What is Odds bet?
The odds bet in craps is an additional wager placed behind a pass, don't pass, come or don't come bet after a point is set; it pays true odds and has no house edge.
Taking odds on a pass bet pays 2 to 1 on a point of 4 or 10, 3 to 2 on 5 or 9, and 6 to 5 on 6 or 8, exactly matching the probabilities. Laying odds on the don't side pays the reverse. Because the payout equals the true odds, the expected value of the odds bet alone is zero.
Casinos limit how much odds a player may take, commonly expressed as a multiple of the line bet, such as 3x, 4x and 5x. Higher allowed odds lower the combined house edge of the line bet plus odds.
The odds bet is the only common casino wager with no built-in edge, which is why it is often cited in explanations of casino maths.