How Does Baseball Betting Work?

How Does Baseball Betting Work

There are several ways to bet in baseball. These include: money line, run line, over/under, prop bets, and parlay.

Money Line

A money line bet in baseball places a wager on the on paper outcome of the game. In order to balance the skill level of the pitcher on the mound and team, teams are given different odds, or the probability the oddsmakers think each team has to win, for the public to place bets on for a given night.

For example, say a game between the Mets and the Marlins at Citi Field has the Mets at -170 odds and the Marlins at +140 odds. These numbers mean that the Mets are favorites and the Marlins are underdogs. The odds are based on bets of $100. If the Mets win and a bettor puts $170 on the team, they will come away with $100 of winnings. On the other hand, if the Marlins win and a person places a $100 bet on the team from Miami, they will win $140. Obviously, a $100 bet does not always have to be placed and the winnings are adjusted to the bet placed.

Run Line

Because games between uneven teams might have odds at extremes, most sportsbooks also offer a run line for bettors to consider. This line, or spread as it is called in other sports, evens out or flips the odds. The line is typically 1.5 runs, but can be anything, especially with live betting.

To explain how a spread works, let us say that the Mets get -1.5 runs and the Marlins get +1.5 runs from the example above. If the Mets win 5-4, the score based on the run line actually favors the Marlins 4-3.5. If the Mets win 6-4, though, the line still favors the Mets at 4.5-4.

The odds of the game can change due to the run line. Using the continuing example, the Mets may become +150 underdogs with a -1.5 line, while the Marlins become +130 favorites with the same line. This spread changes the odds because baseball is often a close game decided by very few runs.


The third form of common bets in baseball is the over/under. This type of bet has bettors predict the combined score from the two teams in the game. The line set by the oddsmaker generally takes into account prior matchups between the teams, the starting pitchers, and the lineup each team sends out onto the field. The over/under can be either a whole number or some number with .5 attached. The odds on the over and under depend on the number of people betting on each.

Going back to our previous example, say the over/under is set at 8 runs. If the score ends up being 6-1 regardless of which team wins, the under hits. Conversely, if the score is 8-1, the over hits. The tricky part happens when the score ends at 5-3. This score would constitute a "push." Because neither the over or under hit, the bet does not pay out anything and the bet is refunded. This push is the reason that many books add the additional .5 to the over/under.

Prop Bets

Prop bets are some of the most fun yet risky wagers a bettor can place on the MLB. These prop bets can be player based or based on other factors of the game. Some people might even take an over/under on the length of the National Anthem. Prop bets like these are especially popular during big games like the World Series and Opening Day.

Day-to-day prop bets are much more tame and game-focused. Back to our NYM-MIA example, assume Jacob deGrom is on the mound for the Mets with a strikeout over/under of 7.5. The lines for these bets will generally be pretty even in the -150 to +150 range. If deGrom strikes out more than 7, the over hits, and if deGrom strikes out less than 8, the under hits. Another example of a prop bet in baseball would be betting on if a run is scored in the first inning, or how many runs are scored on the first home run. Many books will put limits on these prop bets as they are not meant to be as lucrative but are rather placed as side bets.


A parlay is the term used when two or more bets are placed together on the same ticket. These bets can be almost any combination of bets within a game. Bettors can parlay the Mets winning and the under, or they can also bet on the Mets money line while also betting on the Yankees run line in the Bronx and the Cubs money line in Chicago. These bets have much higher payouts than regular, or straight, bets, but the risk is also multiplied.

Here is an example of a parlay. So, let us assume a Mets money line at +170, Yankees run line at -130, and Cubs money line at +150 with a $100 wager. If any of these bets do not hit, then no money is paid out. If the Mets win during the day then the bet pays out the $170 and adds it to the original $100 bet, so the bet on the Yankees is for $270. This bet then rolls over including the original $100 if the Yankees bet hits, and so on.


Sports betting is legal in some form, whether physical or mobile, in seventeen states. These states are: Arkansas, Colorado, Delaware, Illinois, Indiana, Iowa, Nevada, New Hampshire, New Jersey, New York, Michigan, Mississippi, Montana, Oregon, Pennsylvania, Rhode Island, and West Virginia. More states are legalizing sports betting because of the benefits the government gains from the taxes, though.

What happens if the line changes after a bet is placed?

If a bet has already been placed, the line changing means nothing and the bet remains the same. Because of this lack of change, some bettors will wait until they believe the line favors their bet. This wait is risky, though, as the line can move in the opposite direction. This reason makes timing a huge factor in sports betting as it can drastically change the amount of money won or lost.

What happens to a baseball bet if the game is rained out?

While the nature of a bet rained out depends mostly on the sportsbook, most of them follow similar rules. If the game is rained out in the first four-and-a-half innings, all bets depending on the end of the game are cancelled as the game is not officially finished. For an over/under or run line bet to stand, the game must go at least eight-and-a-half innings. For money line bets, if the game is called with a winner, the team who receives the win cashes out.

Can you bet on end-of-season outcomes and awards?

Yes, and these bets are some of the most popular at the start of the season because of the great payouts they offer. Bettors can wager on anything from the World Series champion, division champions, the Most Valuable Player winner, or the Cy Young Award Winner. Some bettors will even place small bets on struggling teams for the potentially massive payout.