Why Do My Parlays Always Lose?
The compounding math that makes parlays a sportsbook's best friend
7 min read
The Hard Truth About Parlays
If you've wondered "why do my parlays always lose?"—you're not alone, and you're not unlucky. Parlays are mathematically designed to lose more often than straight bets. The same mechanism that creates those exciting potential payouts is what makes them the sportsbook's most profitable product.
This isn't a conspiracy theory. It's compounding math. Let's break down exactly why your parlays keep busting—and what you can do about it.
The Vig Multiplies With Every Leg
On a straight bet at -110 odds, the vig (juice) costs you about 4.5%. You need to win 52.4% of bets just to break even. That's manageable.
But here's what happens with parlays: that edge doesn't just add—it multiplies.
The Math: 3-Leg Parlay Example
Fair odds (no vig): 50% × 50% × 50% = 12.5% win rate
Fair payout at 12.5%: +700 (7-to-1)
Actual sportsbook payout: +600 (6-to-1)
House edge: ~12.5% (vs 4.5% on straight bets)
The house edge nearly triples from a straight bet to a 3-leg parlay.
Straight Bet
- ~4.5% house edge
- Need 52.4% to break even
- Single point of failure
4-Leg Parlay
- ~20%+ house edge
- Need to win ALL legs
- Four points of failure
Why Sportsbooks Aggressively Promote Parlays
Ever notice how every sportsbook app pushes parlays? Same-game parlays on the homepage, parlay insurance promos, "easy parlay" builders. There's a reason for this: parlays are their highest-margin product.
The Business Reality
DraftKings and FanDuel don't promote parlays because they're good for you. State gaming reports consistently show that parlay bets generate 2-3x the profit margin of straight bets. When a sportsbook offers "parlay insurance" or "odds boosts," they've already calculated that they'll still come out ahead.
Realistic Parlay Win Rates
Let's assume you're a solid handicapper hitting 53% on straight bets (better than most). Here's what happens to your win rate as you add parlay legs:
53%
Straight Bet
28%
2-Leg Parlay
15%
3-Leg Parlay
8%
4-Leg Parlay
Even a winning bettor loses 85%+ of their 3-leg parlays
When Parlays Actually Make Sense
Parlays aren't always -EV. There are specific situations where they can be mathematically justified:
1. Combining +EV Bets
If each leg of your parlay is independently +EV, the parlay itself is +EV. Finding three +3% EV bets and combining them can be profitable—though you're increasing variance significantly.
2. Correlated Parlays
When outcomes are correlated (team wins AND covers), the true probability is higher than the book's math assumes. Some SGP combinations exploit this—but books are getting smarter.
3. Legitimate Odds Boosts
Sometimes promos offer genuine value. A boosted parlay paying +500 when fair odds are +400 is +EV. Use our EV calculator to verify.
What To Do Instead
If your goal is profitability (not just entertainment), here's the shift to make:
- Focus on straight bets with positive expected value
Lower house edge means your skill translates to profit more efficiently
- Use parlays strategically, not recreationally
Only parlay bets that are already +EV individually
- Evaluate odds boosts mathematically
Don't assume a 'boost' is actually good value—calculate it
- Track your parlay results separately
You'll likely find they underperform your straight bets significantly
Find +EV Bets Instead of Gambling on Parlays
We scan thousands of odds daily to find mathematically profitable straight bets. Skip the parlay gamble—bet with an actual edge.
The Bottom Line
Your parlays aren't losing because of bad luck or bad picks. They're losing because the math is stacked against you more heavily than with straight bets. The compounding vig turns a 4.5% house edge into 20%+.
If you enjoy parlays for entertainment with money you can afford to lose, that's fine. But if you're trying to be profitable, straight bets on +EV opportunities will outperform parlays every time over a meaningful sample size.
Frequently Asked Questions
Why do my parlays always lose?
Parlays lose frequently because each leg multiplies the house edge. A 3-leg parlay at -110 odds has roughly a 12.5% implied win probability, but sportsbooks pay as if it's around 10%. This compounding vig makes parlays mathematically unfavorable compared to straight bets.
Are parlays ever a good bet?
Parlays can be +EV in specific situations: when you find correlated outcomes the book doesn't properly adjust for, when combining multiple +EV straight bets, or when odds boosts offer genuine value. But recreational parlays picking random favorites are almost always -EV.
What percentage of parlays actually win?
The win rate depends on the number of legs. A 2-leg parlay wins about 25% of the time (assuming 50/50 bets), 3-leg about 12.5%, 4-leg about 6.25%, and so on. Each additional leg cuts your win probability roughly in half.
Why do sportsbooks promote parlays so heavily?
Because parlays are their most profitable product. The compounding vig means higher margins for the book. A bettor making straight bets at -110 faces ~4.5% house edge, while a 4-leg parlay can have 20%+ effective house edge. It's not close.
Should I stop betting parlays completely?
Not necessarily. If you enjoy the entertainment value and bet responsibly, small parlay wagers are fine. But if your goal is profitability, straight bets on +EV opportunities will mathematically outperform parlays over time.