When the point spread was invented in Chicago by Charles McNeil the money line took a backseat. When two unevenly matched teams played, the playing field was leveled by having the favorite give points (for example Chicago Bears –7) while the underdog got points (Minnesota Vikings +7). No matter which team the bettor took the bettor would always risk $110 to win $100. The extra $10 needed to win $100 is called the juice or the vig, it is basically the house’s or the bookie’s take. It’s 10-percent of the bet so it would take $33 to return $30 and $440 to return $400 etc. (winning bettors get the vig back).
You may be wondering how we determined which of the two teams was the favorite and which was the underdog. You may also be wondering how much you get paid out for a bet on either side of this game. If you look at the odds above (this is a screenshot from an actual online sportsbook), you’ll see that all of that information is given to you. Before the spread number of 4 ½, you’ll see a plus or minus sign. The plus sign indicates the underdog and the minus sign indicates the favorite.
We already mentioned how using multiple betting sites allows you to take advantage of multiple bonus offers. That's not the only benefit either. Since point spreads vary between sites, one of the best ways to beat these wagers is to compare the different spreads in order to find which one is the most favorable. This doesn't take nearly as long as you might think, and it will make a huge difference to your bottom line over time.
The point spread is basically used to create a 50/50 betting proposition. In this example, the Celtics are theoretically just as likely to win by six points or more as the Grizzlies are to lose by less than six points. This is reflected in the odds, which are typically -110 on both sides of the wager. You have to risk $110 for the chance of winning $100.
Sometimes with NFL odds you’ll see a spread posted as a whole number. Decimals or fractions are usually utilized to ensure there won’t be a tie. If in our example the spread was reset to 10 with the Colts favored and they win by 10, then the game is considered to be a tie, which in betting terms is called a push. If there is a push all bets are off and the sportsbooks return all wagers back to the bettors.
In the brackets after the last two games, you will see the odds associated with each of the bets. Let's say we made our earlier example bet of the Chargers -3 and the final score of the game was Chargers 21, Cowboys 14. Looking at this, we already know that we won our bet, but just how much money are we going to get paid? For this bet, we will get paid even money because that is what is posted in the parenthesis. This means that if we bet $100, we will profit $100 for winning our bet.
A common mistake that new bettors will do is to bet every single game. Unfortunately, this is not a winning strategy no matter how sharp you are. Stick to betting the games where you actually see value. Here's what we mean by value. Let's say in our earlier example that you agree with the sportsbook that the Florida Gators should win the game by seven. You should not bet this game then no matter what if the line is -7. If you're right, the best you can do is tie on your bet. When you pick a side, you're basically going to be guessing and flipping a coin. Theoretically, you'll win as many times as you lose, but you'll be paying the house percentage every single bet and slowly bleeding your money and profits away.
Armed with the knowledge of how to remove vig, it's now possible to prevent yourself from making the same mistakes that the majority of bettors make. Most bettors understand the importance of line shopping (i.e. comparing the lines and odds at different bookmakers and betting sites). However, if they fail to also understand how moneylines and vig work, then they're probably going to make wagers where they think there's positive expected value (+EV), even though there's not.
A point spread in sports is a figure set by oddsmakers to provide an advantage or disadvantage based on the margin of victory or defeat for a given team. The “favorite” team (labeled with a “-” sign) would be at the disadvantage as they would need to win the game by a set number of points while the “underdog” team (labeled with a “+” sign) would be given an advantage to not lose the game by a set number of points. The reason oddsmakers do this is to provide betting interest for both sides due to one team typically being better than the other.