JeffBet by Matthew Gover |
Date of Publishing: 26 October 2022

5/5 - (2 votes)

Roulette Odds & Probability Explained

Roulette is a traditional casino game that can be found in every casino in the world. An understanding of the odds is essential for your quality of play. If you were to play a game of roulette for example with no knowledge of the odds you are likely to enjoy the game far less. You might be celebrating a win but have no idea how much you have won. If you have placed multiple bets how would you even know you have made a profit if you don’t understand roulette odds? Most players would also like to have some understanding of whether the bets they are placing are either longshots or in the case of a red and black bet, almost as good as 50/50. 

After this guide, things should be pretty straightforward for you. We will be explaining how the odds work on our roulette games at JeffBet as well as explain the difference between the Traditional version of the game and the American version.

What Are Roulette Odds?

Roulette’s odds inform you what your potential payout will be for a given wager. In American roulette, for instance, a straight-up bet on a single number has odds of 37 to 1 despite there being 38 possible outcomes. The payout percentage is typically displayed as a ratio to the amount wagered, while the odds are typically displayed as a percentage.

To fully understand the odds and probabilities involved in roulette, we must also examine another factor. Even though the odds of winning are 36 to 1 on a European single-zero roulette wheel and 37 to 1 on an American double-zero wheel, this does not guarantee that you will win every 36 or 37 spins. Players at the tables wish this were true, but alas, it isn’t.

In the short run, anything can happen. You could win a 50/50 bet ten times in a row or you could lose the same bet 10 times in a row. You could be crying tears of defeat during a long losing streak, or you could be strutting through the casino like a God after a run of incredible fortune. If you are unaware of the game’s probability, you can start believing that you are amazing at the game due to a lack of understanding of what is taking place.

The odds in roulette start to take form as time marches on. Though the outcomes will never be 100% accurate, they should be fairly close to what the numbers would predict. In gambling, many people suffer from short terminism. They might see 100 spins of the roulette wheel on our site and then analyse their results and come to the conclusion of great success or dismal failure. The truth is for the odds to run somewhere close to the actual probability, you likely need to place over 1000 bets.

The odds and probabilities of winning or your potential European or American roulette payouts do not change regardless if you play for one spin or a thousand. Many roulette players mistakenly believe they can win by using their logical skills to beat the odds and ignore this factor. This is called the gambler’s fallacy. If it has been red the last nine times, therefore it is less likely to be red next time. This couldn’t be further from the truth. The odds remain the same for every spin!

Roulette’s House Edge

The mathematical edge that the gambling game, and by extension, the online casino, has throughout a session of play is referred to as the “House Edge.” With this edge, the casino has a slight advantage over the player. Every casino has a house edge, but roulette has one of the smallest. If you were to bet on the toss of a coin, there would be no house edge as the outcome would either be heads or tails. In roulette, the zero makes the casino have a slight house edge as it is not included in the odds.

When playing with American double-zero wheels, the house edge is 5.26%; when playing with European single-zero wheels, the house edge is 2.70%. The casino roulette odds of losing 5.26 units for every 100 units wagered are higher on the American double-zero variant than on the European single-zero variant.

Understanding Roulette Payout

If you bet on just one number and it comes up, you’ll get 36 times your money back (£36). The full list of payouts for roulette can be found in the table below. 

BetPayoutEuropean Roulette OddsAmerican Roulette OddsAmerican Roulette House EdgeEuropean Roulette House Edge
Red and Black1:148.65%47.37%5.26%2.70%
Even and Odd1:148.65%47.37%5.26%2.70%
Low and High Numbers (1-18 / 19-36)1:148.65%47.37%5.26%2.70%
6 lines (6 Numbers)5:116.22%15.79%5.26%2.70%
Top line (5 Numbers)6:113.16%7.89%
Square (4 Numbers)8:110.81%10.53%5.26%2.70%
Street (Numbers)11:18.11%7.89%5.26%2.70%
Split (Two Numbers)17:15.41%5.26%5.26%2.70%
Straight (1 Number)35:12.70%2.63%5.26%2.70%

Within the confines of a roulette table, players can place their chips either “inside” the layout or “outside,” hence the names “inside” and “outside” bets. Below is what each of these bet types are and how they work.

Outside Bets

These wagers, also known as “even money bets,” are typically the safest ones to make because the chances of winning are far greater. 

Red, black, even, odd, or numbers 1-18, and 19-36 effectively divide the table in half for betting purposes. As the odds of winning these bets are close to 50% in both European and American roulette, the payout is also equal to 1.

