Line movement in sports betting refers to the changes that occur in the betting line or odds for a particular event.

These changes can occur for a variety of reasons, such as changes in the expected performance of the teams or players involved, the announcement of injuries or other news that may affect the outcome of the event, or simply due to the patterns of betting activity on the event.

Line movement is a critically important factor to consider when sports betting, as it can provide valuable insights into the market and help you make more informed and profitable decisions.

Below, we’ll cover:

Step 1: Understand the Juice
Step 2: Convert Betting Odds into Implied Probabilities
Step 3: Evaluate Bets Using an Expected Value Framework
Step 4: Place Your Bets

Let’s jump in.

Sports bettors should pay attention to line movement

There are some fairly obvious reasons why sports bettors should pay attention to line movement including identifying value bets and better understanding market trends.

Identify value bets

Betting line movement can be a helpful indicator of value in sports betting, as it can provide insight into how the market is reacting to different factors and how the odds of a particular bet are being perceived by the sportsbook and the betting public. Here are a few examples of what you should be paying attention to:

1. Discrepancies between sportsbooks: By tracking the lines at multiple sportsbooks, you can identify discrepancies that may indicate value. For example, if one sportsbook has significantly different odds than others for a particular event, it could be an indication the odds at that sportsbook are not accurately reflecting the true probability of the outcome.

2. Line movement over time: Tracking how the line for a particular bet has moved over time can also be a helpful indicator of value. If the line moves significantly in one direction or the other, it could be an indication that the market is reacting to new information or that one side of the bet is being heavily wagered on.

3. Opportunities to “buy low” or “sell high”: When the line moves in a particular direction, it can create opportunities for bettors to “buy low” or “sell high” based on their expectations of the outcome. For example, if the line moves in favor of one team, bettors who believe that team is likely to win may be able to get better odds by betting earlier, while bettors who believe the other team is more likely to win may be able to get better odds by waiting until closer to the event to place their bets.

To illustrate this concept of “buying low” and “selling high,” let’s say the moneyline for the Chicago Bulls and the New York Knicks game is set at Knicks -5.5. If the line moves to Knicks -7.5, it could be an indication that the market is reacting to new information or that there is heavy betting on the Knicks. A bettor who believes the Bulls are more likely to win may see this as an opportunity to “buy low” and place a bet on the Bulls at better odds, while a bettor who believes the Knicks are more likely to win may see this as an opportunity to “sell high” and wait until closer to the event to place a bet on the Knicks at potentially better odds.

By paying attention to line movement and identifying opportunities to “buy low” or “sell high,” bettors can increase their chances of finding value and making profitable bets.

Analyze betting trends

Line movement can be a useful tool for identifying sports betting trends, as it can provide insight into how the market is reacting to different factors and how the odds of a particular bet are being perceived by the sportsbook and the betting public.

Generally speaking, by tracking the lines for a variety of events and markets, you can get a better sense of overall market trends and how the sportsbook is adjusting its odds in response to different factors.

To illustrate this concept, let’s say you are tracking the lines for a series of basketball games between the Brooklyn Nets and the Milwaukee Bucks. Over the course of the series, you notice the same line (the moneyline) for the Nets consistently moves in favor of the Bucks one hour before tipoff, even when the Nets are playing at home. This could be an indication that the market is reacting to the Bucks’ strong recent performance against the Nets, that the sportsbook are programmatically adjusting lines in favor of the away team close to tipoff, or that there is heavy sharp betting on the Bucks. A bettor who believes the Nets are undervalued based on this trend may see this as an opportunity to bet on the Nets and potentially find value, particularly before the predictable pre-tipoff adjustment.

By tracking line movement and paying attention to trends, bettors can improve their chances of making informed and profitable bets.

Betting lines move in a variety of ways

There are several different ways betting lines can move. Some of the most common ways include odds movements, spreads widening or contracting, and totals increasing or decreasing.

Odds movements

The odds for a particular event can change based on the amount of betting activity and the expectations for the outcome of the event. If there is a lot of betting activity on one team or side, the odds for that team or side may become shorter (more favorable, -110 to +110), while the odds for the other team or side may become longer (less favorable, +110 to -110).

Point Spreads widening or contracting

The point spread is the difference between the two teams or sides in a given event, and it is used to even out the betting odds. If the point spread widens, it means the perceived gap between the two teams or sides has increased (+3.5 to +7.5). If the point spread contracts, it means the gap between the two teams or sides has decreased (+3.5 to +0.5).

Totals increasing or decreasing

The over/under is a bet on the total number of runs, goals, or points scored in a particular event. If the over/under increases, it means the expected total number of points, runs, or goals has increased (Over 54 to Over 58), which may be a sign the event is expected to be high-scoring. If the over/under decreases (Over 54 to Over 50), it means the expected total number of points, runs, or goals has decreased, which may be a sign the event is expected to be low-scoring.

Betting lines move for a variety of reasons

Sports betting lines move for a variety of reasons including changes in the expected performance of teams or players and in response to market forces.

