amount to the end after a loss. Wizard of Odds notes that it "usually results in a session win, but at the expense of huge losses when it doesn't", and its loss-to-wager ratio again matched 2.70% and 5.26%.

Reverse Martingale and Paroli: pressing wins

Positive progressions do the opposite: they raise the stake after a win and drop back after a loss. Your downside per sequence is limited to one base stake, which feels safer, but a target such as three wins in a row on red only comes off with probability (18/37)^3, about 11.5%. Most sequences end with a small loss and the occasional run pays for some of them. The edge on every bet is still 2.70%, and Wikipedia's account of the anti-Martingale says it also fails to generate a profit over time.

If you prefer this style, it simply means accepting more small losing sessions in exchange for a less violent worst case. It is a matter of taste in variance, which our volatility guide explains, not a way to improve the odds.

Spread systems: covering more numbers doesn't lower the edge

Some "systems" don't progress at all; they place a fixed mix of bets every spin, such as a large chip on 19 to 36, a six line and a chip on zero. Covering more numbers raises the chance that something wins, but each component bet carries a 2.70% edge on single zero, so the whole spread does too. On £20 a spin the average cost is 54p a spin whatever the mix. The same applies to call bets such as voisins du zéro.

A realistic roulette strategy: choose the wheel and set the budget

The levers that really change your costs are the wheel and the rules, not the staking pattern. A double-zero wheel costs 5.26% per bet, a single-zero wheel 2.70%, and a French table with La Partage cuts even-money bets to 1.35%, because half the stake comes back when zero lands. See our roulette odds page for the full table of chances.

Here is what that means for a player betting £10 a spin at an assumed 40 spins an hour: about £21.04 an hour on double zero, £10.80 on single zero and £5.40 on French even-money bets. Those are averages; any one session can land well above or below them.

1. Pick a single-zero table, and a French table with La Partage if you mostly bet red/black, odd/even or high/low.
2. Decide your session budget before you start, and treat it as the price of the entertainment.
3. Choose a flat stake small enough that the budget covers a session you'd be happy with; our budget question has worked figures.
4. Set a deposit limit and a reality check in your casino account so the plan holds when you're mid-session.
5. Stop when the budget is spent or the time is up, win or lose, and never raise stakes to win back losses.

Betting systems at UK online and live roulette tables

In Great Britain, online roulette must use outcomes that are "acceptably random" under the Gambling Commission's remote technical standards, and compensated games that adjust results to make up for past spins aren't allowed. Live tables use a physical wheel; RNG and live roulette share the same single-zero maths. Neither type remembers your last bet.

Two UK rules matter to system players. Since 17 January 2025, autoplay is banned for all online casino games, live casino included, and non-slot games must allow at least 5 seconds per game cycle, so every progression has to be placed by hand. Table limits also cap how far any progression can run; our guide to choosing table limits explains how minimums and maximums interact with stake sizes.

Where to play roulette with a sensible budget

None of our partner offers is designed for roulette. Casumo's 50% bonus up to £100 (18+, new customers, opt-in, minimum first deposit £20, wager the bonus 10x within 7 days, £5 maximum bet while it's active) comes with game restrictions, and table games are often excluded or count for less towards wagering. 10bet's 100% match up to £25 (first deposit within 7 days, 10x wagering on slots within 3 days, £1,000 maximum bonus winnings, Skrill and Neteller excluded) must be wagered on slots. Coral's bet £10 on slots, get 100 free spins offer (10p spins on selected games, 48 hours to accept, 7 days to use, no wagering on winnings, some payment types excluded) is slot-only.

If you want roulette, look at the casino's table and live lobbies for single-zero and French games, check each game's help screen for its rules, and read the bonus terms before opting in. 18+ only, and terms apply.

18+. Every casino game has a built-in house edge, so over time you should expect to lose what you stake. Set a budget before you play and stop when it’s gone: safer gambling tools and support. Free, confidential help: National Gambling Helpline 0808 8020 133.