The free odds bet, the only fair bet in the casino

Let's start with the basics: what is the free odds bet?

The free odds bet, often just called "taking odds" or "laying odds," is an extra wager you can add once a Pass Line, Don't Pass, Come or Don't Come bet has a point established. It isn't offered on the come-out roll, and it isn't available on its own, it only exists as a top-up behind a bet you've already made. What makes it unusual is the payout: every other bet on a craps table pays a round number that's been nudged in the casino's favour (Place 6 pays 7:6 instead of the true 6:5, for instance), but the odds bet pays the exact true probability of the point repeating before a 7. That's the whole story behind why it's the one bet in the building with genuinely no built-in house edge.

The odds tables, worked out properly

The numbers below come from working through every dice combination directly, the same approach used across every calculator on this site, rather than being copied from a chart. Combined edge is the effective house edge across your whole wager, flat bet plus odds, at each multiple.

Notice the edge keeps shrinking as the multiple climbs but never quite hits zero, and it never will. The flat Pass Line or Don't Pass bet still carries its own fixed edge, the odds bet is just spreading that same fixed pound-and-pence loss across a bigger total stake. Bet enough in odds relative to your flat bet, and the blended percentage gets vanishingly small, which is exactly why serious low-edge players max out their odds rather than raising their flat bet.

Why the odds bet itself carries no house edge

You might be right to wonder how a casino can offer any bet with genuinely nothing built in for itself, and the honest answer is that it doesn't mind, because the odds bet only ever gets made behind a bet that already has an edge. Take a point of 6: there are 5 ways to roll it and 6 ways to roll a 7, so a 6 is made before a 7 exactly 5 times out of every 11 decisions. A fair, zero-edge payout on that would be 6:5, and that is precisely what the odds bet pays on 6 or 8. The same logic holds at every point, 2:1 on 4 or 10 (3 ways vs 6), and 3:2 on 5 or 9 (4 ways vs 6). The casino makes its money entirely from the flat bet sitting in front of the odds, and is happy to offer a genuinely fair side bet as an incentive to get more action on the table.

Table maximums and the "3-4-5x" rule explained

Odds limits are usually written on the table felt as "3-4-5x Odds" rather than a single flat number, and that specific combination isn't arbitrary. A point of 4 or 10 is the hardest to make, so the casino allows a smaller multiple, 3x, a point of 6 or 8 is the easiest, so it allows more, 5x, with 5 or 9 sitting in between at 4x. Structured this way, the most you can ever have riding on odds is capped at roughly the same total regardless of which point gets set, which is tidier for both the pit and the player than a single number that would either be too generous on the easy points or too stingy on the hard ones. The combined 0.374% Pass Line edge under 3-4-5x sits neatly between the flat 3x and flat 5x rows in the table above, exactly where you'd expect it to land.

Once you've got the odds bet down, the honest maths behind whether AI or "dice control" can do anything to shift these numbers is covered on the Craps AI hub page, short answer: no, these figures are fixed by the dice, nothing changes them. For the underlying probability of any given roll, including why 6 and 8 come up more often than 4 and 10, the dice probability calculator breaks down all 36 combinations one number at a time.