Changes in the expected performance of the teams or players involved

Sportsbooks adjust the odds of betting markets based on the expected performance of the participating teams or players; including whether or not certain players are expected to play.

Opening Day betting at @BetMGM

▪️ Odds
▪️ Line movement
▪️ Betting percentages pic.twitter.com/FVdVFLvslo

— John Ewing 🦁 (@johnewing) March 30, 2023

For example, let’s say that the Yankees are initially favored in their matchup against the Red Sox. The sportsbook may initially set the opening line for the Yankees to win at -200. However, if, just before the opening pitch, it is announced that Aaron Judge will not be in the batting order for the Yankees, the sportsbook may adjust the odds to +150 for the Yankees to win.

On the other hand, if the Red Sox were expected to perform poorly and the sportsbook initially set the odds for them to win at +300, but then it was announced that Rafael Devers would be returning from injury, the sportsbook may adjust the odds to +200 for the Red Sox to win (still the underdog, but with a better chance to win).

Changes in market forces

Market forces can also influence sportsbook odds. When a large number of bettors place wagers on one team or player, the sportsbook may adjust the odds in order to balance the amount of money wagered on each side of the bet and to maximize their profit.

Let’s go back to our Yankees vs. Red Sox example and assume the sportsbook initially set the odds for the Yankees to win at -200. If a large number of bettors place wagers on the Yankees to win, the sportsbook might be forced to adjust the odds in order to balance the money wagered on each side of the bet.

Alternatively, if a large number of bettors place wagers on the Red Sox to win, the sportsbook may adjust the odds for the Red Sox to win to +200 in order to balance the money wagered on each side of the bet and to maximize their profit. These types of scenarios can often lead to middle betting opportunities.

At any rate, market forces can influence sportsbook odds as the sportsbook adjusts the odds in response to the amount of money wagered on each side of the bet.

Booking “faces”

A common practice in the sports betting industry is known as “booking faces.” Sportsbooks “book faces” when they adjust lines based on who wagers money, rather than the amount wagered. Sportsbooks might “book faces” when they notice a group of particularly smart/sharp bettors have all taken one side of the line.

One specific example of a time when sportsbooks publicly “booked faces” was during the 2002 NFL playoffs. A sharp bettor known as Billy Walters placed a series of bets on the Oakland Raiders to win their playoff games against the New York Jets and the Tennessee Titans. As a result of these bets, the sportsbooks shortened the odds for the Raiders to win, decreasing potential payouts and attempting to attract bettors to place their money on the Jets and the Titans (to “fade” Walters).

Despite the adjusted odds, the Raiders ended up winning both of their playoff games and Walters (along with everyone who tailed his bets) was able to cash in.

How to predict line movement

Bettors who are able to predict where the line is going to move are better positioned to secure favorable betting odds.

There are a few strategies sports bettors can employ to better predict the movement of a betting line.

Monitor news and injuries

Injuries and other news can significantly impact the performance of a team and, in turn, the betting line. By staying up-to-date on the latest news and injuries, bettors can gain an advantage in predicting line movement.

Follow team-specific beat writers

Team beat writers often have access to more information and resources than the average sports bettor, and sometimes, the sportsbooks. By staying up-to-date with beat writers’ breaking news, sports bettors can access and digest news that might impact a particular bet before the sportsbooks or before the rest of the market, and can make predictions about how a betting line will move in response to more public dissemination of the news.

Consider public betting trends

The movement of a betting line is often influenced by the volume and value of bets placed by the general public. By keeping an eye on the public betting trends, sports bettors can get a sense of how the lines may move.

Bettor should pay close attention to reverse line movement

Reverse line movement (RLM) refers to a situation where the betting line or odds for a particular event move in the opposite direction of the expected or typical movement. Reverse line movement can be a sign there is something unusual or unexpected happening with the team, players, or market.

One potential reason for reverse line movement is when “sharp” money, or bets placed by professional or experienced bettors, is overwhelmingly on the other side of the line.

Identifying reverse line movement

Bettors can identify reverse line movement by monitoring the odds or lines and comparing them to their expected or anticipated movement. If the line or odds move in the opposite direction of the expected movement, it can be an indication of reverse line movement.

For example, let’s say a bettor is considering placing a bet on the Los Angeles Lakers moneyline versus the Golden State Warriors. Prior to the game, the sportsbook has set the opening odds for the Lakers to win at -200, indicating they are the favorite to win the game. However, as the game approaches, the bettor notices the original line for the Lakers to win has moved to +100, indicating they are now the underdog. The bettor searches for any breaking news about starting lineups, player news, or team news, that would account for the movement, but cannot find anything.

This sudden and unexplained shift in the odds could be an indication of reverse line movement, as the line has moved in the opposite direction of the expected line movement for seemingly no reason at all.

In this situation, the casual bettor could use this reverse line movement to their advantage by placing a bet on the Lakers, who, despite still being favored to win, are now being offered at an underdog price due to the reverse line movement.

By monitoring the odds or lines for a sporting event and looking for indications of reverse line movement, bettors can identify opportunities to pick off betting lines at inexplicably favorable prices.

