The Labouchere betting system, also known as the cancellation system or split-Martingale, is a progressive betting strategy most commonly used in roulette. The strategy consists of players deciding on a profit goal and splitting it into multiple units in a sequence. The player then combines the first and last units of the sequence and uses it in an even-money bet. If the bet wins, these units are removed from the sequence, and the process repeats. If the bet loses, the lost stake is summed and added as the last number of the sequence, after which the process repeats again.

Like most roulette betting systems, this strategy cannot be used to increase the probability of winning or guarantee success. Instead, it manages variance to ensure that most gaming sessions succeed. However, losing sessions still happen and can be extremely costly due to the system’s progressive nature.

This guide tells you everything you need to know about the Labouchere betting system, explained in plain English. The guide focuses on roulette and roulette-based examples because it’s the most common use case for Labouchere. Besides a step-by-step guide, we’ll also discuss the risk math and strategic takeaways, giving you an in-depth understanding of the pros and cons of this strategy.