Craps Buy Bet Vig: How Much Fee Is Actually Bleeding Your Bankroll?
The commission on a Buy bet is a straight 5% of your wager, rounded to the nearest dollar, and that single number decides whether the move is a sharp play or a slow execution. Most players never run the math. They hear "Buy the 4 and 10" and assume it beats Place betting. Sometimes it does. Sometimes the house is quietly taxing you into the dirt, and you do not notice until the session is over. 😤
The Raw Mechanics of the 5% Commission
Here is the cold reality. A $20 Buy bet on the 4 or 10 costs you $1 upfront. That $1 is the vig, and it is collected the moment the wager hits the felt. You are not paying it on a win. You are paying it on placement. That distinction matters more than any payout table you have ever memorized, because it changes the effective house edge on every single roll, not just the resolved ones.
Run the true odds. The 4 and 10 pay 2:1. A $20 Buy returns $40 in profit plus your $20 stake, minus the $1 you already handed over. Net win: $39 on a $20 risk. Compare that to a Place bet on the 4 or 10, which pays 9:5. A $20 Place returns $36. The Buy bet wins by $3 per hit. That is the entire case for buying, and it collapses the second the commission structure changes.
Where the Vig Kills the Edge
Buy bets on the 4 and 10 are the only ones where the standard 5% commission produces a house edge under 2%. On a $20 wager, the edge sits at roughly 1.67%. On a $25 Buy, the vig is $1.25, rounded to $1 or $2 depending on the house. If they round up, your edge balloons past 2.5% instantly. That is the trap. The Craps Buy Bet Vig is not a fixed cost. It is a variable tax that shifts with your bet size and the casino's rounding policy.
Buy the 5 and 9? The true odds pay 3:2. A $20 Buy returns $30 profit. A $20 Place on the 5 or 9 pays 7:5, returning $28. The Buy wins by $2. But now your $1 vig represents 5% of a $20 bet, and the house edge climbs to 2%. Buy the 6 and 8? The true odds pay 6:5. A $20 Buy returns $24. A $20 Place pays 7:6, returning $23.33. The Buy wins by 67 cents. You paid $1 for that. You are underwater before the dice leave your hand. 😵
Commission Timing: Upfront vs. On Win
Some houses only collect the vig when the bet wins. That single policy change flips the entire calculation. If you pay $1 only on a resolved win, the house edge on a $20 Buy 4 or 10 drops to roughly 0.83%. That is elite territory. That is better than most blackjack side bets and every prop bet on the layout. But do not assume every pit operates this way. Ask the dealer. Watch the drop. The timing of the commission on a Buy bet is the difference between a viable strategy and a donation.
Bet Sizing and the Rounding Scam
Here is where the math gets vicious. A $20 Buy on the 4 or 10 with a $1 vig is the sweet spot. A $25 Buy with a $1.25 vig rounded up to $2 pushes the house edge to 4%. A $50 Buy with a $2.50 vig rounded up to $3? You are better off placing the bet and eating the inferior payout. The rounding is not a rounding error. It is the house's edge, baked into the chip tray.
The only way to neutralize it is to size your Buy bets in multiples of $20. Every $20 increment generates exactly $1 in commission at the standard rate. $40 Buy, $2 vig. $60 Buy, $3 vig. Clean numbers, no rounding leakage. The moment you deviate from that ladder, the 5% commission starts eating your expected value alive. 🎯
The Only Buy Bets Worth Making
Buy the 4 and 10. That is it. The 5 and 9 are marginal at best, and only if the house collects on win. The 6 and 8 are a mathematical joke. You are paying a premium for a payout that barely beats the Place bet, and the vig devours the difference before the shooter even establishes a point. If a dealer pushes you toward buying the 6 and 8, they are either misinformed or hoping you are. Either way, the math does not lie.
Track every commission you pay across a session. A $20 Buy 4 hit three times costs you $3 in vig. That is 15% of your original stake gone to fees, regardless of whether those bets won or lost. Over a four-hour session with 60 resolved bets, the commission alone can exceed your average win rate. The dice do not care about your strategy. The vig does not care about your bankroll. It just collects.