Parlay

A parlay is a single bet that links two or more selections together, where every selection must win for the bet to pay anything.

Definition

A parlay (the standard US term) combines multiple selections, or "legs," into one wager whose decimal odds are the product of the individual legs' odds, producing a much larger potential payout from a small stake. The trade-off is that all legs must win: a single losing leg voids the entire bet, so the probability of a payout falls sharply as legs are added. Because each leg carries the bookmaker's built-in margin, that margin compounds across the legs, making a parlay's expected value typically worse than betting each selection separately. When a leg ties or is voided (a "push"), operators usually recalculate the parlay on the remaining legs rather than treating it as a loss, though this handling varies.

Worked example

A bettor combines three selections into a parlay at decimal odds of 1.91, 2.00, and 1.50. The combined odds are 1.91 × 2.00 × 1.50 = 5.73, so a 20-unit stake returns 114.60 (a profit of 94.60) if all three legs win. The parlay's implied probability is about 17.5% (1 ÷ 5.73), far lower than any single leg's chance — and if even one selection loses, the whole ticket returns nothing.

Why it matters

Parlays are one of the most heavily promoted sportsbook products because they turn a small stake into a large advertised payout, which makes it important to understand what that payout costs. For a learner, the parlay is the clearest illustration of how multiplying odds also multiplies the operator's margin, so the long-run value is structurally worse than single bets even though the headline price looks attractive. For a professional, parlay hold is a major revenue driver and a responsible-messaging risk area: the large-payout framing can obscure a low win probability, so parlays must be presented as entertainment with a built-in cost, never as a route to income.

Related

Note: The concept is stable, but terminology is regional: "parlay" is US usage, while the UK and Europe say "accumulator" (or "acca") and Australia says "multi." Odds are shown as decimal, fractional, or American depending on the market. Operator- and jurisdiction-specific rules govern how pushed or voided legs are treated, whether correlated selections are allowed, and how same-game parlays are priced — verify against the specific book's rules.