The gambler’s fallacy is easy to recognise on paper and hard to resist in the moment. Here is where it comes from and what to do instead.
The streak at Monte Carlo.
In 1913, at the Monte Carlo Casino, a roulette ball landed on black 26 times in a row. Gamblers became convinced that red had to come soon and lost millions of francs betting against black. The odds of either colour repeating 26 times on a single-zero wheel are around 1 in 68.4 million. The streak was very rare, but it broke no rules of chance.
The mistake.
The gambler’s fallacy is the belief that an independent outcome that has happened less often than expected is now more likely. A roulette wheel has no memory. A single-zero wheel has 18 red pockets out of 37, so red has about a 48.6% chance on every spin. Before the 27th spin, the chance of red was exactly what it had been before the first.
Why it feels true.
Over huge numbers of plays, results do settle close to the expected proportions, so it is tempting to think a short run has to be balanced out. But later results dilute a streak. They do not correct it.
Say a coin lands heads 10 times in a row, and the next 1,000 tosses split exactly evenly. Heads are still ahead by 10, yet their share has fallen from 100% to about 50.5%. Nothing had to “catch up”.
The same mistake on slots.
Fully random games, in the UK Gambling Commission’s words, “rely purely on the statistical chance of a random event offering a win”. A run of losses on one does not make the next spin any more generous.
There is one honest caveat. The Commission explains that “compensated” machines can “slightly vary the odds” based on recent payouts. Those adjustments play out over tens or hundreds of thousands of games, and a player cannot see them, so they give you no practical way to predict the next result.
What to do instead.
- Decide your limit before you start, and stop when you reach it.
- Treat a streak as no information about what comes next.
- Notice when you are playing to win back losses. Chasing losses is a warning sign.
If gambling has stopped being fun, free and confidential help is available.
Sources
Checked on 4 November 2026.