Good and Bad Strategies for Winning at Roulette

Roulette Wheel and Excited Woman Grabbing Chips From a Roulette Table

Roulette, like most other casino games, isn’t a game where you can realistically expect to get a mathematical edge over the house.

In a sense, this means that all roulette strategies are equally worthless.

But, I’m writing a series of blog posts about good and bad strategies for various casino games, and roulette is a mainstay, so I can’t leave it out.

Most of what I’m going to look at in this post involves analyzing how to avoid the worst bets at the roulette table so that you’re at least dealing with a respectably low house edge.

Understanding the House Edge in Roulette

Playing roulette for real money is easy. You have a wheel with 38 numbers on it. 18 of them are black, 18 of them are red, and two of them are green. The two green numbers are 0 and 00, so they don’t count as high/low or even/odd, either.

If you guessed that the green 0 and the 00 are the reason the casino has a mathematical edge over the player, you’re in the front of the class.

All the bets in roulette would be break-even propositions If you remove the two green numbers from the wheel.

Here’s why:

Suppose you bet on every single number on the roulette wheel. You’d be guaranteed a win because you’ve covered all the numbers.

But you’d lose money.

The payout for a single number bet in roulette is 35 to 1, so you’d win 35 units on the bet you won.

But you’d lose 37 units on the 37 losing numbers, for a net loss of two units.

More About the House Edge in Roulette

It wouldn’t matter if you chose a different combination of bets, either. You could bet on red, bet on black, and place a single bet on each of the green numbers. You’d still see a net loss no matter where the ball landed.

If you bet on black and win, you lose the bets you had on red and the bets you had on each of the green numbers.

If you bet on red and win, you lose the bets you have on black and the bets you had on each of the green numbers.

If you bet on green and win, you still lose the bets you had on black and red and on the other green 0.

Repeat this often enough, and eventually, you’ll lose all your money.

The variation of roulette that I’ve been using for this example is called “American roulette.”

But it’s not the only variation of roulette in the world.

Finding and Playing on Single Zero Roulette Wheels Is a Good Roulette Strategy

The American roulette wheel has two green numbers, but European roulette only has a single green number. This lowers the house edge.

That number, by the way, is always expressed as a percentage, and it’s an estimate of how much you’re going to lose on each bet.

In American roulette – the wheel has two green numbers. Those, in a sense, represent the house edge, which is 5.26%.

Closeup of a Casino Roulette Wheel

Every time you bet $100 on a roulette spin, the house expects to win an average of $5.26.

That’s an average over time, though. You obviously can’t lose $5.26 on a single bet, but when you average out all the wins and losses, that’s the number you’ll wind up with if you get a huge number of bets.

In the short run, anything can happen, but in the long term, the Law of Large Numbers will ensure that your results start to resemble the mathematical expectation.

So, if you can find a roulette game that only has a single zero on it, the house edge is only 2.70% instead of 5.26%.

That cuts the amount you expect to lose almost in half, so you can have twice as much fun for the same money.

Also, with a lower house edge, you have a better likelihood of going home a winner.

Using Betting Systems Is a Bad Roulette Strategy

A roulette betting system is a set of rules for raising and lowering the size of your bets during a game in an attempt to overcome the odds. These betting systems usually rely on predicting what’s going to happen on the next spin based on what happened on the most recent spin.

For example, the Martingale System assumes that after a loss (or multiple losses), your probability of losing again goes down.

This seems to make sense at first. After all, it’s more unlikely that you’ll lose eight times in a row than it is that you’ll twice in a row.

The problem is that the roulette wheel has no memory. Every spin of the wheel is an independent event.

And you’re not placing a bet on whether the ball is going to land on a losing spot eight times in a row. You’re betting that the ball is going to land on a losing spot on your next spin.

A Specific Example of a Bad Roulette Betting System

The classic example of a roulette betting system is the Martingale System. It’s not the worst gambling strategy in the world. One of the pros of the system is that it’s dead easy to figure out and use. All you have to do is double the size of your next bet when you’ve lost the previous bet.

For example, if you bet $10 on black and lose, you bet $20 on the next spin. If that spin wins, you win back the $10 you lost on the previous spin along with a $10 profit.

If you lose twice in a row, you double your bets twice in a row, too. Now you bet $10, $20, and $40.

Again, if you win the next bet in the sequence, you win back your previous losses along with a profit equal to the amount of your initial wager.

This strategy seems foolproof, and it would be if you had an infinite bankroll and no betting limits.

But you don’t have an infinite bankroll. You have a finite amount of money you can risk at the roulette table.

Also, casinos have betting limits. The most common betting limits I see for roulette tables are a minimum bet of $5 and a maximum bet of $500.

Since you’re doubling the size of the bet repeatedly, it doesn’t take long before the next bet in the progression is too big for you to place.

Here’s an example progression:

  1. $5
  2. $10
  3. $20
  4. $40
  5. $80
  6. $160
  7. $320
  8. $640

At most casinos, you won’t be able to place the 8th bet.

Of course, you probably think a losing streak of seven bets in a row is almost impossible with an even money bet at the roulette table.

But it happens more often than you think. At an average casino, you’ll see at least one losing streak like this at least once a day.

The other drawback to this system is that it guarantees a lot of small wins. After each progression, no matter how much you wager, the most you can expect to profit is the amount of your initial bet.

Vegas Casino Online Roulette Table Game

The amount you risk, though, goes up to staggering amounts rapidly.

Much of the time, the Martingale System will work. If you limit your playing session to about an hour, you have a close to 80% probability of walking away from the table with a winning session.

But it will be a small profit.

The other 20% of the time, you’ll have a large enough losing session to wipe out all the previous profits from the small winning sessions.

Clocking Roulette Wheels and Looking for Biases

The house edge in roulette assumes that you’re dealing with a random game. It assumes that every number comes up 1/38 of the time.

If you found a roulette table where some of the numbers come up more often than that, you could theoretically find yourself in a profitable situation.

If you found a wheel that was imperfect and had a bias toward a set of numbers that came up 1/34 of the time, you’d have the edge over the casino. Those numbers would still have a 35 to 1 payout, so you’d profit regularly just by betting those numbers.

How would you discover a roulette wheel with such a bias?

You will just clock the actual results at that wheel for a few hundred spins to see if any of the numbers come up more often than they statistically should.

The trick to clocking a roulette wheel is getting enough data. Remember, in the short run, anything can happen with one of these random casino games. It’s only when you get into the long term that you can make any assumptions with any kind of statistical validity.

Imagine this scenario, though:

You clock a roulette wheel for hours.

And it turns out that the wheel has no bias.

Now you start over with another wheel, and after several hours of clocking results, you discover a bias.

You go home to get some rest before doing some serious gambling on that wheel.

But while you’re sleeping, the casino replaces the wheel you were clocking yesterday with a new wheel.

Clocking a roulette wheel and looking for a bias is a legitimate advantage strategy for roulette, but it’s not practical. Most people don’t have the time to invest in clocking a roulette wheel.

And even if they do, they’re not guaranteed to find a biased wheel. Modern casinos use modern, state-of-the-art equipment, and it’s usually pretty random.


Let’s be honest. There are no really good strategies for playing roulette.

Betting systems don’t work.

Finding a biased roulette wheel is a longshot at best. It’s impractical, too.

Your best bet is to find a roulette wheel with a single zero and play it instead of the wheel with the two zeros.

But all that does is let you lose your money more slowly.

If you want a real winning strategy for roulette, here’s my best idea:

Learn how to play blackjack or poker instead.