What is a parlay bet?
A parlay bet (also called an accumulator or acca in the UK) combines multiple individual bets into a single wager where all selections must win for the bet to pay out. The odds of each selection multiply together, creating much higher potential returns than any single bet — but a single loss eliminates the entire parlay.
How parlay odds work
If you combine three bets at 2.0 odds each, the parlay pays at 2.0 × 2.0 × 2.0 = 8.0. A £10 parlay wins £80 (£70 profit) versus £10 profit on each individual leg bet separately. The potential return grows quickly with each added selection. The catch is that all selections must win — one loss and the entire stake is lost.
Parlay vs single bets
From an expected value standpoint, parlays are worse than placing the same bets separately because each leg carries the bookmaker’s margin and that margin compounds. But they offer leverage — small stakes can produce large payouts. Parlays are popular for sports betting but the format isn’t typically used in casino table games (where each hand or spin is already self-contained).