The vig is the commission built into every set of odds a sportsbook posts. It doesn’t show up as a separate fee. It’s folded directly into the prices, which makes it easy to miss. This guide explains how to calculate it from any posted price, what winning rate you need just to break even, and how it varies across different market types and Canadian operators. By the end, you’ll have what you need to compare books more accurately and factor the margin into your betting decisions.
The Built-In Commission Behind Every Posted Price
Every price a sportsbook posts contains a built-in commission that funds the operator’s business. It’s not shown as a separate line item, a fee, or a percentage. It’s folded directly into the odds. Most bettors have been paying it on every wager they’ve ever placed without ever seeing it spelled out.
The sports betting industry uses several terms to describe the same thing: the commission built into posted odds. Whether you see “vig,” “juice,” “overround,” or “margin,” they all refer to the same mechanic. The sportsbook adjusts the price on both sides of a market so the implied probabilities add up to more than 100%, guaranteeing the operator collects more than the outcomes actually represent.
- Vigorish (vig): the original term for the commission embedded in a sportsbook’s posted prices
- Juice: North American slang for the same embedded commission, used widely in sports media
- Margin: the operator’s percentage advantage built into the odds on a given market
- Overround: the amount by which the sum of implied probabilities across all outcomes in a market exceeds 100%
- The cut / the take: informal terms for the share of every wagered dollar the sportsbook keeps through its pricing
- House edge: the structural advantage the operator holds over the bettor, expressed as a percentage of each wager
Unlike a brokerage fee or a service charge, the sportsbook’s commission is never itemised. It’s absorbed into the prices posted on both sides of a market, so it’s invisible to anyone reading the odds at face value. A bettor can place wagers for years, watch prices change, and assume those changes reflect shifts in probability, without ever noticing that the operator’s margin was in the original price and is still in the revised one. If you don’t decode the odds, you’ll consistently underestimate the true cost of every bet, because the stated price and the fair price are never the same number.
Calculating the Vig From Implied Probability
You can extract the vig from any posted price by converting each side’s odds into an implied probability and adding the results together. Because a sportsbook prices both outcomes, you need two conversions before you can apply the margin equation. The sections below give you the conversion formulas for American odds and then the equation that turns the summed probabilities into a vig percentage.
You need to convert American odds into implied probability figures before you can calculate any margin. Canadian sportsbooks default to decimal odds, but American odds appear regularly in cross-border content and are the standard format used to teach this math. The conversion formula changes depending on whether the line is negative or positive.
- Negative American odds: implied probability = |odds| ÷ (|odds| + 100)
- Positive American odds: implied probability = 100 ÷ (odds + 100)
Once you’ve converted both sides of a market into implied probabilities, the vig calculation is straightforward: Vig % = (sum of implied probabilities across both outcomes) minus 100%.
Here’s the logic: the true probabilities of two mutually exclusive outcomes must add up to exactly 100%. When a sportsbook prices a market, it inflates each side’s implied probability above its true level, so the two figures sum to more than 100%. That excess is the margin the sportsbook has built into the prices. The formula isolates that excess directly, without requiring any knowledge of what the sportsbook thinks the true probability actually is.
The -110/-110 Spread Worked Example
The standard example for illustrating the vig uses a point spread priced at -110 on both sides, which is the convention applied to NFL spreads and NHL puck lines across the industry. Because both sides carry identical odds, the math is clean and requires no asymmetric adjustments. This example is the reference point for most margin discussions.
At -110, a bettor risks CAD $110 to win CAD $100. To extract the vig, convert each side’s odds into an implied probability using the negative American odds formula: the absolute value of the odds divided by the absolute value of the odds plus 100. Both sides produce the same figure. Add those two figures together, and anything above 100% is the sportsbook’s embedded margin.
- Implied probability for Side A at -110: 110 ÷ (110 + 100) = 52.38%
- Implied probability for Side B at -110: 110 ÷ (110 + 100) = 52.38%
- Sum of both implied probabilities: 52.38% + 52.38% = 104.76%
- Vig: 104.76% − 100% = 4.76%
Because the -110 price requires risking $110 to return $100 in profit, you need to win 52.38% of your bets just to break even. That’s the floor before any profit is possible.
A 51% win rate sounds like a positive result, but at standard -110 pricing, it’s actually a losing record. The vig consumes the margin that a 51% win rate would otherwise generate, leaving you with a net deficit across a full season of wagers.
How the Vig Varies Across Bet Types
The standard point spread priced at -110 on both sides sits toward the lower end of the margin range a sportsbook applies across its full menu. Other market categories carry significantly higher embedded commissions, and the gap between the tightest and widest categories is not small. If you treat every market as carrying the same cost, you’ll consistently underestimate what you’re paying on props, futures, and parlays compared to a standard spread.
