A column bet is an outside roulette wager covering 12 numbers arranged in one of the three vertical columns on the table layout. A winning column normally pays 2 to 1. Zero, double zero, and triple zero are not included in any standard column.
The word column describes the printed layout, not the order of pockets on the wheel. That distinction explains most of the confusion around the bet.
The three columns are fixed number groups
Read the roulette grid from left to right. Each row contains three numbers, and each number belongs to the column directly beneath it.
| Column | Numbers covered |
|---|---|
| First column | 1, 4, 7, 10, 13, 16, 19, 22, 25, 28, 31, 34 |
| Second column | 2, 5, 8, 11, 14, 17, 20, 23, 26, 29, 32, 35 |
| Third column | 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36 |
The wager is placed in one of the three boxes marked 2 to 1 at the end of the number grid. It does not matter where the chip sits inside the box as long as the selected column is unambiguous before the dealer closes betting.
A dozen bet also covers 12 numbers, but the grouping is consecutive: 1–12, 13–24, or 25–36. The payout and ordinary house edge are the same because the number of winning pockets is the same.
A payout example in dollars
Suppose a player places $15 on the second column.
- If 20 lands, the bet wins because 20 belongs to the second column.
- The casino pays $30 profit and returns the original $15 stake.
- The total amount pushed back is $45.
- If 19, 21, 0, or 00 lands, the $15 bet loses.
“2 to 1” describes the profit, not the total returned. This is different from saying the player receives only twice the stake back.
Probability and house edge
Let:
- W = number of winning pockets, which is 12;
- T = total pockets on the wheel;
- b = amount wagered.
The probability of winning is:
P(\text{win})=\frac{W}{T}The expected value of one column wager is:
EV=b\left(2\frac{W}{T}-1\frac{T-W}{T}\right)The 2 represents the profit on a win. The 1 represents the full stake lost on any other pocket.
| Wheel | Winning probability | Losing pockets | Expected loss on $10 | House edge |
|---|---|---|---|---|
| Single-zero, 37 pockets | 12/37 = 32.43% | 25 | $0.27 | 2.70% |
| Double-zero, 38 pockets | 12/38 = 31.58% | 26 | $0.53 | 5.26% |
| Triple-zero, 39 pockets | 12/39 = 30.77% | 27 | $0.77 | 7.69% |
For a $10 double-zero column bet:
EV=$10\left(2\times\frac{12}{38}-\frac{26}{38}\right)=-$0.5263The result does not predict that every $10 spin loses 53 cents. It means the average loss approaches about 53 cents per $10 of column action over a very large number of independent spins.
The house edge rises when extra zero pockets are added because the payout remains 2 to 1 while the number of losing outcomes increases.
Betting two columns changes coverage, not the price
A player can place $10 on two different columns, creating $20 of total action and covering 24 of the 36 numbered pockets.
If either selected column wins, one $10 wager earns $20 profit while the other $10 wager loses. The net profit is therefore $10. If the unselected column or any zero lands, both wagers lose for a $20 loss.
On a single-zero wheel:
- win $10 on 24 of 37 outcomes;
- lose $20 on 13 of 37 outcomes.
EV=\frac{24}{37}($10)-\frac{13}{37}($20)=-$0.54That is still a 2.70% house edge on the $20 total wagered. Broader coverage produces more frequent small net wins and fewer larger losses, but it does not remove the casino margin.
The official rule is based on the layout
Massachusetts roulette rules define a column as a wager on one of 12 numbers in a single layout column and specify the 2-to-1 payout. The official roulette rules also show why zero is outside the three groups: the wager is tied to the 1–36 number grid.
This matters because players sometimes look at a run such as 3, 6, 9, 12 and assume the third column has become “hot.” The visible pattern was created after the outcomes occurred. Every valid spin begins with the same wheel pockets and the same posted payout; the felt does not steer the ball into one of its printed lanes.
Column, street, and dozen are easy to mix up
| Wager | Numbers covered | Typical payout | Placement |
|---|---|---|---|
| Column | 12 | 2 to 1 | Box below one vertical column |
| Dozen | 12 | 2 to 1 | 1st 12, 2nd 12, or 3rd 12 box |
| Street | 3 | 11 to 1 | Outer edge of one horizontal row |
| Six line | 6 | 5 to 1 | Junction between two horizontal rows |
The outside-bet guide explains the broader category, while straight-up bets sit at the opposite end of the coverage range.
What the dealer and player must both get right
A column wager is operationally simple, but disputes still happen when a chip is late, straddles two boxes, or is claimed after the result. The dealer identifies the winning number, clears losing outside bets, and pays the selected column at the posted odds. Procedures and hand movements vary by property, but the wager must be established before “no more bets.”
For the player, the useful checks are equally simple:
- Confirm whether the wheel has one, two, or three zero pockets.
- Place the chip fully inside the intended column box.
- Count the complete amount wagered if using two columns.
- Treat the bet as a priced 12-number group, not a forecast based on recent spins.
A column bet is easier to follow than a cluster of inside bets and wins more often than a single-number wager. It is not mathematically safer than other standard roulette bets carrying the same wheel-specific house edge. The number of covered pockets changes the rhythm of wins and losses; the zero pockets determine the long-run price.