Positive EV Betting (Positive Expected Value)

The odds of a coin flip are 50/50. The true odds of wagering on heads or tails are written as even money (+100). Most sporting event outcomes are also 50/50, although there are ties in soccer and sometimes even in the NFL. But oddsmakers don't put +100 on each side of a game, or they wouldn't be able to take a cut after paying out the winners. That's why they make it -110, -115, or -120, forcing a bettor to lay $115 -115 on a game to win $100. Theoretically, betting on tails would have a positive expected value if they made a coin flip -115 on heads and +115 on tails. A sports bettor would expect to win with tails 50% of the time, but is getting plus money (+115).

The calculation works like this:

Expected Value = (Probability of Winning, 50% or 0.5) x (Amount Won) minus (Probability of Losing, 50% or 0.5) x (Amount Lost) 

EV = 0.5 x $115 - 0.5 x $100 

EV = $57.50 - $50

Expected Value = $7.50

The expected value of this bet is $7.50. Therefore, this would be a 7.5% positive expected value opportunity, as $7.50 is 7.5% of your $100 wager. One of the best ways to consistently beat the closing line is to find positive expected value bets. 

Here are a few different ways of finding positive EV bets including using EV betting tools.

Sports Betting Projections-Based Model

Projections-based modeling is one route that helps find +EV bets and it can help you too. For instance, ESPN broadcasts projections of expected winners on marquee sports events all the time. They use computer modeling based on three years of player stats and team production, emphasizing recent performance. ESPN's computer model gave the Eagles a 56.1 percent chance of defeating the Chiefs in the 2025 Super Bowl. That turned out to be correct as Philadelphia won, 40-22. The Eagles opened at +110 on the moneyline and closed at +104 as more money came in on the underdog to win the game. Bettors agreeing with their model grabbed more positive value at +110 before the line moved to +104. The good thing about models is that one can use hard data or tinker with specific stats based on what adjustments a bettor thinks need to be made. That introduces personal bias, but oddsmakers do that when making certain lines, such as giving an edge to public teams or overreacting to a team after a surprising blowout win or loss in the previous week. Other models place a heavier emphasis on home play and recent head-to-head matchups.

Market-Based Model

Another way to gauge positive expected line value is by letting the betting market decide. Market-based models aren't interested in statistical matchups but revolve around the notion that line movement best reflects what teams the betting sharps are on. 

It's similar to the stock market and day traders. 

For instance, if a football or basketball total moves 2 or 3 points, that's a sign that a string of respected bettors have pounced on a weak number. Sharp bettors would quickly search for books that have yet to adjust their totals. Any book offering the direction the sharp bettor wants (OVER or UNDER) at greater than even-money odds (+105, +110) would be a positive EV bet. These sharp bettors aren't interested in statistical game analysis but react to betting market indicators. 

Arbitrage Betting 

Another form of positive EV wagering is Arbitrage Betting, also called "Arbing" or "Sure Betting". Instead of putting the odds in your favor to win one wager, you're locking in both sides of the same game with two bets to guarantee a small profit. Sportsbooks will have different odds with lines shifting during the day and the week. For instance, if one sportsbook is offering odds of +120 on the NY Giants to win on the moneyline against Dallas, and the Cowboys are at minus-105 at another book, you could wager $200 on the Giants (+120) to win $240, and $225.50 on the Cowboys to win $214.76. You're guaranteed to win one bet and lose the other, locking in a profit of almost $15 and increasing your bankroll. The outcome of the game doesn't matter. 

Pro tip for this approach: The more books you can visit or play online, the greater your chances of finding the right moneyline differential to lock in a positive EV bet.

Value Betting

The odds of winning games like blackjack, craps, and slot machines can be numerically calculated. Casinos know those figures and compute payouts. By law, all video lottery games must return between 87% and 95%, while a blackjack table hold percentage is around 15%. 

Sports betting is different. 

Oddsmakers make relatively good numbers to carve out a profit margin in betting markets. But sporting events introduce variables that are not as quantifiable as dice rolls or coin tosses. Emotion, road travel, injuries, and situations on the field and the court can impact the outcome. Making your own numbers and comparing them to the opening odds can help identify value in betting with your bets. 

Follow the Money, Honey 

Line shopping is essential to finding positive EV betting. Odds and betting lines are constantly shifting, so it helps to have multiple sportsbooks. And not all books have the same kind of customer base. Some books take much more action, some cater to casual bettors, while others have a higher percentage of big bettors. When a big player makes a move, a book pays attention and often moves a number out of respect for the sharp action. By contrast, if casual bettors are all over a public team on a marquee TV game, they'll be less inclined to move the number, knowing that the public is usually wrong. 

Staying Positive 

Positive EV (+EV) betting is a wager with a price lower than the "true odds" calculation. Consistently winning at sports betting is about putting the closing odds in your favor. There are several methods to utilize, such as a sports betting projections-based model, a market-based model, arbing, and value betting. None guarantees a win on every game, but they incrementally increase the percentages in your favor. Bookies make their profit on casual bettors who lose regularly—that doesn’t have to be you. Use these tips to start betting better, or grab my free Pro Picks to help you win more. 