The table below shows the typical vig range across the main market categories available on Canadian sportsbooks. Margins widen as market structure moves away from the simple two-outcome format that allows the tightest pricing.
| Market Category | Typical Vig Range | Example Market Type |
|---|---|---|
| Two-way markets | 3.5%–5.5% | NHL puck line, NFL spread |
| Three-way markets | 5.0%–7.5% | Soccer 1X2 |
| Player props | 6.0%–10.0% | Individual player performance lines |
| Futures / outrights | 15%–30% | Season-winner markets |
| Three-leg parlays (effective) | 14%–17% | Compounded from individual leg margins |
Niche markets, such as lower-division European soccer or minor-league hockey, typically carry margins in the 8%–12% range. Sportsbooks have less pricing data on these events and face a higher risk that a bettor knows more about the outcome than they do. The wider margin acts as a buffer against that information gap. As a rule, the more obscure the market, the wider the margin, because pricing competition among operators is strongest in major-league markets.
When you combine multiple legs into a parlay, the margin from each leg doesn’t simply add together. It compounds multiplicatively. A three-leg parlay built from legs that each sit within a normal two-way range produces an effective margin of 14%–17% on the combined wager. The posted parlay price doesn’t show this compounding separately. The odds appear as a single number, and the accumulated margin is folded invisibly into that figure. The result is that a parlay costs more than placing each leg as a standalone bet at the same individual prices.
Vig Across the Canadian Sportsbook Market
Different Canadian sportsbooks price the same events at meaningfully different margins, and no regulation sets a ceiling on those differences. The launch of Ontario’s regulated iGaming market in April 2022 increased competitive pressure among domestic operators, which pushed average margins tighter than they were before regulation. The sections below show how margins vary across operators and sports, explain the regulatory framework behind it, separate vig from a related but distinct term, and show what margin differences cost across a full season.
The table below shows typical average margins for four Canadian sportsbooks across the three most-wagered sports domestically. The operators are listed in ascending order of their NHL margin, covering NHL, NFL, and soccer markets to show how margin behaviour changes across different market structures.
| Sportsbook | NHL Margin | NFL Margin | Soccer Margin |
|---|---|---|---|
| Bet365 Canada | 4.2% | 4.5% | 5.1% |
| DraftKings Canada | 4.8% | 4.6% | 5.4% |
| BetMGM Canada | 5.1% | 5.0% | 5.7% |
| Sports Interaction | 5.3% | 5.2% | 5.9% |
Ontario’s regulated iGaming market launched on April 4, 2022, under iGaming Ontario (iGO), which was established on July 6, 2021. Bringing multiple licensed operators into a single competitive provincial market increased pricing pressure, and average margins across domestic sportsbooks are tighter than they were before regulation. No federal or provincial regulator in Canada sets a maximum margin sportsbooks may charge. iGaming Ontario’s mandate covers operator licensing and responsible gambling standards, not odds pricing or margin caps. Posted prices are not policed for fairness.
The gap between a 3.5% margin operator and a 10% margin operator on the same annual bet volume works out to roughly $1,625 CAD across a single season. That reframes what looks like a small percentage difference per bet. A spread of a few margin points, applied repeatedly across a season’s worth of wagers, adds up to a real dollar difference. The more you bet, the more that gap costs you.
Line Shopping as the Practical Response to Margin
Because Canadian sportsbooks embed different margins into the same event, the posted price for an identical wager varies across operators. Comparing those prices, a practice known as line shopping, is how you see margin differences directly rather than inferring them from formulas. The variation isn’t random. It reflects the fact that operators set their own margins independently and no regulator in Canada caps what those margins can be. Checking prices across multiple platforms is, in effect, reading the competitive market itself.
When the same market, say an NHL moneyline, is displayed across multiple Canadian sportsbooks at the same time, the differences in posted odds are a direct expression of the differences in embedded margin. A price that converts to a 52.5% implied probability on one platform and a 53.5% implied probability on another isn’t a rounding coincidence. It’s a measurable difference in the margin each operator has built into that side of the market.
Ontario’s regulated iGaming market, which launched on April 4, 2022, brought more competing licensed operators into the Canadian market, making margin variation across platforms more visible than it was before regulation. Comparing prices across those operators makes it easier to read posted odds as outputs of a competitive pricing process rather than as fixed or authoritative values. The same decimal figure that looks neutral on a single platform becomes legible as a margin decision the moment you place it beside a competing price for the same outcome.
Reading Odds With the Cost Made Visible
Once you understand the vig, a posted price stops being just a number and becomes a pricing decision you can read. A bettor who can extract the margin from any odds screen isn’t reading a number at face value anymore. They’re reading the competitive and structural conditions under which that number was set, across market types and operators alike.
