Betting on Favorites vs Underdogs: Strategy, Math & When to Use Each

Understanding when to bet favorites versus underdogs is one of the most important skills in sports betting. Favorites offer higher win rates but lower payouts. Underdogs offer higher payouts but win less often. The key is knowing which side offers value in each situation.

This guide explains the math behind favorites and underdogs, when to bet each, common mistakes to avoid, and sport-specific strategies for NFL, NBA, and MLB betting. You will learn how to evaluate risk versus reward and identify value opportunities on both sides of the market.

21+ only. Bet responsibly and only with money you can afford to lose.

How Odds Define Favorites and Underdogs

In American odds, favorites have negative numbers and underdogs have positive numbers.

Reading Favorite Odds (Negative Numbers)

Negative odds tell you how much you must risk to win 100 dollars in profit.

Example: -200

You risk 200 dollars to win 100 dollars profit. Your total return is 300 dollars (your 200 dollar stake plus 100 dollars profit).

The bigger the negative number, the heavier the favorite. A team at -400 is a bigger favorite than a team at -150.

Reading Underdog Odds (Positive Numbers)

Positive odds tell you how much profit you win from a 100 dollar stake.

Example: +200

You risk 100 dollars to win 200 dollars profit. Your total return is 300 dollars (your 100 dollar stake plus 200 dollars profit).

The bigger the positive number, the bigger the underdog. A team at +300 is a bigger underdog than a team at +150.

What Makes a Team a Favorite or Underdog?

Sportsbooks set odds based on:

• Team strength and recent performance
• Home field advantage
• Injuries and roster availability
• Public betting sentiment
• Sharp money movement
• Weather and game conditions

The favorite is the team more likely to win. The underdog is the team less likely to win. Odds reflect the sportsbook assessment of win probability, adjusted for vig.

For a full explanation of moneyline odds, see our Moneyline Betting Guide.

The Math: Risk vs Reward with Favorites and Underdogs

The fundamental trade-off in favorites versus underdogs is risk versus reward.

Favorite Math: High Win Rate, Low Payout

Example: Team at -200 (66.7% implied probability)

• You risk 200 dollars to win 100 dollars profit
• If you win, your return on investment is 50% (100 profit on 200 risked)
• If you lose, you lose your full 200 dollar stake

To break even betting only -200 favorites, you need to win more than 66.7% of the time. That is the implied probability.

Formula for breakeven win rate on favorites: Breakeven = absolute value of odds / (absolute value of odds + 100)

Example: -200 = 200 / (200 + 100) = 66.7%

Underdog Math: Low Win Rate, High Payout

Example: Team at +200 (33.3% implied probability)

• You risk 100 dollars to win 200 dollars profit
• If you win, your return on investment is 200% (200 profit on 100 risked)
• If you lose, you lose your 100 dollar stake

To break even betting only +200 underdogs, you need to win more than 33.3% of the time.

Formula for breakeven win rate on underdogs: Breakeven = 100 / (odds + 100)

Example: +200 = 100 / (200 + 100) = 33.3%

Comparing Equal-Risk Scenarios

If you bet 100 dollars on a -200 favorite, you win 50 dollars profit. If you bet 100 dollars on a +200 underdog, you win 200 dollars profit.

The favorite needs to win twice as often as the underdog to break even on equal stakes. But the underdog pays four times as much profit per 100 dollars risked.

This is why value matters more than win rate. A 35% underdog at +200 is profitable long-term, even though it loses 65% of the time.

When to Bet Favorites (Situations and Strategy)

Betting favorites makes sense in specific situations where the favorite is underpriced or offers strategic value.

1. Short Favorites with Strong Edge

Short favorites (around -110 to -150) can offer value when you have a strong opinion on the outcome.

Example: Team is -130 (56.5% implied probability) but you assess their true win probability at 65%. This is a value bet even though you are laying juice.

Short favorites balance win rate and payout better than heavy favorites. You still get reasonable odds without needing to risk massive amounts.

2. Heavy Favorites in Lopsided Matchups

Heavy favorites (around -250 to -400) make sense when the matchup is truly lopsided and you want near-certainty.

Example: NBA superteam at home against a tanking team missing key players. The favorite may be -350, but the true win probability might be 85% or higher.

Risk: Even heavy favorites lose. One upset wipes out multiple wins. Only bet heavy favorites when the edge is clear and large.

For more on when to use favorites versus spreads, see our Moneyline vs Spread Guide.

3. Live Betting Favorites After Adversity

In-game, a favorite that falls behind early may see their odds lengthen. If you believe the early deficit is variance (not indicative of true strength), the favorite offers value.

Example: NFL favorite is -200 pre-game. They fall behind 7-0 in the first quarter due to a turnover. Live odds shift to -120. If you believe the turnover was unlucky and the favorite is still the better team, the live -120 offers better value than the pre-game -200.

4. Parlaying Multiple Favorites for Higher Payout

Parlays combine multiple favorites to increase payout. A three-leg parlay of -150 favorites pays roughly +387 if all three win.

