Why Parlays Have More Vig

Every leg of a parlay carries the sportsbook's margin. Because parlay payouts multiply, the margins multiply too — so the total margin on a parlay is far larger than on any single bet.

The short answer

One -110 leg carries about 4.8% implied margin. Two legs compound to roughly 9.2%. Three legs reach about 14.1%. By six legs, the estimated sportsbook margin approaches 27%. The ticket looks like a big payout, but a meaningful slice of it is compounded vig.

A worked example

ExampleThree -110 legs, each with an estimated fair probability of 50%. The parlay's fair chance is 0.5 × 0.5 × 0.5 = 12.5%, so fair odds are +700. A book paying +596 keeps the difference — an estimated margin of about 14% of the fair payout. The more legs you add, the wider that gap grows.

What this means in practice

Parlays are expensive entertainment. That does not make every parlay a bad bet, but it means the burden of proof is higher: the prices on your legs have to be good enough to overcome a compounded margin. This is exactly what an EVScout evaluation measures, leg by leg.

Try the math yourself

Vig Calculator

Related guides

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