Why Do Bookmakers Change Odds

Understand why bookies always change their odds, sometimes dramatically, and the main causes behind such sudden changes and fluctuations.

why do bookmakers change odds
Why Do Bookmakers Change Odds

No matter if you are a newbie in sports betting or have already wagered a decent amount of money for quite some time now, you probably have noticed one thing already - the betting odds always change. Sometimes, it's just by a few numbers but sometimes, the changes can be so drastic it can turn the tables between the favorites and the underdogs around.

When we're dealing with bookmakers, we're always interested in understanding why the odds change. What causes one bookmaker to offer a price on the Lakers winning the Knicks at +150 while another is quite happy to give that same bet away at +215? And a few hours later, each bookmaker's odds might swap for different ones. What makes bookies change their odds every few minutes?

But why do bookies do this? What is the basis on how much they would tilt the odds to one side? Here are the things you should know.

Reasons Why Bookmakers Change Odds

list of bets icon

There is only one thing that drives the bookies to change their odds: profit. In any game, there will be a 50% chance that each outcome will occur. However, bookies do not need a balanced amount of bets on both sides of the action.

We all know the basics of how they pay bettors: they pay out all those who wagered on the winning odds and keep the money of those who bet and lose. However, running a bookie operation is still a business that has operational costs and needs to turn in a profit.

This is where changing the odds comes in. By tipping the action on one side - depending on a number of factors - bookies ensure that they still make a profit regardless of which side eventually wins.

Factors That Affect Bookmakers Odds

Wondering what are the factors and biases bookies consider in changing the odds? Here are some of them.

Player Injury Reports

One of the biggest factors in bookies deciding to move the lines is player injury. When a key player on either team gets reported as injured or sustained an injury in their most recent game, that is more than enough reason for bookies to tip the odds to lean on the other side more.

Take for example a game where the Buccaneers would play. Now, Tom Brady has been reported to be injured and unable to play the game. If the Tampa bay team originally stood with an odds of -10, the report of Brady as injured would most likely send the odds slipping down to a -2 or -3 as the public would now less likely favor the team and may switch to the opposing one.

Market Demand

Sometimes, the bookies change the odds based on the sports betting market demand and how punters behave. This is to encourage other bettors to place their wagers on one side rather than the other.

Take for example an upcoming game between the Giants and the Raiders. Say that the bookies have gathered a total amount of bets for the Raiders at $220,000 with odds of +5.5 for a $200,000 payout. On the other side, the bets for Giants are at $165,000 with an odds of -5.5 and a potential payout of $150,000.

If Raiders win outright or lose only by no more than 5 goals, then they have to pay out a total of $200,000 while only keeping $165,000. That's a loss of $35,000.

What Do Odds Represent
Meaning of Betting Odds

Major News

Even developments in the team or individual player can tip the odds from the bookies, as this information can change the preference of the betting public. This is also why as a bettor, you also have to be in the loop when it comes to news about the game or teams you are betting on.

News that may affect the behavior of the betting market may include team lineup changes, coaches getting changed, suspended, or facing an issue, players facing public backlash due to recent behavior, or even a simple social media drama between teams.

Sharp Punters' Bets

Sharp partners are those who are experienced and skilled enough to predict the outcome of the game and see beyond what the bookies want you to believe. Most of the time, especially if they know that their pick is a really good one, they would go all-in and place a huge bet on one side of the action.

Say, for example, a bet of $100,000 on the Patriots. This immediately tips the action towards the team and changes the balance of the bet amounts - which is something the bookies do not like.

In situations like this, the sportsbooks have two options: to outright deny the huge bet of the sharp, or accept it and tip the odds more in favor of the other team now. This is to encourage the public and the squares into thinking that there is better value on the other side of the action.

How To Take Advantage of Bookmakers Changing Their Odds

Always keep in mind that the odds and lines are not an industry standard and each sportsbook decides the numbers they will publish. What does this mean for you, as a bettor? This is where line shopping comes in.

Line shopping refers to the act of checking out multiple bookies and trying to find which one offers better value for your money. One of the most common newbie mistakes is not doing line shopping - beginners usually assume that the odds they see are always the same for each bookie and thus, take no time comparing and contrasting anymore.

Thus, always make sure you check out other sportsbooks for the best odds. It's easy, anyway - all it takes is a simple visit on the bookie's site or app.

Now that you have a better understanding of how and why odds change, use this knowledge to place more strategic bets and hopefully, make more profit along the way, too.

This article was published on January 11, 2022, and last updated on June 24, 2022.