Parlay Betting Explained: How Parlays Work and When They Make Sense
Parlays are the most popular bet type in US sports betting. Combine several picks into one ticket and a small stake can return a big payout. But that bigger payout comes with a much bigger risk, and a bigger edge for the sportsbook. Here is how parlays work and how to use them sensibly.
What is a parlay?
A parlay (also called an accumulator) combines two or more bets, called legs, into one wager. Every leg must win for the parlay to pay out. If one leg loses, the whole ticket loses. If a leg is cancelled or pushes, it is usually removed and the payout recalculated.
How parlay odds are calculated
Convert each leg to decimal odds and multiply them together.
- Leg 1: -110 → 1.91
- Leg 2: -110 → 1.91
- Leg 3: +150 → 2.50
Parlay odds: 1.91 × 1.91 × 2.50 = 9.12. A $10 bet returns $91.20 in total, or $81.20 profit.
Why parlays favour the sportsbook
Every bet you place includes the sportsbook's margin. In a parlay, those margins multiply. A standard -110 line has a margin of about 4.5%. Over a three-leg parlay of -110 bets, the house edge grows to roughly 12–13%, and it keeps rising with every leg you add. That is why sportsbooks promote parlays so heavily.
Two -110 legs each have about a 50% chance of winning (ignoring the margin), so the parlay has about a 25% chance. Three legs fall to 12.5%, four to about 6%.
Same-game parlays
Same-game parlays combine bets from one event, such as a team to win, a quarterback over on passing yards and the game total over. Because these outcomes are related, sportsbooks adjust the price, and they usually build in an even bigger margin than standard parlays. They are fun, but rarely good value.
Round robins
A round robin splits your picks into several smaller parlays. With four picks, a round robin by twos creates six two-leg parlays, so you can still get a return if one pick loses. It reduces variance compared with one big parlay, but it costs more because you are placing several bets.
When parlays make sense
- Small stakes for entertainment, when you accept that most tickets will lose.
- Parlay boosts and insurance, which can offset part of the built-in margin.
- Genuinely correlated picks that the sportsbook hasn't priced in. These are rare and quickly corrected.
- When you find value on every leg. If each leg is a good bet on its own, combining them multiplies that edge, along with the variance.
How the odds stack up: probability by number of legs
Assuming each leg is a coin-flip at -110 odds:
| Legs | Chance all win | Approx. payout on $10 |
|---|---|---|
| 2 | 25% | $36 |
| 3 | 12.5% | $70 |
| 4 | 6.3% | $133 |
| 5 | 3.1% | $254 |
| 6 | 1.6% | $484 |
The payouts grow quickly, but the chance of hitting falls even faster, which is why big parlays rarely land.
Teasers: a parlay variation
Teasers let you move the point spread or total in your favour on each leg, for example by six points in the NFL, in exchange for a lower payout. They work best when the adjusted lines cross key numbers like 3 and 7 in football. Outside those situations, teasers usually carry a high margin.
Parlays and bankroll management
Because parlays lose most of the time, stake them smaller than your single bets. A common approach is to keep parlays to a small fixed share of your betting budget, such as 5–10%, and never to increase stakes after a losing run.
Tips
- Keep parlays short. Two or three legs keep the house edge manageable.
- Shop for the best price on each leg before combining.
- Don't use parlays to "chase" losses; the low hit rate makes that a fast way to drain a bankroll.
- Check how the sportsbook handles pushes and void legs.
The bottom line
Parlays turn small stakes into big potential returns, but they lose far more often than they win and give the sportsbook a bigger edge. Use them sparingly, keep them short and treat them as entertainment. Find sportsbooks with parlay promotions on our sportsbooks page.
Frequently asked questions
What happens if one leg of my parlay pushes?
Usually the leg is removed and the parlay pays at the odds of the remaining legs. Rules vary by sportsbook, so check before betting.
Are same-game parlays good value?
Generally not. Sportsbooks price related outcomes carefully and usually add a bigger margin than standard parlays.
What is a round robin?
A round robin splits your picks into several smaller parlays, so you can still get a return if one pick loses. It costs more because you place multiple bets.
How many legs should a parlay have?
Two or three legs keep the house edge and variance manageable. Every extra leg multiplies the sportsbook's margin.