Risk: All legs must win. One loss kills the ticket. Parlays are high-variance and reduce your edge on each individual bet. Use sparingly.

For parlay strategy, see our Parlay Betting Guide.

5. Bankroll Preservation (Lower Variance)

Favorites lose less often than underdogs. If you want to reduce variance and preserve bankroll, betting favorites smooths your results over time.

This does not mean favorites are always profitable. You still need an edge. But for bettors who prefer steadier returns and can accept lower payouts, favorites reduce swings.

When to Bet Underdogs (Value Opportunities)

Underdogs offer higher payouts and can be more profitable long-term if you identify value.

1. Overvalued Favorites Create Underdog Value

Public betting often inflates favorite prices. When the public loads up on a popular team, the underdog price lengthens, creating value.

Example: Popular NFL team is -180 (64.3% implied probability). You assess their true win probability at 58%. The underdog at +160 (implied 38.5%) may have a true probability of 42%, offering positive expected value.

Line shopping helps you find the best underdog price. For more on finding value, see our Moneyline Betting Strategy Guide.

2. Underdogs with Situational Edges

Certain situations favor underdogs:

NFL: Home underdogs in division games, underdogs off a bye week, underdogs in weather games (wind, rain, cold)

NBA: Underdogs on rest advantages (rested vs back-to-back opponent), underdogs with key players returning from injury

MLB: Underdogs with ace starting pitchers, underdogs in day games after night games, underdogs in pitcher-friendly parks

Situational edges do not guarantee wins, but they shift true probability higher than the implied probability suggests.

3. Big Underdogs in High-Variance Sports

Sports with high variance (like baseball and hockey) see more underdog wins than lower-variance sports (like basketball).

In MLB, even bad teams win 40% of their games. A +200 underdog (33.3% implied probability) may have a true probability of 38%, offering value.

In NBA, the best teams dominate bad teams consistently. A +200 NBA underdog may truly have only a 28% chance to win, making it a bad bet.

Underdog value is sport-specific. Always consider the variance of the sport when evaluating underdog bets.

4. Live Betting Underdogs After Early Success

If an underdog jumps out to an early lead, the favorite odds shorten and the underdog odds lengthen. You can hedge by betting the favorite live, or double down on the underdog if you believe their early success reflects true strength.

Example: MLB underdog is +150 pre-game. They score 3 runs in the first inning. Live odds shift to +110. If you believe the early runs reflect good lineup matchups (not luck), the +110 offers less value than the pre-game +150, but still may be profitable.

5. Round Robin and Underdog Parlays for Lottery Ticket Value

Round robins and underdog parlays offer massive payouts if multiple underdogs hit. A three-leg underdog parlay at +150 each pays roughly +1287.

Risk: Variance is extreme. Most tickets lose. This is entertainment betting, not disciplined strategy. Allocate only a small portion of your bankroll to these bets.

Common Mistakes Betting Favorites and Underdogs

1. The Favorite Trap: Chasing Short-Term Results

Betting favorites feels safe because they win more often. But if the favorite is overpriced, you lose money long-term.

Example: Betting every -200 favorite without assessing value. If your true win rate is 65% (below the 66.7% breakeven), you bleed money slowly.

Solution: Only bet favorites when you assess their true win probability is higher than the implied probability. Value matters, not just win rate.

2. Chasing Big Underdogs Without Edge

Betting big underdogs (+300 or higher) is tempting because of the payout. But if the underdog truly has only a 15% chance to win and the implied probability is 25%, you are betting negative expected value.

Solution: Only bet underdogs when you believe their true win probability is higher than the implied probability. Big payouts do not equal good bets.

3. Ignoring Context and Betting Blindly by Role

Not all favorites are good bets. Not all underdogs are bad bets. Each game is unique.

Example: Blindly betting all home favorites in the NFL without considering injuries, weather, or matchup dynamics. You will win often but lose money if the prices are inflated.

Solution: Evaluate each game individually. Use situational analysis, injury reports, and matchup data to assess true probability.

4. Mixing Favorite and Underdog Strategies Inconsistently

Some bettors bet favorites one week and underdogs the next based on gut feel. This leads to inconsistent results and makes it hard to track edge.

Solution: Define your strategy. Are you a value bettor (betting both sides when you find edge)? A favorite bettor (lower variance, steady returns)? An underdog bettor (higher variance, hunting plus-money)? Stick to your approach and track results.

5. Overreacting to Short-Term Variance

Favorites lose. Underdogs win. Variance is normal. A losing streak on favorites does not mean the strategy is broken. A winning streak on underdogs does not mean you found a magic formula.

Solution: Track your results over at least 100 bets. Use a large enough sample to see if your edge is real or if results are noise.

Sport-Specific Favorite and Underdog Strategy

NFL: Favorites and Underdogs by Spread

In the NFL, favorites and underdogs behave differently based on the point spread.

