A parlay (also "accumulator", "multibet", "combinada", "combinata") is a single bet that combines multiple selections, all of which must win for the bet to pay out, at multiplied odds.
Parlay / Multibet
TL;DR: A parlay (also "accumulator", "multibet", "combinada", "combinata") is a single bet that combines multiple selections, all of which must win for the bet to pay out, at multiplied odds.
What it means
A 4-leg parlay with each leg priced at 1.91 returns 13.31× the stake if all four hit. Players love parlays because the upside dwarfs the stake; sportsbooks love them because the compounded margin makes parlays massively profitable. A 4-leg parlay with 4.5% vig per leg compounds to about 17% theoretical margin — three to four times the margin of a single straight bet.
In the US, "parlay" is the term; in the UK and AU, "accumulator" or "multi"; LATAM Spanish uses "combinada" or "parlay"; Italian "schedina". Same product, same economics.
Formula / How it's measured
Parlay odds = product of leg decimal odds. Parlay margin = 1 − (1 / Π(legᵢ decimal odds × leg-iᵢ true prob)).
Example: 4 legs, each at 1.91 decimal (fair=2.0, 4.5% vig per leg). Parlay odds = 1.91⁴ ≈ 13.31. True parlay probability = 0.5⁴ = 0.0625 → fair odds 16.0. Book margin on parlay ≈ (16.0 − 13.31)/16.0 = 16.8%.
Why it matters for operators
Parlays drive both top-line GGR and recreational engagement. Hold percentage on parlays is typically 2–4× higher than on single bets. They're also the format most affected by sharps using correlated parlays and same-game-multi exploits — risk teams pay close attention.
Common benchmarks (2026)
- Parlay share of US sportsbook handle: 25%–45%
- Parlay share of NGR: 50%–75% (much higher than handle share)
- Average legs per parlay: 3.5–4.8
- Parlay hold percentage: 15%–30%
- Same-game parlay (SGP) share of total parlay handle: 35%–55%
Common mistakes
- Allowing correlated legs without correlation pricing — sharps exploit
- Letting recreational players cash-out parlays too cheaply
- Parlay-only bonuses encouraging long-shot accumulators with poor brand consequences when they lose
See also