We have all seen the films where the suave lead character bets on a single number at roulette and wins, only to repeat the exact same bet again and, hey presto, they win again.
Then off he goes into the sunset with a girl on his arm and a drink in his hand.
It might look good in the movies but it’s incredibly unlikely to happen in real life. Although that being said, read to the end for an unbelievable bit of James Bond/Sean Connery trivia.
To the question at hand though; what are the odds of a number coming up twice in a row in roulette? Well it actually depends on how you ask the question.
We will explain in detail below, and even take things further by showing the odds of the same number coming in up to ten times in a row.
Calculating the Odds of a Number Repeating in Roulette
There are a few things to consider here, and the first is pretty basic. Namely, are you playing European or American roulette?
Obviously European roulette has one less number on the wheel than its greedy American cousin, so the odds will be different to account for that.
The other thing to consider is what you actually mean by the question.
Using European roulette as an example, the odds of any number coming up are one in thirty seven, or 1/37, because that’s how many numbers are on the wheel. Each number has an equal chance of landing.
This means that on every single spin there is a 1/37 chance of any number coming up regardless of what happened on any previous spin, because each spin is independent and previous results have no impact on future results.
Essentially then, the odds are the same on every spin.
However, looking at it in a different way, we can calculate the statistical probability of the same specific number coming up twice in a row.
On the first spin the odds would remain at 1/37, but once that number had hit, the odds of it coming up again straight away would be different, because you are now taking a previous spin into consideration.
To work out the odds for this we would have to multiply the initial odds by themselves, or in other words, calculate 1 divided by 37 to the power of 2, written like this: 1 ÷ 37 x 1 ÷ 37 or 1/37^2.
The answer would therefore be: 1/1369.
So you have a 1 in 1369 chance of hitting the same exact number twice. That means it should statistically only happen once in every 1369 spins of the wheel. So it’s rare.
If we do the same thing for American roulette the numbers would look different:
1 ÷ 38 x 1 ÷ 38 or 1/38^2 = 1/1444
So that extra number, the 00, makes the odds of the same number coming up twice in a row longer.
How Many Times has the Same Number Come up in Roulette History?
It’s not possible to know for sure because not every game of roulette has been documented, but the longest winning streak for a single number that has been recorded is thought to be 6.
It happened in Puerto Rico at a hotel called El San Chuan, and the number 10 came up six times in a row during a game of American roulette.
The odds of that happening are mind blowing, and we have put it into perspective in the table below, showing the odds of successive same number results using both European and American roulette:
|# of Times in a Row
The odds that hit at the El San Chuan are in bold, just over 3 billion to 1!
This table also gives you a good idea at how quickly those odds climb and how increasingly unlikely it is for the exact same number to keep reoccurring, but it does happen.
Sean Connery Hits the Same Number 3 Times in a Row
We said there was some great trivia at the end of the article and here it is.
In 1963, Sean Connery, Mr James Bond himself, was playing roulette at the Casino de la Vallee in Italy, and placed a straight up wager on number 17.
Undeterred, he repeated his bet, and again he lost.
He went for it a third time, and low and behold the ball landed on number 17, recouping his losses and winning him a pretty penny too.
You might think that this is where the story ends, but (Dr) no, Connery let his bet ride and number 17 came up once more.
Unbelievably, he made the same bet again and once more it came in again, making that three successful bets on 17 in a row, and putting £27,000 in Connery’s pocket. That’s around £160,000 in today’s money.
Connery must have felt more ‘Bond’ than ever as he left the casino that night.