Short spreads (1 to 3 points): Games are close. Moneyline favorites are often overpriced. Consider the underdog or the spread.

Medium spreads (4 to 7 points): Favorites win about 65-70% straight up. Moneyline value depends on price. Compare moneyline odds to spread odds.

Large spreads (8+ points): Heavy favorites. Evaluate whether the moneyline or spread offers better value. Often the spread is safer.

Home underdogs in the NFL perform better than road underdogs. Division underdogs also perform well due to familiarity.

NBA: Favorites Dominate, Underdogs Rare Value

The NBA is a low-variance sport. Favorites win at a high rate, especially at home.

Heavy favorites (-300 or more) in the NBA win around 80-85% of the time. This is higher than most other sports.

Underdog value in the NBA comes from:

• Rest advantages (team on rest vs team on back-to-back)
• Key player returns from injury
• Playoff-bound underdogs vs non-playoff favorites late in season
• Live betting when underdog jumps to early lead

Blindly betting NBA underdogs is a losing strategy. Only bet underdogs with clear situational edge.

MLB: Underdog Paradise (High Variance)

Baseball is the highest-variance major sport. Even bad teams win 40% of games.

Starting pitchers drive moneyline odds. A +150 underdog with an ace pitcher may offer value if the favorite has a weak starter.

First five innings (F5) moneylines reduce variance by eliminating bullpen randomness. Use F5 moneylines when betting favorites or underdogs based on starting pitching.

MLB underdogs offer more value than underdogs in most other sports. Look for:

• Underdog aces vs favorite mid-rotation starters
• Home underdogs in pitcher-friendly parks
• Day game underdogs after night games (rest advantage)

For more on MLB betting, see our MLB guide (coming soon).

Bankroll Management for Favorites vs Underdogs

Unit Sizing for Favorites

Betting favorites requires larger stakes to win meaningful profit. A -200 favorite requires you to risk 200 dollars to win 100 dollars.

Recommendation: Risk 1 to 2 units on short favorites (-110 to -150). Risk 0.5 to 1 unit on heavy favorites (-200 or more).

Never risk more than 5% of your bankroll on a single favorite, no matter how confident you are. Upsets happen.

Unit Sizing for Underdogs

Underdogs pay more profit per unit risked. You can risk smaller amounts and still earn meaningful profit.

Recommendation: Risk 0.5 to 1 unit on small underdogs (+100 to +200). Risk 0.25 to 0.5 units on big underdogs (+200 or more).

Because underdogs lose more often, you need a larger bankroll cushion to survive losing streaks. Budget for variance.

Tracking Results by Role

Track your favorite bets and underdog bets separately. This helps you see where your edge is.

Example tracking table:

Bet Type	Record	Units Won/Lost	ROI
Favorites (-110 to -150)	45-20	+8.2 units	12.6%
Heavy Favorites (-200+)	20-5	+2.1 units	8.4%
Underdogs (+100 to +200)	25-35	+4.5 units	7.5%
Big Underdogs (+200+)	8-22	-3.2 units	-10.7%

This shows you where you have edge and where you are leaking profit.

For more on bankroll management, see our Moneyline Betting Strategy Guide.

Use Our Free Moneyline Calculator

Calculate your potential payout and implied probability for any favorite or underdog bet. Enter your stake and odds to see how much you can win.

This tool shows math, not predictions. Always gamble responsibly and only bet what you can afford to lose.

For a full calculator guide, see our Moneyline Calculator Guide.

Frequently Asked Questions

Is it better to bet favorites or underdogs?

Neither is inherently better. Favorites win more often but pay less. Underdogs win less often but pay more. The best bet is the one with positive expected value, whether favorite or underdog.

What is the favorite trap in sports betting?

The favorite trap is when bettors assume favorites are safe bets because they win often. If the favorite is overpriced (implied probability higher than true probability), you lose money long-term despite a high win rate.

Do underdogs win more often in certain sports?

Yes. High-variance sports like baseball and hockey see more underdog wins than low-variance sports like basketball. MLB underdogs offer more value than NBA underdogs.

How often do heavy favorites lose?

Heavy favorites (around -300 to -400) lose roughly 20-25% of the time across most sports. Even -1000 favorites lose occasionally. No bet is guaranteed.

Should I always bet against the public on favorites?

Not always. Public betting often inflates favorite prices, creating underdog value. But if the favorite is legitimately strong and the price is fair, betting against the public just because they are on the favorite is a bad strategy. Evaluate each game individually.

Can I make money only betting favorites?

Yes, if you consistently find value favorites where the true win probability is higher than the implied probability. You need an edge, not just a high win rate.

Can I make money only betting underdogs?

Yes, if you consistently find value underdogs where the true win probability is higher than the implied probability. Underdog betting requires a larger bankroll to survive variance.

What is a good win rate for favorite bettors?

For short favorites (around -150), you need to win at least 60% to break even. A good win rate for profitable favorite betting is 63-65% or higher, depending on the average odds.