Jimmy Boyd in 
Ever find yourself lured by the huge payout on a longshot bet? You’re not alone.
Many recreational bettors can’t resist the “big score” potential of a heavy underdog. Throw a few bucks on a 50-to-1 outsider and imagine the payday – it’s a thrilling dream.
But here’s the kicker: sportsbooks love when we chase those long shots. There’s a well-known quirk in betting markets called the favorite–longshot bias, and if you’re not aware of it, it could be quietly draining your bankroll.
In plain English, this bias means bettors tend to overvalue longshots and undervalue favorites. Let’s see how understanding this concept can make you a smarter bettor.
What Is the Favorite-Longshot Bias?
The favorite-longshot bias is a fancy term for a simple idea: underdogs (longshots) are given too much credit, while favorites don’t get enough love from bettors and oddsmakers. In other words, people overestimate the chances of a longshot winning and underestimate how often the favorite wins.
This bias has been observed across many sports and betting markets for decades. It was first noticed in horse racing, but it shows up in everything from soccer to basketball to tennis.
To illustrate, imagine a two-horse race. One horse is a strong favorite at 3-to-1 odds, meaning a $1 bet wins $3. The other is a massive underdog at 100-to-1 (a $1 bet would win $100).
If bettors were perfectly rational and odds were perfectly accurate, a 100-to-1 horse should seldom win. But due to the favorite-longshot bias, the true odds might be more like 300-to-1 for that longshot.
In reality, the longshot is even less likely to win than people think. Betting on that 100-to-1 underdog is a much worse deal than it appears while betting on the 3-to-1 favorite is relatively better.
Studies have found that over the long run, you might lose around 5% of your money betting on favorites, but you could lose 40% betting on extreme longshots.
Yikes! That means for every $100 wagered, favorites might cost you $5 on average, whereas longshots could cost you $40.
No wonder the house doesn’t mind when you take a flier on a Cinderella story.
So, the favorite-longshot bias is telling us: “Big underdogs are overpriced (bad value), and big favorites are underpriced (good value) relative to their true chances.” It’s a counter-intuitive truth that many bettors overlook.
We get it – backing the longshot is exciting and backing the favorite feels boring. But this bias shows that what’s exciting isn’t always profitable.
Why Do Bettors Fall for Longshots? (The Psychology Behind It)
If betting on longshots is often a losing proposition, why do so many of us do it? Several human quirks and behaviors explain this favorite-longshot bias:
- We Love the Lottery Mentality: Human beings are naturally drawn to small chances of big rewards. It’s the same reason people buy lottery tickets. A longshot bet offers a “risk a little, win a lot” scenario, which our brains find very tempting. The possibility of a huge payday overshadows the tiny probability of it happening. In psychology, this is linked to prospect theory – we tend to overweight small probabilities and get overly optimistic about unlikely outcomes. In simple terms, we think that a 1% chance might happen more often than it really will. That leads us to overestimate the underdog’s shot at winning.
- Misjudging the Odds: Many bettors aren’t great at assessing true probabilities, especially when the odds are long. A team at 20-to-1 odds sounds like it has a chance (“Hey, 20-to-1 – not impossible, right?”), but in reality that’s just a 5% implied chance of winning. We struggle to grasp how low 5% is, often believing the underdog is more capable of an upset than the math supports. This inaccurate estimation of unlikely events fuels the bias.
- Thrill-Seeking and Storytelling: Betting is not only about logic; it’s also entertainment. Cheering for a longshot can be more fun. There’s a thrill in saying “I called the upset!” Some bettors are risk-loving by nature – they enjoy the gamble itself and the adrenaline of a big payoff. Others might get caught up in the narrative (e.g., “This could be the next Miracle on Ice!”). Taking a flyer on a longshot makes for a great story if it hits. Favorites, on the other hand, are expected to win – there’s less glory in picking the obvious choice, even though it’s the more likely outcome.
- Fear of Missing Out: There’s a bit of FOMO at play too. When you see a longshot at huge odds, you might think, “What if they actually win and I didn’t bet it? I’d kick myself for missing out!” Bookmakers set tantalizing odds on parlays and longshots precisely because they know this fear can nudge you into a wager. It’s hard to watch a 100-to-1 underdog win and not think “If only I had put $10 on that…”. So people toss money on low-probability bets “just in case,” even though it’s usually a poor strategy long-term.
