What is Positive EV (+EV)? The Smart Bettor's Guide to Long-Term Profits

You just lost a bet on Patrick Mahomes Over 249.5 passing yards.

He threw for 247 yards—three yards short. You're frustrated. You did your research. You watched the highlights. The matchup looked good on paper, and you truly thought it would hit.

Here's the thing: you might have made the right bet even though you lost. This is the power of positive EV betting—a concept that transforms how you approach sports wagering.

Wait, what?

Welcome to the world of Positive Expected Value betting—the mathematical framework that separates the 2-3% of profitable sports bettors from everyone else. It's not about picking winners. It's about finding bets where the math is on your side.

Let's break this down.

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The Problem With "Picking Winners"

Most bettors approach sports betting like this:

1. Look at a matchup
2. Decide who's going to win (or hit their prop)
3. Bet on that outcome
4. Hope for the best

This is gambling. And over time, the house wins.

Why? Because sportsbooks aren't in the business of predicting outcomes—they're in the business of setting odds that guarantee them a profit regardless of who wins. That built-in margin (called the "vig" or "juice") means that even if you pick winners 50% of the time, you're still losing money.

At standard -110 odds, you need to win 52.4% of your bets just to break even.

Most bettors don't. According to industry data, sportsbooks won at a 9.3% rate nationally in 2025. That's not because sportsbooks are smarter than you—it's because most bettors are asking the wrong question.

Instead of asking "Who's going to win?" you should be asking "Is this bet priced correctly?"

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What is Expected Value (EV)?

Expected Value is a math concept that tells you how much you can expect to win (or lose) on average per bet over the long run.

Here's the formula:

EV = (Probability of Winning × Amount Won) − (Probability of Losing × Amount Lost)

Important: "Amount Lost" is the amount you're risking, which at -110 odds is $110 to win $100.

If the EV is positive, the bet is mathematically in your favor. If it's negative, the house has the edge. Understanding expected value is the foundation of finding your betting edge.

Let's make this concrete with a simple example.

The Coin Flip Test

Imagine someone offers you this bet:

• Bet: $100 on a coin landing heads
• Payout if you win: $120 profit
• True probability of heads: 50%

Let's calculate the EV:

EV = (50% × $120) − (50% × $100)
EV = $60 − $50
EV = +$10

That's a +10% edge. Even though you'll lose half the time, the payout when you win more than compensates for your losses. Over 100 flips, you'd expect to profit around $1,000.

This is positive expected value in its purest form.

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Positive EV vs. Negative EV: A Real Example

Let's look at two different Ja Morant points props and see why one is a solid bet and one is a trap—even though both might "look good" on paper.

Same player, same game, completely different value. The "worse" odds (-105) are actually the better bet because the probability of winning is much higher than the sportsbook implies.

Breaking Down the Good Bet

At -105 odds, the sportsbook is implying a 51.2% probability that Ja goes over 22.5 points.

But based on his season average (23.2 PPG), his hit rate on this line (68%), and the favorable matchup against Utah's weak perimeter defense, the actual probability is closer to 65%.

The gap between 65% (our projection) and 51.2% (their implied probability) is the edge.

Edge Calculation:
Implied Probability: 51.2%
True Probability: 65%
Edge: 65% - 51.2% = +13.8%

Expected Value (EV) Calculation:
EV = (65% × $100) − (35% × $105)
EV = $65 − $36.75
EV = +$28.25 per $105 risked

This represents a +13.8% probability edge, which translates to a return on investment (ROI) of +26.9%. Both numbers are telling you the same thing: this is a strong bet with significant value.

Breaking Down the Bad Bet

The Over 28.5 at +120 looks appealing—plus money on a star player! But the math tells a different story.

At +120 odds, the sportsbook is implying a 45.5% probability. But Ja only hits 28+ points about 32% of the time.

The sportsbook is actually being more generous than they should be—because they know casual bettors love plus-money star player props.