The first, second, or third dozen are less likely to happen (1-12, 13-24, and 25-36). The payout for a dozen bets in European roulette is 2 to 1 and 32.43% in American roulette. This rule also applies to wagers placed in columns. 

Inside Bets

These wagers have lower odds of winning but higher potential rewards. Those wagers can be placed on single numbers or on multiple numbers together. Inside bets can come in a variety of forms.

  • A straight bet is one in which the player chooses a single number. These are the least likely outcomes, but they pay out at 35 to 1.
  • Bets that cover two numbers at once are known as “splits.” The payout for these is 17 to 1.
  • Street is any wager covering three adjacent numbers, such as 4, 5, and 6. The payout for this wager is 11-1.
  • A corner bet includes the numbers 8, 9, 11, and 12, and is also called a square bet or a quarter bet. Eight to one is the payout.
  • Bet across six numbers for a 5-1 payout on the Six Line.

Roulette Probabilities

Many people who enjoy gambling at casinos or on the Internet either don’t know how roulette probability works or don’t care. How someone decides to play is entirely up to them of course, however, playing without this knowledge is almost guaranteed to affect your long-term results.

Let’s start with the double-zero American roulette probability. The wheel is filled with 38 numbered compartments (1 through 36 plus 0 and 00). Say you decide to wager on the number 17, widely believed to be both James Bond’s favourite and the most frequently wagered upon in the game.

With 38 possible outcomes, betting on 17 means putting money on just one of those outcomes. The odds of getting a 17 are 1 in 38. If you landed on this number, your payout would be 1 in 36. This is a callback to the casino’s house edge.

European Roulette v American Roulette

American roulette includes two zeros. However, the numbers on the wheel in European roulette are arranged differently, and the double zero (00) slot is absent from this version of the game’s wheel. On a green background, you’ll find a single zero. Even though this seems like a minor distinction, it has a significant impact on the player’s overall odds once you learn the intricacies of the game.

In the European version, the house edge is 2.7%. American roulette, on the other hand, has a house edge of 5.26%, nearly double that of European roulette. What this means is that while the RTP for European roulette is 97.3%, it is only 94.74% for American roulette. Overall this would indicate that you have a very slightly improved chance of winning money if you played on a European roulette table. On our site, you will be able to find some very fun variations of the game but the odds remain the same.

Is it Possible to Improve your Chances while Playing Roulette?

You cannot change the odds of roulette or lower the house edge in any way. However, knowing the odds is crucial when placing wagers. Although there is no foolproof strategy for winning roulette bets, we at Jeffbet think that there are ways to increase your chances of success.

Always be prepared for every game: Roulette’s odds of various bets paying out vary widely. To get the most out of your real money games, research the payout percentages of various bets before you play. While some online games will reveal the odds of each bet as you play, others won’t.

Be Smart with your game selection: Knowing the odds for American and European roulette will help you make the right choice if you’re on the fence about which to play. We suggest European roulette because it has the smallest house edge.

Opt for outside bets to improve winning chances: The outside bets in roulette give you the best chance of winning if that is your only concern. These have higher payout rates and allow you to play safely by betting only the table minimum. In roulette, a low-risk strategy that gives you a good chance of winning is to place two equal outside bets, such as on black and odd. This strategy won’t significantly boost your roulette payouts, but it will help you have fun without risking a lot of money.


In the American variant, roulette betting odds on either red or black are 47.4%. With European roulette, this percentage is raised to 48.6%. You can expect to receive a payout ratio of 1:1 if you win at either version of roulette with such a bet.
Like when you play the lottery, roulette is a game of random numbers, so it is down to luck. While there are a few strategies that players may swear by, none of them guarantees to win. If you were to place bets on single numbers all of the time, you are more likely to lose with more frequency while if you placed outside bets, you are more likely to not experience such drastic losing streaks.
If lady luck is on your side, then you can win money playing roulette. With a house edge of only 2.64%, European roulette is a game that is very possible to win when you sit down for a section. As a result of the house edge, however, gambling establishments are still likely to come out on top in the long run.
Yes, random number generators (RNGs) make sure that non-live dealer games played always have random and unpredictable results.

About the Author

Author: Matthew Gover.

After graduating, Matthew began working as an English teacher abroad, initially in Spain and then Vietnam before finally coming back to the UK to settle. Matthew has always had a love for writing and an even bigger love for the igaming industry... Read More

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