In summary, our brains are wired to misjudge risk and reward in betting. We overweight the unlikely big win and under-appreciate the steady, smaller win. This psychological trap is a big reason the favorite-longshot bias exists.
How Bookmakers Take Advantage of the Bias
It’s not just bettors’ minds contributing to this bias – bookmakers know about it and adjust the odds accordingly. Sportsbooks are in business to make money, and they’ve noticed that casual bettors love longshots.
So what do they do? They bake extra profit margin into longshot odds.
Here’s how it works: A bookmaker always includes a “vig” or house edge in the odds (that’s how they ensure a profit).
But they don’t spread that edge evenly. They often load more of the vig onto the longshots.
Why? Because they can get away with offering worse odds on longshots – people will still bet on them for the reasons above.
For favorites, if the book made the odds too unattractive, bettors might pass, so the book keeps those odds a bit fairer. But for a 50-to-1 underdog, the bookie isn’t as worried about offering a bad price; the allure of a big payout is enough to draw bets even if the odds are slightly stingy.
In practical terms, this means the true odds of a longshot are often higher than what you’re being paid. The bookmaker is erring on the side of caution. They shorten the odds on longshots “just in case” that unlikely event comes through, to limit their own payout.
As a result, if you blindly bet longshots, you’re paying a premium for those bets (and thus getting poorer value).
On the flip side, odds on favorites can sometimes be a smidge more generous relative to true probability, because the book doesn’t need to pad those as much. The outcome of this practice is the same: longshot bettors face a steeper uphill battle.
So between human nature and bookmaker odds-setting, the deck is stacked against longshots. Bettors keep taking them at bad prices, and the cycle continues.
A research analysis put it plainly: if you bet without thinking, you’ll lose money overall, but you’ll lose less betting on favorites than betting on longshots. The bias doesn’t mean favorites always win (they don’t), it just means the odds for favorites are usually a better reflection of reality, while longshot odds are often a fantasy.
Real-Life Examples of the Favorite-Longshot Bias
This bias might sound abstract, but you’ve probably seen it in action. Let’s look at a couple of relatable examples across different sports:
- Horse Racing: The classic example. Suppose you’re at the track and every casual bettor is throwing $2 on the longest shot in the race because “why not, it pays 100-1!”. After all the bets, the tote board might show that rank outsider at 50-1 by post time (because so many people bet it down from 100-1). Meanwhile, the odds-on favorite might drift from 2-1 out to 3-1 because everyone is ignoring the boring pick. When the race runs, favorites win a lot more often than those longshots. Over many races, the favorite-backers lose a small amount of money (due to the takeout), but longshot-backers lose a ton. It’s common to see the public overbet the longshots, creating overlays on favorites. The racetracks/bookmakers have no issue with this – they count on underdog enthusiasts to boost their profits.
- Big Sports Upsets: Think of a huge underdog team in March Madness, or a low-seeded player in a tennis Grand Slam facing a champion. The sportsbook might list the underdog at +1000 (10-to-1) and the favorite at -1500. Casual fans see +1000 and go “Hey, $20 wins $200, let’s roll the dice!”. The favorite might be the far smarter bet to win, but it feels expensive (you’d have to risk $150 just to win $10 at -1500). So money trickles in on the longshot. If that underdog wins, the book pays out some happy bettors – but those upsets are rare. More often, the favorite wins (as expected), and all those longshot bets become donations to the book’s coffers. Over the whole season, those who consistently backed big underdogs will have a worse return than those who backed favorites, illustrating the bias. As one analysis put it, betting favorites produces higher long-term returns (still often negative, but closer to break-even) than betting longshots across many sports.
- Parlay Bets: Parlays are the ultimate longshot temptation for many bettors. Stringing together multiple outcomes for a massive payout – it’s fun, but the odds of hitting are slim. Each added leg is like another longshot multiplied in. Bettors love parlays (who doesn’t fantasize about a $10 parlay turning into $10,000?). Sportsbooks love them too, because the hold (profit margin) on parlays is huge. This is favorite-longshot bias on steroids – people voluntarily take extremely long odds for the lottery-like reward. Have you noticed sports betting ads always tout the one big parlay win someone had? That’s because it’s an outlier. For every one of those, thousands of parlays (and longshot bets) quietly lose. The bias lives in those bets: the excitement of a longshot win clouds the fact that the odds are stacked against the bettor.
In short, any time you see bettors flocking to a high-odds outcome just because “it would be awesome if it hits,” you’re seeing the favorite-longshot bias at work. Favorites win more than we give them credit for, and longshots win less than we hope.