Limited reliability of reverse line movement

Reverse line movement is not always a reliable indicator of value, as it can be influenced by a variety of factors that may not always be apparent. For example, reverse line movement may be caused by smart money, but it can also be influenced by other factors, such as changes in the expected performance of the teams or players involved or the announcement of injuries or other news that may affect the outcome of the event.

The vast majority of bettors simply do not have all the information available to the sportsbooks, so an adjustment to the odds which might otherwise appear as reverse line movement might, in fact, be caused by legitimate and outcome-impacting team or player updates.

Bettors should understand more advanced types of betting line moves

As sports bettors get more comfortable identifying and acting on line movements, they should take time to understand some more advanced types of betting line moves including steam moves, late moves, “head fakes,” and line freezes.

Steam moves

A “steam move”  refers to a situation where there is a sudden and significant shift in the betting line or odds for a particular event. Steam moves can be caused by one or more of a variety of factors such as changes in the expected performance, the announcement of injuries, or a sudden increase in the number of bets placed.

Sometimes, steam moves are caused by an unexpected influx of sharp money. For example, if a team is expected to perform well and the betting line is in their favor, but a large amount of sharp money is suddenly placed on the other team, it could cause a steam move in favor of the other team.

Bettors should avoid “chasing the steam.” For example, let’s say a group of sharp bettors place a series of large bets on the Dallas Cowboys to cover the spread against the Philadelphia Eagles. As a result, the sportsbook adjusts the odds for the Cowboys to win, causing a sudden shift in the line known as a “steam movement.” If a sports bettor sees this “steam movement” and decides to place a bet on the Cowboys to win based solely on the adjusted odds, they may be “chasing the steam.”

Figure out what you are good at:

1) Trends
2) Matchups
3) $$ Splits
4) Line movement
5) Value (+EV betting)
6) Bankroll Management

There’s plenty more…but always have a plan, stick to what works, and always keep discipline top of mind.

— HighRoller Sports Picks🎲 (@DM4LOCKS) March 29, 2023

“Chasing the steam” can be a risky betting strategy, as it involves placing a bet based solely on the sudden shift in the odds or line without considering other factors that could impact the outcome of the game, such as the teams’ performance, injuries, and player matchups. Bettors that “chase the steam” often feel like the wager is safe because it is aligned with the experienced bettors. But, as is often the case, the sportsbook has already adjusted the odds to account for the sharp action.

It is important for sports bettors to carefully consider all relevant player and matchup information before placing a bet, rather than simply chasing the “steam” based on the sudden shift in the odds or line.

Late moves

Line movements occurring close to the start of a game are often considered the most important line movements because they are typically influenced by the most up-to-date and relevant information about the event, such as the availability of key players or the weather conditions on game day.

Moreover, late line movements are often interpreted as sharp line movements because sportsbooks increase their betting limits just before games start, giving sharp bettors with large bankrolls full liberty to pour in on one side of the line, ultimately moving the line.

“Head Fakes”

A “head fake” refers to a situation where the betting line or odds for a particular game appear to move in one direction, but then quickly move back in the opposite direction.

Head fakes can be used by sharp sports bettors as a strategy to manipulate betting markets and potentially take advantage of less experienced or casual bettors.

For example, a sharp bettor may initially bet on a particular team or side, when the betting limits are lower (e.g. a $5,000 bet on the Cowboys’ moneyline) in order to cause the betting line to move in their favor, creating the appearance of value for that team or side. The sharp bettor may then quickly place a larger bet on the other side of the bet when the betting limits are increased closer to kickoff (e.g. a $50,000 bet on the Eagles’ moneyline), taking advantage of the perceived value created by the initial head fake and profiting from the resulting shift in the betting line.

By understanding and looking out for head fakes, sports bettors can avoid being misled by early line movements and make more informed betting decisions.

Line Freezes

A line movement freeze refers to a situation where the betting line or odds for a particular event are programmatically prevented from moving.

Line freezes can be implemented for a variety of reasons, such as to prevent sharp bettors from taking advantage of inside information or to prevent a sudden shift in the betting line due to a steam move.

One example of a sportsbook freezing a betting line occurred during Super Bowl XLIX in 2015. The New England Patriots were playing against the Seattle Seahawks. As the kickoff approached, there was a significant amount of betting action on the Patriots, and the sportsbook decided to freeze the line at Patriots -1.5 in order to limit their potential losses. This meant that even if the Patriots’ odds of winning improved, the betting line would not move in their favor, and bettors would not be able to place bets on the Patriots at better odds.

This is a common practice for sportsbooks in order to manage their risk and protect themselves from potential losses.

Conclusion

Line movement is a critically important factor to consider when betting on sports, as it can provide valuable insights into the market and help you make more informed and profitable decisions.

Now, the next time you consider placing a sports bet you’ll be equipment with the knowledge of how line movement works, what causes line movement, how to predict line movement, why you should pay attention reverse line movement, and some more advanced line movements like steam moves, late moves, head fakes, and line freezes.