Terms like odds, RTP, and house edge can feel technical at first, but they explain how roulette works and why results unfold the way they do. A little clarity goes a long way when choosing how and where to play.
Different wheels and bets change the numbers behind the game. Once you understand how payouts relate to probability, the picture becomes much clearer.
This guide breaks down roulette odds and RTP, shows how wheel types affect returns, explains why payouts do not match true probability, and uses examples to tie it all together. It also highlights key myths and ends with practical pointers on choosing a table that suits your approach.
How Roulette Odds, RTP, and House Edge Work Together
Roulette is built on three connected ideas: odds, Return to Player, and house edge. Together, they describe how often outcomes occur, how much is paid back over time, and what the casino keeps on average.
Odds show the chance of a particular result, such as a single number, red or black, or a dozen. They depend on how many pockets are on the wheel.
Return to Player (RTP) is a theoretical percentage that indicates how much of all wagers the game is designed to pay back to players, on average, over a long period. An RTP of 97.3% means that, across a very large number of spins, the game returns about £97.30 for each £100 staked. Actual sessions can be higher or lower, because RTP is a long-term average.
House edge is what remains after RTP. It is simply 100% minus the RTP. If a wheel returns 97.3% over time, the house edge is 2.7%.
With the key terms in place, the next question is how the wheel itself influences those numbers.
Impact of Single-Zero vs Double-Zero Wheels on Player Returns
Roulette wheels come in two main forms. A single-zero wheel has one green 0 and 37 pockets in total, while a double-zero wheel adds 00 for 38 pockets. That extra pocket reduces the chance of any given bet landing.
Because of this, single-zero roulette typically has an RTP of 97.3% and a house edge of 2.7%. Double-zero roulette usually sits at about 94.74% RTP, which is a 5.26% house edge. Over time, that difference is significant.
If a choice is available, many players prefer single-zero tables because they retain more of their stakes over the long run. The type of wheel sets the baseline, and the bets placed sit on top of that.
Roulette Bets Explained: Payouts and Probabilities
Roulette includes a mix of bets that cover different sets of numbers. The more numbers a bet covers, the higher its chance of success and the lower its payout. The fewer numbers it covers, the lower the chance and the higher the payout.
Straight-Up Bets
A straight-up bet is a wager on one specific number. If it lands, the payout is 35 to 1.
On a single-zero wheel, the chance is 1 in 37, about 2.70%. On a double-zero wheel, it is 1 in 38, about 2.63%.
Even-Money Bets
Even-money bets cover large groups, such as red or black, odd or even, or high 19 to 36 and low 1 to 18. They pay 1 to 1.
On a single-zero wheel, these bets win 18 times out of 37 on average, about 48.65%. On a double-zero wheel, it is 18 out of 38, about 47.37%. The zero pockets are what prevent these bets from being truly 50-50.
Column and Dozen Bets
Column and dozen bets cover 12 numbers at once. Dozens are 1 to 12, 13 to 24, and 25 to 36. Column bets cover the vertical columns on the layout. Both pay 2 to 1.
On a single-zero wheel, these bets win 12 times out of 37, about 32.43%. On a double-zero wheel, it is 12 out of 38, about 31.58%.
Knowing the basic chances sets up the next idea neatly. If the probabilities are clear, why do the payouts not match them exactly?
Why Roulette Payouts Don’t Match True Probability
Roulette payouts are fixed by the rules, but they are set slightly below true probability would suggest. That gap creates the house edge.
Take a straight-up bet on a single-zero wheel. The true chance is 1 in 37, so a probability-matched payout would be 36 to 1. The game pays 35 to 1 instead, which leaves one unit of expected value for the house across many spins.
Even-money bets show the same principle in a different way. They pay 1 to 1, but they do not win half the time because the zero pockets are neither red nor black, neither odd nor even. That small shortfall, repeated over many spins, is the edge.
The key point is that the edge is built into the pay table. Betting systems and patterns cannot remove it, and outcomes remain independent from one spin to the next.
Here is how these elements connect to the published RTP figures.
Example: Calculating RTP for a Common Roulette Bet
Consider a single-zero wheel and a straight-up bet. There are 37 pockets in total. Over 37 equal £1 wagers that cover every number once, one bet would return £35 in winnings plus the £1 stake, a total of £36, and the other 36 would return nothing.
Across the series, £37 has been staked and £36 has been returned. That is £36 divided by £37, which equals 0.973, or 97.3% RTP. The remaining 2.7% is the house edge.
This is the mechanism behind the commonly quoted 97.3% figure for single-zero roulette. It also shows why returns can drift around that average in short sessions.
What RTP Does and Does Not Represent in Real Play
RTP is a long-run measure that smooths out the highs and lows of individual sessions. A wheel listed at 97.3% RTP is designed to return £97.30 per £100 wagered when measured over a very large number of spins.
In real play, results are not obligated to match that figure in the short term. A single session might end well above or below the theoretical average. RTP is best treated as context for the game’s design, not a forecast of what any one person will receive.
This difference between statistical averages and session-by-session outcomes often leads to misunderstandings, which brings us to a few common myths.
Common Myths About Roulette Odds and RTP
Previous spins do not influence future ones. If several reds have appeared, the chance of red on the next spin is still the same as it was before, given the wheel type. Each spin is independent.
RTP is not a promise for an individual. It describes the long-term return across all play, not a target that a single player will reach after a set number of spins.
No staking method alters the underlying odds. Systems that raise or lower stakes cannot change the pay table or the chance of each outcome.
Not all wheels are equal. A double-zero wheel has a lower RTP than a single-zero wheel because of the extra pocket.
With the foundations clear, the final piece is using this information to pick a table that fits your approach.
How to Choose a Roulette Table Using Odds and RTP
Choosing a table often starts with the wheel. Single-zero tables generally offer a higher RTP than double-zero tables, which means less is kept by the house over time. If available, some versions include rules such as La Partage or En Prison that apply to even-money bets. When the ball lands on zero, these rules can return half the stake or hold it for the next spin, which reduces the house edge and can lift the effective RTP for those bets to around 98.65%.
It is also worth checking the table rules and limits. The same RTP can feel different depending on minimum and maximum stakes, the pace of play, and whether the layout and interface make it easy to place the bets you prefer.
Look at the numbers and pick the setup that suits your budget and tolerance for swings. Single-zero wheels with player-friendly rules are usually the most appealing from a statistical point of view.
If you choose to play, set personal limits that fit your circumstances and never stake more than you can afford to lose. If gambling starts to affect your well-being or finances, seek support early. Independent organisations such as GamCare and GambleAware provide free, confidential help.
If you are comparing options on our site, check the RTP and rule notes listed with each game. A few careful choices at the start make for a clearer, more informed experience at the wheel.
**The information provided in this blog is intended for educational purposes and should not be construed as betting advice or a guarantee of success. Always gamble responsibly.