Where Those Letters Sit
When you first look down at a roulette table, the wheel gets most of the attention, but the felt around it carries a set of letters that confuse new players more than the numbers do. Those letters do not appear on the wheel. They live only on the betting layout, and they are shorthand for the outside bets that sit along the edge of the number grid.
The most common letters you will see are 1st 12, 2nd 12, 3rd 12, 1-18, 19-36, EVEN, ODD, and the red and black diamonds. On many layouts, particularly European-style tables, the dozens are printed as P12, M12, and D12, where P stands for premiere, M for milieu, and D for derniere. Those are French terms for first, middle, and last. On an American-style layout you are more likely to see the plain English 1st 12, 2nd 12, and 3rd 12. Both sets of letters point to the same three wagers.
Below the dozens you will usually find three blank boxes or squares, often unlabelled. These are the column bets, and they pay 2 to 1. The letters on the table are therefore not a code to be cracked. They are simply the labels for the group bets that sit outside the numbered grid, and learning them is the first step to understanding how a round is played.
The Layout and the Wheel Are Two Different Things
A common misreading is to assume that the letters on the felt correspond to something spinning on the wheel. They do not. The wheel has 37 pockets on a European single-zero game and 38 on an American double-zero game, numbered 0 through 36. The layout is a separate surface where you place chips, and it arranges those same numbers in a grid with the outside betting areas wrapped around it.
The letters mark areas where a bet covers a group of numbers rather than a single pocket. A chip placed on 1st 12 covers every number from 1 through 12. A chip placed on the column box at the foot of a column covers all twelve numbers in that vertical column. Because these bets cover many numbers at once, they pay less than a straight-up bet on a single number, but they also win more often. The letters are the table's way of telling you which group a chip belongs to when it sits in one of those shared areas.
What Each Lettered Area Means
The outside bets on a roulette layout break down into a few families. The dozens and columns are the twelve-number bets. The even-money bets cover eighteen numbers each, and the letters for those are usually printed as words or single characters rather than abbreviations. Here is how the main lettered areas compare.
| Marking on the layout | What it means | Numbers covered | Standard payout |
|---|---|---|---|
| 1st 12 or P12 | First dozen | 1 through 12 | 2 to 1 |
| 2nd 12 or M12 | Second dozen | 13 through 24 | 2 to 1 |
| 3rd 12 or D12 | Third dozen | 25 through 36 | 2 to 1 |
| Column box (often blank) | Column bet | All 12 numbers in that column | 2 to 1 |
| 1-18 / 19-36 | Low or high half | 18 numbers | 1 to 1 |
| EVEN / ODD | Even or odd numbers | 18 numbers | 1 to 1 |
| Red / black diamond | Colour bet | 18 numbers | 1 to 1 |
The zero is the exception that matters. On a European wheel, the single zero is not covered by any of the even-money bets, the dozens, or the columns. When the ball lands in zero, those outside bets lose on most layouts, though some tables use a rule that returns half the stake on even-money bets. On an American wheel, both the zero and the double zero sit outside those groups. That is why the American layout carries a higher house edge than the European one: the extra pocket is added without adding any extra coverage to the outside bets.
How a Round Moves From Buy-In to Settlement
A roulette round is faster than most new players expect, and the letters on the felt only matter because of where they sit in that sequence. The round begins when you buy in at the table and receive coloured chips that are unique to you at that table. Those chips have no denomination printed on them; the dealer assigns their value when you buy in, and they are only valid at that table until you cash them back for standard casino chips.
Once the dealer opens betting, you place chips on the layout. A straight-up bet goes directly on a number. A split goes on the line between two numbers. A street covers three numbers, a corner four, and a six-line covers six. The lettered areas are where you place the group bets: on the 1st 12 box, on the column box at the foot of a column, or on the red diamond. You can mix inside and outside bets in the same round.
The dealer then spins the wheel and releases the ball in the opposite direction. When the ball settles, the dealer marks the winning number, clears the losing chips, and pays the winners. Outside bets are paid first, then inside bets. A winning dozen or column bet pays 2 to 1, meaning you receive two units of profit for every one unit staked, plus your original stake back. A winning even-money bet pays 1 to 1. The letters on the layout are therefore not decorative; they are the exact places where the dealer looks to settle those group bets.
The Decision Points That Change Your Edge
Roulette is often described as a game with no decisions after the bet is placed, but that is only half true. You cannot change the spin, and no betting pattern alters the built-in edge, but you do decide which bets to place, and those bets carry materially different edges on the same wheel. The letters on the table mark some of the better choices on a European layout, but the difference between bet types is real and worth understanding before you sit down.
On a European single-zero wheel, the house edge on a straight-up number, a split, a street, a corner, a six-line, a dozen, or a column is the same: the zero pocket is the house's edge, and it applies equally to all of those bets. The even-money bets carry that same edge on a standard layout. On an American wheel, the double zero adds a second house pocket, and every bet on the layout carries a higher edge than its European counterpart. The letters do not change that; they only mark where the bets sit.
The one bet that stands apart is the five-number bet on an American layout, which covers 0, 00, 1, 2, and 3. It pays 6 to 1, but because it covers five numbers on a 38-pocket wheel, it carries a higher edge than any other bet on the table. No letter marks it, and it is easy to miss. If you are comparing bets, the useful comparison is not between the dozen and the column, which share the same edge on a given wheel, but between the European and American layouts, and between the standard bets and that five-number exception.
What the Letters Cannot Tell You
The letters on a roulette table are a labelling system, not a strategy system. They do not signal which bet is due, which dozen is hot, or which column has been hitting. A roulette wheel has no memory, and each spin is independent of the last. The letters simply mark the areas where group bets are placed, and the payouts for those areas are fixed by the table rules.
If you want to know the exact payouts and rules for a specific table, the layout itself is the document to read. The minimum and maximum stakes are printed on a plaque at the table. The payout for each bet is printed on the felt or shown on the electronic display. The rule about what happens to even-money bets when zero lands is printed on the layout or stated by the dealer. Those are the details that change from table to table, and the letters are only the first layer of that information.
FAQ
Why do some roulette tables use P12, M12, and D12 instead of 1st 12, 2nd 12, and 3rd 12?
Those are French abbreviations carried over from the game's European origins. P, M, and D stand for premiere, milieu, and derniere, meaning first, middle, and last. They mark the same three dozen bets as the English labels, and the payout and coverage are identical. The choice of lettering is a table-design convention, not a rule difference.
Do the letters on the table affect the house edge?
No. The letters are labels for betting areas, and they do not change the mathematics of any bet. The house edge on a given roulette bet is set by the wheel type, specifically whether it has a single zero or a double zero, not by how the layout is printed. A dozen bet carries the same edge whether the felt says 1st 12 or P12.
What is the unmarked box at the bottom of each column?
That is the column bet. It is often left blank or marked only with a small symbol because the column itself is the label. A chip placed there covers all twelve numbers in that vertical column and pays 2 to 1. The column bet is a separate wager from the dozens, even though both cover twelve numbers.
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