Using the Favorite-Longshot Bias to Bet Smarter
Okay, so the deck is stacked. Does that mean you should never bet an underdog or longshot? Not exactly. But it does mean you should be selective and value-conscious when you do. Here’s how you can use this knowledge to make smarter bets:
1. Don’t Fall in Love with the Payout: Before placing a bet, ask yourself honestly – am I betting this because I think it’s a likely winner, or just because the payout looks attractive?
If it’s purely the payout, that’s the bias talking. Step back and assess the true chance of the bet.
For example, a team at +1000 might be nowhere near a 10% chance to win in reality; if you think their real chances are more like 3-5%, +1000 isn’t a good deal. Chasing long odds for the thrill is a quick way to burn through money.
2. Look for Value in Favorites: This might sound un-sexy, but often the best value bets are on favorites or moderate favorites that the public is neglecting. Since many casual bettors avoid low-paying favorites, sometimes the odds on a favorite can be better than they “should” be (especially in less popular markets or niche sports). If you’ve done your homework and believe a favorite has, say, an 80% chance to win, but the odds imply only 70%, that’s a value bet.
Don’t be afraid to bet favorites — the data shows they tend to offer higher expected returns than comparable longshots. You’re not a sucker for betting the favorite; you’re being savvy by not falling for an overpriced longshot.
3. Be Picky with Longshots: This bias doesn’t mean longshots never win or that there’s no time to bet on an underdog. Upsets happen and sometimes the market truly underestimates an underdog (e.g., maybe a star player is injured but the public hasn’t caught on, etc.).
The key is to identify when a longshot is genuinely undervalued, not just bet every big odds play that comes along. If you can pinpoint a scenario where you believe the true odds of the “longshot” are better than what the bookmaker is offering, that’s a smart longshot bet.
Just know these situations are rarer than people think. If you’re taking a longshot, make sure you have a solid reason beyond “it would be nice if it wins.”
4. Manage Your Bankroll (Don’t Swing for the Fences Every Time): Because longshots are so appealing, bettors sometimes risk too much on them. They swing for a home run and forget about the consistent singles and doubles. Always practice good bankroll management – that means usually wagering a modest, fixed percentage of your bankroll on any given bet.
If you do take a flyer on a big underdog, keep the stake sensible. Remember, favorites and underdogs alike should be part of a balanced strategy. Don’t load up all on one side. The bias tells us the average longshot is a bad bet, so maybe they should make up only a small portion of your betting portfolio, unless you have strong info or insight.
5. Learn from the Bias – Find the Sweet Spot: Some research suggests the bias is strongest on the extreme longshots. For moderate underdogs, the bias might be smaller. This implies that the most skewed bets (the 100-to-1 moonshots) are the worst deals, whereas a smaller underdog (+300, +400, etc.) might not be as heavily biased.
There might even be cases where public bias flips (for example, in very high-profile games, sometimes the favorite is overbet and an underdog might become a value – though that’s often more about point spreads).
The takeaway: know that the bias isn’t uniform. Use it to avoid the really bad bets (tiny probability, huge payout, huge house edge) and to scout for instances where a favorite might be a bargain.
Wrapping Up: Keep a Balanced Perspective
The favorite-longshot bias teaches an important betting lesson: glamour doesn’t equal profit. The bets that make you daydream (15-leg parlays, miracle underdogs, lottery ticket odds) are usually the ones with the worst expected returns.
The steady, workmanlike approach of finding value – often in favorites or evenly matched games – might not make for Hollywood stories, but it’s more likely to grow your bankroll over time.
Next time you’re about to bet on a longshot, remember this conversation. Picture two bettors: one always swings for the fences with longshots, and the other mostly sticks to logical favorites and value plays.
Over a season, the second bettor often comes out ahead (or at least loses less). The first bettor has great stories of “almost hits,” but an emptier wallet. Don’t be the bettor donating money on long odds just for a thrill. There’s nothing wrong with taking an underdog – just make sure you’re doing it for the right reasons and at the right price.
In the end, understanding the favorite-longshot bias is one more tool in your arsenal. It can save you from making impulsive bets on bad odds and help you spot opportunities others might ignore.
Sports betting is all about finding an edge, and sometimes that edge is simply avoiding a common mistake. So the next time a 100-to-1 longshot catches your eye, you can smile, recognize why it’s tempting, and then make the smart call for your bankroll.
Happy betting, and may your picks be valuable – not just bold!
