The best way to play roulette, according to the maths

A European wheel has 37 pockets and pays 35:1 on a number. An American wheel has 38 and pays the same 35:1. That extra pocket is the whole difference: 2.70% house edge against 5.26%. Over an hour at £5 a spin and 60 spins, that is roughly £8 against £16 in expected loss, for an identical game.

French tables go one better. With La Partage, an even-money bet that loses to zero gets half the stake back, which cuts the edge on red, black, odd, even, high and low to 1.35%. If the lobby has a French table and you bet outside, there is no reason to sit anywhere else.

Every bet on a single-zero wheel has the same house edge. A straight-up at 35:1 and a bet on red at 1:1 both cost 2.70% of the stake on average. The difference is variance: red pays small and often, a number pays big and rarely. Neither is a better deal. Pick by how you want the session to feel, not by which "has better odds". The page on best bets goes through this in detail.

The main reason people lose more than they meant to is not the house edge. It is a stake that was too big for the money they brought. A £100 bankroll at £5 on red survives most sessions of 100 spins; the same £100 at £5 on a single number is gone in a majority of them before the 100th spin, even though the expected loss is identical. The bankroll page gives the figures.

Expected loss is stake times spins times edge. You control two of the three. A hundred spins at £2 costs about £5.40 on average; the same money spread over 300 spins costs £16.20. Decide the number of spins before you start and stop there, up or down. It is the only rule on this site that changes the outcome, because it changes the amount you put through the table.

Martingale, Fibonacci, D'Alembert, Labouchere and the rest rearrange the sequence of stakes. Some make small wins frequent and a rare loss huge; some do the reverse. None of them changes the 2.70%. The strategies page explains each one honestly, including what each does well, because some of them are perfectly reasonable ways to structure a session once you know the price.

Betting the American wheel. Chasing a loss with a bigger stake than planned. Treating the history board as information. Taking a bonus that excludes roulette. Playing a multiplier table for numbers without noticing the 29:1. The mistakes page lists them with what each costs.

Single-zero wheel, French if possible. Stakes at 1% to 2% of the bankroll for outside bets, smaller for numbers. A spin count fixed in advance. No system that escalates after losses beyond what you would stake anyway. Leave when the count is reached. That is the best way to play roulette. It will not make you a winner over time; nothing does. It will make the game cost what you decided it should cost.