What is Dozen bet?
A dozen bet in roulette is a wager on one of three groups of twelve numbers, 1 to 12, 13 to 24 or 25 to 36, paying 2 to 1.
The chance of winning on a European wheel is 12 in 37. Zero is not part of any dozen, so it causes the bet to lose. The house edge is about 2.70% on single-zero wheels.
Dozen bets are outside bets placed in the boxes alongside the main number grid. Some players cover two dozens at once, which wins more often but returns only half the combined stake in profit.
The column bet is a similar 2 to 1 wager on twelve numbers arranged vertically on the layout. A dozen bet wins on average about once every three spins, ignoring zero. Because the payout is lower than for inside bets, losing streaks tend to be shorter, but over time the cost is identical. Betting systems that spread chips across two dozens or increase stakes after losses do not change the underlying edge, which remains about 2.70% per pound wagered on a European wheel.
