Vigorish

Vigorish is a fee, commission, or pricing deduction attached to a wager. Casino players usually shorten it to vig. In craps, the term is most closely associated with buy bets and lay bets, where the underlying number can be paid at true odds but the casino charges a fee for offering that price.

The amount printed as “5% vig” is not enough to evaluate the bet. You also need to know what the percentage is applied to, when it is collected, and how it is rounded.

Vig is not a synonym for house edge

The two concepts are related but different.

• Vigorish is a fee or pricing method.
• House edge is the final expected casino advantage after probabilities, payouts, fees, pushes, and other rules are included.

A wager can have a house edge without a separately stated vig because the payoff is below fair odds. A wager can also be paid at true odds but become negative expectation because a commission is charged.

The glossary entry for vig explains the shortened table term. This page focuses on the mathematics and procedures behind it.

Four questions determine the actual cost

Before judging a commissioned wager, ask:

1. What is the fee rate? A casino may quote 5%, but another rate or minimum charge may apply.
2. What is the fee base? It may be calculated on the amount wagered, the amount won, or the amount the player is trying to win.
3. When is it collected? The fee may be taken when the bet is placed, only after a win, when the bet is removed, or under another posted method.
4. How is it rounded? Chip denominations and minimum fees can make a nominal 5% charge effectively higher on small bets.

This is why two tables that both advertise a 5% vig may not offer the same value.

Buy bets: a clear example

A buy bet in craps wagers that a selected number will appear before 7. The casino generally pays true odds and charges vigorish.

Consider a $20 buy bet on 4:

• 4 can be rolled in 3 combinations;
• 7 can be rolled in 6 combinations;
• ignoring other rolls that leave the wager unresolved, the probability that 4 wins the decision is 3/(3+6), or 1/3;
• the true-odds win is $40;
• assume a $1 vig.

If the $1 is collected only when the bet wins, the true-odds part of the wager has zero expectation and the expected fee per resolved decision is:

Expected fee = probability fee is charged × fee

Expected fee = 1/3 × $1 = $0.333

Relative to the $20 amount wagered:

$0.333 ÷ $20 = 1.667% expected cost per resolved decision

The player’s winning profit is $39 after the fee, but the cleanest way to understand the edge is that a fair underlying bet has acquired an average fee of one-third of a dollar.

If the same $1 is collected up front on every resolved bet, the expected fee is $1 rather than $0.333. The nominal rate has not changed, but the collection rule has tripled the expected charge in this example.

The calculation assumes the fee is exactly $1 with no refund or different house procedure. Always use the posted rule for the table being played.

Lay bets use a different-looking base

A lay bet wagers that 7 will appear before the selected number. Because the player is laying odds, the amount risked is usually larger than the amount won.

Suppose a player lays 4 for $40 to win $20. A quoted 5% commission might be calculated on the $20 potential win, producing a $1 fee. If someone instead assumes 5% of the $40 amount laid, they would expect $2. The percentage is identical; the base is not.

That is why a player should never infer the commission from the word “five percent” alone. The dealer or posted rules should make clear what the percentage applies to.

Rounding can dominate small wagers

Casino chips do not always allow exact percentage calculations. A property may use minimum commission units or require wager multiples that produce clean payouts.

If a theoretical fee is $0.50 but the table collects $1, the effective visible fee is not 5% of a $10 base; it is 10%. Larger properly structured wagers may receive closer-to-nominal pricing because the chip work rounds cleanly.

This does not mean a player should increase the wager merely to obtain a cleaner percentage. A lower percentage on a larger amount can still create a larger expected dollar loss.

For any fee:

Effective fee rate = fee charged ÷ fee base

The “fee base” must be defined first. Without it, the result is meaningless.

Commission is part of procedure as well as math

The dealer has to know:

• which wagers require commission;
• the approved fee base;
• whether the fee is collected on placement, on a win, or later;
• the wager multiples needed for correct payouts;
• how to handle presses, reductions, removals, and unresolved bets;
• how to display or record commission so another dealer can continue accurately.

The official Massachusetts craps rules, for example, allow approved buy and lay wagers with a commission capped at 5% and distinguish between methods that collect the fee when the bet is made and methods that collect it only when the wager wins. Rules and approved procedures differ by jurisdiction and property.

The casino should not improvise a fee after the outcome. The player should be able to determine the rule before wagering.

Vigorish outside craps

The word has broader uses.

Baccarat commission

Traditional Banker wagers commonly pay even money less a commission. The commission is often called vigorish, although baccarat has its own commission procedure and recordkeeping issues.

Sportsbook language

In sports betting, “the vig” often refers to the margin embedded in the prices offered on all sides of a market. It may not appear as a separate fee at the counter; it is built into the odds.

Informal casino usage

People sometimes use vigorish loosely for any house charge. That can obscure the actual mechanism. A reduced payoff, a fixed fee, a percentage commission, and a built-in overround do not behave identically.

True odds do not guarantee a fair bet

A common misunderstanding is: “The number pays true odds, so there is no house edge.”

True odds describe the gross payout before the fee. Once vigorish is attached, the complete wager is no longer fair. The correct comparison is not merely probability versus gross payout. It is probability versus net outcome after every mandatory charge.

The odds bet in craps is useful as a contrast. Properly structured free odds are normally paid at true odds without a separate house charge, although they must be attached to an underlying line wager that has its own edge. A buy bet may stand on its own but carries vig.

Comparing two vig rules

Suppose two casinos offer the same $20 buy bet on 4 with a $1 fee:

The first rule is mathematically better for the player, all else equal. Yet session results can still reverse the experience: a player who loses the first decision pays no win-only vig but loses the $20 wager; a player who wins pays the fee and still earns $39. Expected cost is an average, not the next outcome.

A practical way to read the table

Before placing a buy or lay bet:

• confirm the payout odds;
• ask whether vig is charged up front or only on a win;
• confirm whether the fee is based on the stake or potential win;
• ask about minimum commission and rounding;
• use a wager amount that the table can settle cleanly;
• compare the full expected cost with simpler alternatives.

The pages on buy bets, lay bets, and true odds versus casino payouts provide the game-specific context.

A small fee can look harmless because it is only one chip. Repetition is what gives it weight. Vigorish should be evaluated the same way as any casino price: define the wager, probability, net payout, fee base, fee timing, and total action before deciding what it really costs.