Key Points
- A parlay links 2+ bets into one. All must win for the parlay to pay.
- Payouts grow exponentially with each leg added.
- The house edge compounds with every additional leg.
- Same-game parlays (SGPs) are the most popular format today.
- Use a parlay calculator to verify payouts before betting.
What is a Parlay?
A parlay is a single sports bet that combines two or more individual wagers (called "legs") into one bet. To win, every single leg must be correct. If even one leg loses, the entire parlay loses.
The appeal is straightforward: link together multiple bets you feel confident about, and turn modest individual payouts into a single, much larger payout.
How Parlay Payouts Work
Each leg's odds multiply together to produce the combined parlay odds. Let's say you parlay two teams, each -110:
- Convert -110 to decimal: 100/110 + 1 = 1.909
- Multiply both legs: 1.909 × 1.909 = 3.644
- Parlay decimal odds: 3.644
- On a $100 bet: $364.40 payout, $264.40 profit
Compare that with splitting the same $100 into two $50 straight bets at -110: winning both returns about $91 in profit. The parlay pays almost three times as much, but needs both to win.
The Math Behind Parlays
Parlays carry a higher house edge than individual bets. Each leg compounds the vig (sportsbook's commission), which means the more legs you add, the worse the math gets.
Two coin-flip legs would pay +300 if there were no vig. At -110 each, they pay about +264, and the difference is the book's edge.
Four coin-flip legs would pay +1500 at fair odds. At -110 each, they pay about +1228.
Types of Parlays
Standard parlays: the classic format. Each leg is from a different game.
Same-Game Parlays (SGPs): all legs from a single game. Hugely popular for major NFL and NBA games. Sportsbooks price these carefully because of correlation risk.
Round robins: a set of parlays covering every combination of your picks. A 3-team round robin creates three 2-team parlays.
When Do Parlays Make Sense?
From a pure expected value standpoint, parlays are almost never the mathematically optimal bet. However, there are a few situations where they make sense:
- Entertainment: For recreational bettors, a $20 parlay with a potential $200 payout is fun. Treat it like entertainment, not investment.
- Correlated parlays: If two outcomes are positively correlated (both benefit from the same underlying factor), a parlay may carry less risk than the book's pricing suggests.
- Teaser parlays: Specifically designed to cross key numbers, these can be mathematically defensible.
How to Calculate a Parlay
Use our Parlay Calculator to instantly calculate the combined odds, total payout, and implied win probability for any combination of legs and odds.
Common Parlay Mistakes
Adding legs for the sake of it: Every leg you add reduces your win probability. The dopamine of a bigger potential payout isn't worth the mathematical cost.
Parlaying correlated outcomes in different games: These don't offset each other.
Treating parlays as a strategy: Long-term parlay bettors lose more, on average, than single-game bettors.
The Bottom Line
Parlays are the most fun bet on the board, and one of the most profitable for sportsbooks. If you enjoy them, play them responsibly with a small portion of your bankroll. If you're trying to build a long-term winning strategy, single-game betting with proper bankroll management is the smarter path.