Roulette

Roulette is probably the casino’s most iconic table game. The spinning wheel is recognized the world over as a symbol of games of chance. In Las Vegas the wheels have 38 spaces, called “pockets”: 18 reds, 18 blacks, and two green. The green pockets are zero and double-zero.

Ask the croupier to place your bet on the game layout, and then watch him (or her) spin the wheel. The wheel will go in one direction and the small white marble in the other. Bets can be made up to the moment when the ball begins its descent from the rim of the wheel towards the pockets. Then the croupier will pay off the winners and collect from the losers.

Betting options are either “inside” or “outside.” The “inside” bets are on a specific number or series of numbers. The “outside” bets are for combinations, like “odd,” “even,” “red,” “black,” etc. The payoffs are higher for the inside bets, but the odds of winning are lower. For outside bets, the chances of winning are much better, but the payoffs are smaller.

The house advantage will vary with the type of bet made. It is fairly obvious with an “odd” bet. The odds that the ball will land in an odd-numbered pocket are 18 out of 38, or 47.37%. The odds of losing are thus 52.63%. But the bet pays only at 1 for 1, implying a 50% risk. When the player runs a greater risk of losing than he gets paid for winning, the advantage is with the house. How much? It is a house edge of about -5.26%. (The formula is the sum of all payoffs x their probabilities, expressed in percentage terms. In the case of a bet on one pocket, the calculation is: payoff for losing (-1), times chance of losing (37/38), plus payoff for winning (35) times chance of winning (1/38). In percentage terms, this comes to -5.26%. What is minus for the player is a plus for the house.

Roulette Basics

American Roulette employs a wheel with thirty-six numbered slots, plus a “0” slot and a “00” slot. With the exception of the zero slots, each number is either red or black. The numbers are arranged in alternating pairs of even numbers and then odd numbers.

The dealer is called a “croupier.” The croupier spins the wheel one way, and then rolls the ball around the outside perimeter of the wheel in the other way, against the spin of the wheel. Eventually, as the wheel slowly comes to a stop, gravity causes the ball to come off the edge and settle into a slot. Bets can be placed at any time before the ball starts its descent from the outside rail of the wheel. Once bets are placed they can only be changed through the courtesy of the croupier, if there is still time. Do not touch the chips yourself once they are on the table, and never touch anyone else’s chips. Some visitors to the casino break this rule, and sometimes it is even tolerated, but it is considered extremely bad form. The better practice is to know in advance what the correct bet is going to be, and then do not change your mind. The croupier is trained to know whose chips are on which spot, so if there is ever a doubt as to who bet what, the croupier will settle it. This is another good reason to have the croupier place bets for you instead of trying to do it for yourself.

The croupier collects the losing bets and pays off the winning bets according to where the chips had been placed on the roulette layout, a felt cover over the top surface of the roulette table.

The matrix that comprises the roulette layout is fundamentally a table with three columns of twelve numbers each, corresponding to the numbers on the roulette wheel other than the zeros. Around this array are additional areas for making other sorts of betting choices and combinations. The figure is a schematic of a roulette layout.

A gamer is allowed to bet on any and every possible square on the layout. Betting is accomplished by placing the chip (or chips in a single pile) in the desired location. It is not considered courteous to reach across the table (which could alter the bets) or other people, so if it is a stretch, give the chips to the croupier, who will place them for you.

The betting options are as follows. There are two categories, “Inside Bets” and “Outside Bets.” “Inside Bets” are in the central part of the layout; that is on any number between 1 and 36. There are five varieties of inside bets, as follows:

• A Straight Bet would be that a specific number will come up. If the ball lands on that number, the inside bet wins, and pays 35 to 1.
• A Split Bet is betting that one of any two adjacent numbers on the layout will win. The chip is placed on the line that separates the two numbers. This Bet, if it wins, pays 17 to 1.
• Street Bet (also called three number bet or trio bet) is on one number out of any three in a particular row of the layout. The chip is placed on the outside line of the row in question. It pays 11 to 1.
• Corner Bet (also called a four number bet or a square bet) is on any four squares that share a common corner on the layout. Place the chip in the middle of the four, at their common intersection. Corner bets pay 8:1.
• Five Number Bet is that one of the zeros or 1, 2 or 3 will come up. The chip goes over the line that divides the 0 and the 1. It pays 6 to 1.
• Six Line Bet is like a street bet, but on any number in two streets that touch each other. It goes on the outside line and common corner of the rows in question. Six line bets pay 5 to 1.
  Outside Bets are made by category, and the chip is placed in the appropriate field to the left, or bottom of the layout, depending on which way the layout is printed. The five categories are:
• Red or Black. To bet on one or the other color, place the chip in the field that corresponds to the color. (Zeros, being green, do not count.) The payoff is 1 to 1.
• Even or Odd. To bet on even or odd, place the chip in the field corresponding to that designation. (Zeros do not count.) The payoff is 1 to 1.
• Low or High. To bet the number will either be between 1 and 18 or between 19 and 36, place the chip in the field corresponding to that choice. Zeros do not count. The payoff is 1 to 1.
• Dozen Bet is that the number will be in the first 12 numbers, the second 12 numbers or the third 12 numbers. Place the chip in the field corresponding to the range desired. The payoff is 2 to 1.
• Column Bet is that a number in a given column will come up. The fields for column bets are at the base of each column. The payoff is 2:1.

Special Roulette Rules

The casino always has the same edge with the exception of some casinos offering special rule variations if the ball ends up on zero for bet types Red or Black, Odd or Even and Low or High when the ball lands on zero:

The In Prisonrule takes effect when the ball stops on zero during Red or Black, Odd or Even and Low or High bets. The bets are not collected by the croupier, but stay on the table. The players will then have the opportunity to win their original bet back - if they win in this second round, they get their original bet back but no extra $. If the ball lands on zero again, the bets stay in prison and the cycle repeats itself. This rule reduces the casino's edge to 1.35% - which is obviously a boon for players.

La Partage rule takes effect when the ball stops on zero for Red or Black, Odd or Even and Low or High bets. The bets are not be fully collected by the croupier, rather only half of the players bets are collected while the rest is returned. Much like the In Prison rule, the La Partage reduces the casino's edge to 1.35%.

Roulette Odds

In case it matters, the math concerning the disadvantage of the player in roulette is fairly easy. The odds of having a ball go in a specific slot are 37 to 1 (1 chance out of 38, or 2.63%), but the payoff is 35 to 1. The edge is calculated by multiplying the “real probability” by the value of the payoff (36 bets in this example) minus 1.0. Amazingly, the negative edge is the same for all the bets listed above, save for one. The table below lists the results.