What Is the Vig? A Plain-English Guide to Sportsbook Vigorish (2026 Edition)
The "vig" (short for vigorish) is the built-in edge that sportsbooks add to betting odds, ensuring they profit regardless of the game's outcome. In 2026, understanding the vig is crucial for any bettor: it’s the hidden fee inside every line, and it directly impacts your potential returns.
What Is the Vig? (Direct Answer)
The vig, or vigorish, is the sportsbook’s margin: an extra percentage built into the betting odds that guarantees the bookmaker a profit over time. For example, standard −110/−110 lines on both sides of a game include about a 4.76% vig, meaning the sportsbook expects to keep $4.76 for every $100 wagered, no matter the result. Knowing how to spot and calculate the vig helps you compare odds and understand your real cost of betting.
Why Sportsbooks Charge a Vig
Sportsbooks are businesses, not charities. The vig is how they make money, covering operational costs and ensuring profitability. Instead of charging an explicit fee, they shade the odds so that—if bets are evenly matched on both sides—the book wins a small amount regardless of the outcome.
For example, if you bet on either side of an NFL spread at −110, you must risk $110 to win $100. The extra $10 is the vig baked into the odds. If equal money comes in on both sides, the book pays $100 to the winner and keeps $10 from the loser, netting a tidy profit.
How the Vig Works: A Concrete Example
Let’s break down a typical NFL spread market:
| Team | Odds (American) | Odds (Decimal) |
|---|---|---|
| Bears | −110 | 1.91 |
| Packers | −110 | 1.91 |
Suppose two bettors each wager $110—one on the Bears, one on the Packers. Regardless of the outcome:
- Winner receives $110 (stake) + $100 (profit) = $210
- Loser forfeits $110
- Book takes in $220, pays out $210
- Book profit: $10
This $10 is the vig, and it represents a 4.76% margin on the $210 returned to players ($10 / $210 ≈ 4.76%) or a 4.55% hold on total bets ($10 / $220 ≈ 4.55%).
Vig Formula (for Two Outcomes)
To see the vig in the odds, convert both prices to implied probabilities and add them together:
- Bears (−110): 110/(110+100) = 0.5238 (52.38%)
- Packers (−110): 110/(110+100) = 0.5238 (52.38%)
- Total implied probability: 52.38% + 52.38% = 104.76%
The extra 4.76% over 100% is the vig.
You can try this calculation for any odds using ArbMonster’s vig calculator or check measured live sportsbook vig across 20+ US books.
Impact of Vig on Payouts and Arbitrage
The vig reduces your expected return compared to the true probability of the event. If you consistently bet into high-vig markets, your break-even win rate must go up, or you’ll lose money over time.
For arbitrage seekers: Lower-vig books offer more and better opportunities. Since the vig is the primary "cost" on sportsbook bets (they don’t charge explicit fees), knowing the real margin is essential when comparing prices between sportsbooks and prediction markets like Kalshi or Polymarket. ArbMonster automates this comparison and shows every number net of all fees, including vig, at fillable size.
Vig on Different Bet Types and Sports
Not all markets are −110/−110. Vig varies by sport, bet type, and even by book. Here’s a table of typical overrounds (the sum of implied probabilities over 100%) on common US sportsbook lines in 2026:
| Bet Type | Typical Odds | Overround (%) | Hold (%) |
|---|---|---|---|
| Spread/Total | −110/−110 | 104.76 | 4.55 |
| Moneyline | +140/−160 | 104.76 | 4.55 |
| Three-way | +150/+200/+220 | 106–108 | 6–8 |
| Futures | Varies (high) | 120+ | 15–30 |
- Overround is the sum of the implied probabilities in the odds. Anything over 100% is the bookmaker’s edge.
- Hold is what the book expects to keep as a % of all bets if the market is balanced.
For more details, see ArbMonster's glossary: vig and hold.
Worked Example: Calculating Vig on a Three-Way Market
Suppose you see these odds on a soccer match:
| Outcome | American Odds | Decimal Odds |
|---|---|---|
| Home Win | +130 | 2.30 |
| Draw | +230 | 3.30 |
| Away Win | +200 | 3.00 |
First, convert to implied probabilities:
- Home Win: 100 / (130 + 100) = 0.4348 (43.48%)
- Draw: 100 / (230 + 100) = 0.3030 (30.30%)
- Away Win: 100 / (200 + 100) = 0.3333 (33.33%)
Sum: 43.48% + 30.30% + 33.33% = 107.11%
So, the vig here is 7.11%.
If you want to automate this calculation for any odds format, use the ArbMonster Vig Calculator.
How Prediction Market Fees Compare
Unlike sportsbooks, prediction markets like Kalshi and Polymarket charge explicit taker fees based on trade size and price. Their fees peak at the 50¢ price point, then drop toward zero near 1¢ or 99¢. For a detailed side-by-side, see ArbMonster: Kalshi vs Polymarket and venue fee schedules.
When comparing opportunities across venues, always consider both the sportsbook vig and the prediction market fee—both are real costs that reduce your potential edge.
Key Takeaways
- The vig (vigorish) is the hidden margin built into sportsbook odds and is typically around 4.5–5% for spread markets.
- Vig means you must win more than 50% of bets at −110 to break even.
- You can calculate the vig by adding implied probabilities and subtracting 100%.
- Vig varies by market, sport, and book—always check the real cost before betting.
- ArbMonster automates vig measurement and opportunity identification, net of all fees, for 20+ books and major prediction markets.
FAQ
Q: What does “vig” mean in sports betting?
Vig, short for vigorish, is the built-in margin or commission that sportsbooks include in their odds. It’s how they ensure a profit regardless of the outcome. The vig is not an explicit fee; it’s hidden in the odds you see.
Q: How can I calculate the vig for any set of odds?
To calculate vig, convert each outcome’s odds to an implied probability, sum them, and subtract 100%. For example, two sides at −110 each add to 104.76%, so the vig is 4.76%. Online tools like ArbMonster’s Vig Calculator automate this.
Q: Why does the vig matter to bettors?
The vig reduces your expected return and means you need to win at a higher rate to break even. If you ignore the vig, you may overestimate your potential profit or value compared to the real math.
Q: Is the vig the same as the “hold”?
They’re related but not the same. The vig (overround) is the total margin built into the odds, while the hold is the percentage of total bets the book expects to keep if action is balanced. For two-sided −110 lines, the vig is 4.76% and the hold is 4.55%.
ArbMonster is a data service. Nothing here is financial or betting advice; markets carry risk, venues have age and jurisdiction restrictions, and you are responsible for verifying everything before acting.