Understanding Juice and Line Movement in Sports Betting

What Is “Juice” (Vigorish) in Sports Betting?

Juice (also called vigorish or vig) is the commission a sportsbook charges for taking a bet. This fee is built directly into the odds, ensuring the bookmaker earns a profit regardless of a game’s outcome. Essentially, it is the cost of placing your bet.

Juice in Standard Odds

The most common way to see juice is in standard point spread odds of -110. This figure means a bettor must risk $110 to win $100. That extra $10 you risk is the sportsbook’s commission.

• If two bettors place opposing $110 wagers at -110, the book takes in a total of $220.
• The winner receives their $110 stake back plus $100 in profit.
• The losing bettor loses their $110 stake.
• The sportsbook pays out $210 and keeps the remaining $10 as revenue.

The House Edge and Break-Even Point

At standard -110 odds, the sportsbook has an edge of approximately 4.76%. This percentage is the house’s built-in profit margin, or hold.

The juice also directly affects your required break-even rate:

• To break even on even-money bets (+100) with no juice, you’d need to win exactly 50% of the time.
• With the typical -110 odds, a bettor must win 52.38% of their wagers just to break even in the long run.

The Impact on Your Winnings

Juice cuts into your payout. If you bet $100 and win:

• At even odds (+100), you would profit $100.
• At standard juice (-110), you profit only $90.91.
• At reduced juice (-105), you profit $95.24.

This small difference compounds quickly. One analysis showed that a bettor who hits 50% of 72 NFL spread bets would lose about $180 with standard -110 juice, but only around $90 with -105 lines, saving almost half their losses just by reducing the commission.

The Value of Reduced Juice

The industry standard is the “10-cent” line (-110 on both sides). However, some sportsbooks offer reduced juice, such as a “5-cent” line where odds are set at -105 on both sides of a wager.

A bettor who wins 55% of their wagers will see a much higher overall profit at -105 odds than at -110. Consistently choosing reduced juice lines is one of the most effective ways to lower the house edge and increase your potential winnings.

What Is Line Movement in Betting Markets?

Line movement is the term for any change in a betting line—such as a point spread or moneyline odds—from the time it opens until the time the game starts. Betting lines are dynamic, shifting as sportsbooks react to new information and, most importantly, the flow of money.

A line move could mean a spread changing from Team A -6.5 to -7.5, or moneyline odds shifting from +150 to +130.

Key Drivers of Line Movement

Lines move for four main reasons:

1. Betting Patterns (Money Imbalance): If a massive amount of bets or money comes in on one side of a wager, the bookmaker will adjust the line. The goal is to make the popular side less attractive (e.g., Team A -6.5 moves to -7.5) and encourage bets on the other side (Team B) to balance their financial risk.
2. New Information: Significant news—like a sudden star player injury, a last-minute weather forecast change, or a roster move—can quickly render the opening line inaccurate. Oddsmakers adjust to reflect the new reality.
3. Sharp Money vs. Public Money: Sportsbooks give more weight to wagers placed by “sharps” (professional bettors with a proven winning history) than to casual public bets. A few large bets from respected sharps can move a line more dramatically than a large volume of small public bets.
4. Risk Management Strategy: Before moving the point spread, sportsbooks may first adjust the juice to test the market. If there is heavy action on one side at -110, the book might move that side to -120 to make it more expensive, while offering better odds on the other side. This is an early warning sign that the full line is about to move.

How Line Movement Works: From Open to Close

Opening Lines

Sportsbooks set opening lines based on their own statistical models and power ratings. For major markets like the NFL, sharp “market-making” books often post lines first and quickly adjust them based on early action. These early sharp bets serve as a way for the market to correct any “soft” or inaccurate opening numbers.

Line Adjustment and Copycat Moves

As the week progresses, oddsmakers constantly monitor the liability on each side. If 80% of the money is on one team, they will adjust the line to mitigate risk. For example, if the Yankees are heavily bet at -150, the book might move them to -170 to encourage some bets on the underdog.

Line moves often spread across the industry. If a sharp, influential book (like Pinnacle) dramatically moves a line, other sportsbooks will often copy the move instantly. They do this to avoid having a “stale” number that sharp bettors can exploit.

Reverse Line Movement (RLM)

One of the most valuable concepts for a bettor is Reverse Line Movement (RLM). This occurs when the betting line moves in the opposite direction of the betting percentage.

• Example: If 75% of the betting money is on Team X -4, but the line surprisingly drops to Team X -3.
• Interpretation: The RLM suggests that influential sharp money is backing the less popular side (Team Y, the underdog). The sportsbook is shifting the line against the public to limit its exposure to the smart money.

Closing Lines

The closing line is the final number available just before the game starts. It is considered the most efficient and accurate reflection of the true odds because it incorporates all known information, all line adjustments, and the collective opinion (and money) of the betting market.

• A key metric for successful bettors is Closing Line Value (CLV)—how often you place a bet at better odds than the closing line. Consistently beating the closing line is a strong indicator of long-term profitability.

Strategies Using Juice and Line Movement

Understanding the dynamics of juice and line movement is not just for information—it’s a powerful tool for strategic betting.

1. Line Shop for Value

This is the most critical and simplest strategy. Always check multiple sportsbooks to find the most favorable odds. If one book offers a line at -7 (-110) and another offers it at -6.5 (-110) or -7 (-105), you must choose the better number. Consistently getting a better price saves money on juice and increases your winnings over time.

2. Time Your Wagers Strategically

Decide whether to bet early or late based on anticipated movement:

• Bet Early: If you like an underdog and anticipate the public will bet the favorite, which would push the underdog’s line up (e.g., you bet +3 and expect it to reach +4), you might wait to bet later at the better number. Conversely, if you like a favorite and expect sharps to shorten the line, you bet early to grab the initial number before it moves.
• Bet Late: Waiting gives you the benefit of all known information (injuries, final weather). However, you risk missing the best line if the market has already moved it.

3. Follow Reverse Line Movement

When you spot RLM, where the line moves against the public’s betting majority, it is a strong signal that sharp bettors are taking a position on the other side. This is often a good time to consider betting on the less popular team, essentially “tailing the smart money.”

4. Read the Juice Changes

A change in juice can be an early warning sign of an impending line move. If you see a favorite at -6.5 (-120) at one book, it suggests the book is highly considering moving the line to the key number of -7. If you want the -6.5, you should act quickly before the line adjusts further.

The more you study juice and line movement, the more you can approach sports betting as an analyst looking for value, rather than a gambler simply making a pick.