Edge Calculation:
Implied Probability: 45.5%
True Probability: 32%
Edge: 32% - 45.5% = -13.4%

Expected Value (EV) Calculation:
EV = (32% × $120) − (68% × $100)
EV = $38.40 − $68
EV = −$29.60 per $100 risked

This represents a -13.4% probability edge against you, which translates to an ROI of -29.6%. This is a terrible bet, despite the attractive plus-money odds.

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Why Most Bettors Get This Wrong

Here's what a typical bettor sees:

Bet	Odds	Typical Thinking
Ja O 22.5 Pts	-105	"Meh, I have to risk $105 to win $100. Boring."
Ja O 28.5 Pts	+120	"Ooh, plus money! I can win $120 on a $100 bet. This could hit."

They chase the bigger payout and ignore the actual probability. This is exactly what sportsbooks are counting on. Understanding positive EV means looking beyond the surface-level odds to find mathematical value.

The lesson: Plus-money odds aren't automatically good, and minus-money odds aren't automatically bad. What matters is whether the true probability justifies the price.

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How Do You Find the "True Probability"?

This is where it gets interesting—and where most bettors give up.

Finding +EV bets requires estimating the actual probability of an outcome more accurately than the sportsbook. That means analyzing data most casual bettors ignore:

• Head-to-head performance: How has this player performed against this specific opponent? Season averages can be misleading if a player consistently dominates (or struggles against) certain teams.
• Opponent defense rankings: Is the player facing a top-tier defense or one that's been getting torched all season?
• Usage trends: Is this player's role expanding or shrinking? A guy whose snap count jumped 15% over the last two weeks is seeing more opportunities.
• Recent form: Is the player hot or cold? Streaks matter more than most people think.
• Game context: Pace of play, home/away splits, rest days, injury reports—all of it affects probability.
• Weather conditions: For outdoor sports, wind and precipitation can tank passing props and boost rushing numbers.
• Line movement: Where did the line open vs. where is it now? Sharp money often moves lines before the public catches on.

TrueEdge analyzes 10 key factors across thousands of props to calculate edge:

1. Head-to-head performance: How has this player performed against this specific opponent?
2. Opponent defensive ranking: Both overall defensive rating and position-specific defense
3. Recent usage trends: Is the player's role expanding or shrinking over the last 10 games?
4. Current form: Hot streaks and cold streaks matter—recent efficiency often predicts near-term performance
5. Game context: Pace of play, projected game total, and game script expectations
6. Rest & schedule: Back-to-backs, travel, days of rest—fatigue affects performance
7. Home/away splits: How does the player perform in this environment?
8. Weather conditions: For outdoor sports (NFL, MLB), wind and precipitation significantly impact props
9. Line movement: Where sharp money is going vs. where public money is going
10. Injury reports & player news: Real-time information that affects projections

The goal isn't to be right every time—it's to consistently find situations where the math favors you.

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+EV Betting is a Long Game

Here's something that trips up beginners: you can make a +EV bet and still lose.

That Ja Morant Over 22.5 bet with a 65% win probability? It loses 35% of the time. You might bet it five times and lose three of them. That's variance, and it's completely normal.

The key is discipline: Positive EV betting requires patience, but the math guarantees profits over time.

1. Focus on the process, not individual outcomes. If you're consistently betting +EV, profits will come over time.
2. Track everything. You need data to know if your edge is real. Write down every bet, the edge you calculated, and the result.
3. Size your bets appropriately. Even +EV bets can lose, so don't bet your entire bankroll on one play. Most pros bet 1-3% of their bankroll per bet.
4. Ignore the noise. Your buddy who "just knows" the Chiefs are going to cover isn't using math. You are.

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The Difference Between Gambling and Investing

Casual bettors are gambling. They're hoping to get lucky.

+EV bettors are investing. They're playing a numbers game where math is on their side.

