What vigorish represents
If you convert every quoted price on a market into an implied probability and add them together, the sum exceeds 100 percent. The excess is the vigorish. On a two-way market with both sides priced at 1.91 decimal, the implied probabilities are 52.4 percent and 52.4 percent, summing to 104.8 percent. The 4.8 percent overshoot is the operator’s overround, or vig.
Vig is set by the trading desk and reflects competitive positioning, customer mix, and sport. Mainstream football and US team sports run tighter vigs than niche markets, because customer price sensitivity is higher and competitive pressure is stronger.
How vigorish is calculated
For any market with N outcomes priced at decimal odds d1, d2, dot dot dot dN, the overround is the sum of one divided by each price, minus one. A three-way football market priced at 2.10, 3.40, and 3.60 gives implied probabilities of 47.6 percent, 29.4 percent, and 27.8 percent, summing to 104.8 percent. The vig is 4.8 percent. The operator’s theoretical hold on balanced action across the market matches this number.
Realised hold is normally lower than theoretical because action does not balance perfectly across selections and sharp customers concentrate on the lower-vig side. Trading desks track theoretical and realised hold separately and explain the gap monthly.
Why vigorish matters in B2B
Vig is the primary lever on sportsbook gross margin. Setting it too high suppresses turnover and pushes customers to competitor books. Setting it too low erodes hold without proportionate volume gain. Trading-desk pricing strategy is built around target vig by sport, market, and customer cohort. For B2B vendors, the flexibility of the pricing engine to support per-market vig configuration is a procurement criterion. For operators, vig discipline across thousands of markets is a daily operational task, with deviations triggering trading-desk review.
Frequently asked questions about What Is Vigorish in Sports Betting?
Yes. Vigorish, vig, juice, overround, and margin are all terms for the same concept: the percentage by which the implied probabilities on a market sum to more than 100 percent. UK and European trading desks tend to say overround; US-influenced books say vig or juice.
Tier-one operators in mature European markets run match result vigs of around 4 to 6 percent. Niche markets and low-liquidity sports can run vigs above 10 percent. US team sports moneylines are typically priced at 4 to 5 percent vig in competitive markets.
Vig is the structural reason customer expected value is negative on a random bet. Sharp customers who consistently identify mispriced selections can overcome the vig; recreational customers cannot, which is why annualised sportsbook P&L is positive across the customer base.
No. Betting exchanges charge commission on net winnings instead of building margin into the price. That is why exchange prices on liquid markets run tighter than equivalent sportsbook prices.