Parlay Betting Guide — How Parlays Work in South Dakota

What Is a Parlay?

A parlay is a single bet that links 2 or more individual bets ("legs"). Every leg must win for the parlay to pay out. If even one leg loses, the whole parlay is lost.

Example: Vikings -3 + Twins moneyline + Packers/Bears over 45.5 = a 3-leg parlay. All three must win.

Why Parlays Pay So Much

Parlay odds multiply together, not add. Each leg increases the total payout exponentially.

Example math (all -110 legs):

• 2-leg parlay → +260 (bet $100, win $260)
• 3-leg parlay → +595 (bet $100, win $595)
• 4-leg parlay → +1228 (bet $100, win $1,228)
• 5-leg parlay → +2435 (bet $100, win $2,435)

The House Edge

Parlays are the highest-margin product for sportsbooks because the compounded -110 juice on each leg adds up fast. A 4-leg parlay's true odds would pay closer to +1500 if priced fairly — the +1228 listed represents the book's ~5% margin per leg, compounded.

Over thousands of parlay bets, the average bettor loses roughly 25-35% of their wagered amount on a 4-leg parlay strategy. That's much worse than the ~5% expected loss on straight bets.

Same-Game Parlay (SGP)

BetMGM's SGP product lets you combine multiple bets from the same game (e.g., Vikings -3 + Justin Jefferson over 90 receiving yards + game total over 47.5). Because the legs are correlated, BetMGM uses adjusted pricing — usually worse value than regular parlays, but a popular product for single-game viewing parties.

ISI and IGT books in Deadwood have limited or no SGP product. If SGPs are your thing, stick to Tin Lizzie or Cadillac Jack's.

When Parlays Make Sense

Parlays make sense for entertainment, social viewing, and longshot lottery-ticket fun. They do not make sense as a profitable strategy. If your goal is to actually beat the books, stick to straight bets or low-leg (2-3 leg) parlays where the math is less brutal.