It's the same principle as the stock market. You don't need every stock to go up—you need your portfolio to outperform over time. Individual losses don't matter if the strategy is sound.

The 2-3% of sports bettors who actually profit long-term? They all understand expected value. They all bet on math, not hunches. They all have the discipline to stick to their process even during losing streaks.

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How TrueEdge Helps You Find +EV Bets

Most +EV betting requires hours of manual research—comparing odds across sportsbooks, pulling player stats, calculating probabilities by hand. It's tedious, and most people don't have the time.

TrueEdge does the heavy lifting for you. Our AI-powered algorithm analyzes thousands of props to surface the best +EV opportunities.

• We analyze thousands of props weekly across NFL, NBA, MLB, and NHL
• Our AI evaluates 10 key factors for every prop—H2H matchups, defensive rankings, usage trends, and more
• We show you the edge on each bet, not just a recommendation
• We explain why in plain English—like your sharp friend texting you, not a spreadsheet

The result? You see a curated list of the day's best +EV opportunities, ranked by edge, with clear explanations of what makes each bet valuable.

No guessing. No research rabbit holes. Just math-backed insights delivered simply.

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The Bottom Line

Positive Expected Value betting isn't about being "right" on every bet. It's about consistently finding situations where the math favors you—and having the discipline to let that edge compound over time.

Key takeaways:

1. Stop asking "who will win?" Start asking "is this priced correctly?"
2. Plus-money odds aren't automatically good. A 32% chance at +120 is worse than a 65% chance at -105.
3. Focus on factors that move probability: H2H performance, defense matchups, usage trends, recent form, and more.
4. Track your results. The only way to know if you have an edge is to measure it.
5. Stay disciplined. Individual losses are noise. The process is the signal.

The sportsbooks aren't smarter than you. They just have better math. Once you understand +EV betting, the next step is learning how to consistently find and calculate your edge on every bet you make.

For a detailed breakdown of how much edge you need to make profitable bets, check out our guide on what edge means in sports betting.

Now you can too.

Want to see how TrueEdge calculates edge for every prop? Learn how our 10-factor analysis works.

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Frequently Asked Questions About +EV Betting

Q: What does positive EV mean in sports betting?
A: Positive EV, also called +EV or positive expected value, means a bet has a mathematical advantage in your favor. It's when the true probability of winning is higher than what the sportsbook's odds imply. Over many bets, consistent +EV betting leads to long-term profit.

Q: How do I calculate expected value for a bet?
A: Use this formula: EV = (Probability of Winning × Amount Won) − (Probability of Losing × Amount Lost). If the result is positive, it's a +EV bet. For example, a 60% chance to win $100 versus a 40% chance to lose $110 equals +$16 expected value.

Q: Can you have positive EV and still lose a bet?
A: Yes, absolutely. A +EV bet might have a 65% chance of winning, but that means it loses 35% of the time. Individual losses are completely normal and expected. What matters is that consistent +EV betting leads to long-term profit over hundreds of bets.

Q: What's the difference between +EV and -EV bets?
A: +EV bets have the math on your side—the true probability of winning is higher than the odds imply. -EV bets have the math against you—the sportsbook has an edge over you. Even at attractive plus-money odds, a bet can be -EV if the actual probability is too low.

Q: Is +EV betting the same as arbitrage betting?
A: No, they're different strategies. Arbitrage betting involves betting both sides of an outcome across different sportsbooks to guarantee profit regardless of result. +EV betting means finding individual bets where the math favors you long-term, without needing to hedge.

Q: Do sportsbooks ban positive EV bettors?
A: Sharp bettors who consistently win can face betting limits or account restrictions from some sportsbooks. However, most recreational +EV bettors don't bet large enough amounts to trigger these measures. Using multiple sportsbooks helps mitigate this risk.

Want to learn more about finding edge? Check out our guide on What is 'The Edge' in Sports Betting.