+EV Betting Explained

A positive expected value is when the probability of cashing is higher than the odds implied by the price of that wager. Think of it as tilting the percentages slightly in your favor. If you think the Packers should be a 10-point favorite and they're only 3, that's outstanding value. You'd rush to the window to make a big play on Green Bay at -3. However, that line differential of seven extra points doesn't happen very often, as the oddsmakers aren't dummies. But if you find seven games that are off by just one point in your estimation, which is common for good handicappers, that's seven extra points on your side and could increase your chance of winning.

Moneyline Positive Expected Value Betting

The above calculation works the same with moneyline odds. Since the odds of a coin flip are 50/50 on heads or tails, the true odds are +100 (even). Moneyline odds are listed as -110 on the favorite and +110 on the underdog, or -140 and +130, etc. Expected value is a way to measure the probability differential between the sportsbook's expectations and those of sports bettors. 

Let's say the Giants are even-money on the moneyline (+100) against the rival Cowboys. A sports bettor has concluded that New York has several edges in its favor, should win the game, and should be a slight favorite. The posted odds are out of whack with the handicapper's expectations, creating Positive Expected Value. I’m always honing my systems to help me identify the matchups with positive expected value.

Minus-EV

The worst Super Bowl bet is the coin toss. While the true odds are +100 on heads or tails (50/50), the actual odds are -110 or even -115. The sportsbooks love it when people gamble on the opening coin toss because it’s the equivalent of throwing away money while hoping to get a win before the game even starts. The books are charging 52.38% at -110 for that +100 coin toss bet —a perfect example of negative expected value. which can increase your probability of losing.

Expected Value Importance for Bettors

Not every sporting event is a coin toss. There are plenty of underdogs where matchups by serious handicappers find they're capable of winning the game or should even be favored. It's that kind of positive expected value that I’m on the lookout for. Serious sports bettors are also known as EV bettors for this reason. Most bettors bet for the thrill but with strategies unfit for winning and growing a bankroll. Wagering by feel is great if you just want to throw a few bucks into the pot to add some excitement to a game, but if you really want to win, line shopping, finding edges, and channeling your emotion into the excitement of finding a positive EV bet is a more surefire strategy

Overvalued and Undervalued

Sportsbooks calculate the implied probability of the final score. The odds they post, however, are often tweaked. Money can move a line, as can public hype and media coverage. Adjusting the line from the true odds, even slightly, makes numbers overvalued or undervalued. A football team coming off a 40-3 blowout win gets the attention of fans and the media. Fans overreact to that one performance and can be in a hurry to bet on them the following week, no matter the number. Instead of opening as a 4-point favorite, they might open at -6 and get bet up to -7. Overreaction means overvaluation. The underdog in that example has a positive expected value of +7 when the line should be closer to +4 or +5. Scenarios like then are when I’m looking for matchup reasons to back the +7, recognizing there's +EV.

Why Overvaluation or Undervaluation Occurs

Sportsbooks aren't in business to predict winners. Their goal is balance, to lessen liability. Books adjust odds based on betting volume to ensure some profit, no matter the final score. They have no problem overvaluing or undervaluing an opening line because they're anticipating what the large pool of bettors, primarily casual players, are thinking. That pool of unsophisticated bettors is where they ultimately collect their small profit margin. That's the advantage of getting picks from someone like me putting in the time to study matchups and shifting odds to identify positive expected value and find you the best bets.

Super Bowl Defense 

A good example of overestimation is Super Bowl offenses versus defenses. The average bettor flocks to high-scoring teams. On Super Bowl Sunday, they figure the better offensive team with the better quarterback will win. However, pro bettors put a higher premium on defensive capabilities first. When Peyton Manning led the record-setting Denver Broncos offense in Super Bowl XLVIII, they were favored due to the public perception of their unstoppable offense. The public was on Denver, while sharp bettors recognized the No. 1 defense of the Seattle Seahawks was undervalued. It wasn't even close as the Seattle defense was the "unstoppable force" in a 43-8 rout. A similar thing happened when the No. 1-ranked Oakland Raiders offense faced the No. 1 defense of Tampa Bay in the Super Bowl. The Raiders were a 4-point favorite, but the superior defense dominated in a 48-21 Buccaneers blowout. Savvy bettors saw positive EV in the underdog with the dominant 'D'. 

Timing the Betting Market

Pro Tip: Waiting a few minutes before the game starts is more likely to get you a negative expected value than a positive one and possibly limit your probability of winning.

So, when is the best time for line shopping? It depends on the sport. With baseball, basketball, hockey, and soccer action taking place 24 to 48 hours after the previous game, that's the window for opening lines and variable movement. Many serious handicappers have their projections ready the instant odds are posted and can lock in expected positive value as they have a good idea which way the odds will shift. Football odds are posted six days before kickoff and sometimes longer. The best college and pro football bettors identify value early in the week. By Thursday, oddsmakers have made adjustments, and opportunities to find value bets diminish. 

Think Critically About +EV

Understanding positive and negative expected value increases your odds of collecting more profit from sports betting. It's a similar principle to what the best stock market players utilize: buy low, sell high. Begin with handicapping basics, such as analyzing matchups, stats, and situations. Then, make your own numbers based on critical thinking, more than "feel" or with your heart. The difference between winning, losing, and breaking even is slight. Before placing a wager, calculate when the best time is likely to make that bet to maximize positive expected value. There will be overvalued and undervalued lines, so getting the timing right is essential for winning handicappers. Most bettors lose, while the most successful bettors take advantage of everything to try and outsmart the sportsbooks. Or, you can always get my advice and start winning more without the effort.