How do sports betting odds work?
For each game and event available for wagering, sportsbooks will attach odds to the available choices. The odds tell you which outcome is the favorite — i.e., the more likely one to happen — and can also point you to the potential return on winning bets.
On that last point, it takes some calculating to figure that out. We’ll walk through the steps in a bit. For now, let’s examine how the odds work for each of the main types of sports bets.
A moneyline wager is a straightforward one in which you simply have to choose the winner. The odds on the favored side will be negative, while the number will be positive on the side of the underdog.
- Tampa Bay Rays +110
- Los Angeles Dodgers -130
For this matchup, the Dodgers are slight favorites over the Rays. A small difference between the two numbers points to a potentially close game, while a wide span indicates a paper mismatch in the eyes of the oddsmaker.
Point spread odds
The point spread is most commonly available in football and basketball betting, but there are also variations for other sports. Oddsmakers install the spread, which is akin to an estimated margin of victory.
- San Francisco 49ers +2.5 (-110)
- Kansas City Chiefs -2.5 (-110)
For this game, the Chiefs are favored by 2.5 points, as indicated by the negative number on that side. To cover the spread, Kansas City needs to win the game by a margin greater than the number, such as by three points.
The 49ers cover by keeping the margin under 2.5 points or by winning the game outright. There are two components to spread betting lines: the amount of the spread, and the actual odds for each side of the wager (listed in parentheses for our example.)
Also known as totals betting, this wager type revolves around the total number of points that two teams will score in a contest. Sportsbooks set a benchmark number to consider, and bettors then can choose over or under that amount.
- Over 49.5 (-110)
- Under 49.5 (-110)
The projection is 49.5 points here, so over bettors are looking for 50 or more total points in the game. Under bettors will have winning tickets if the total points wind up at 49 points or fewer. There will be odds on both sides, such as the -110 in our example.
Other types of bets you can make:
- Prop betting: Prop bets are additional wagering opportunities for individual games and events. They’re basically like side bets on things that may happen during the proceedings. Many prop bets revolve around the statistical accomplishments of players.
- Live betting: This wager type affords users the opportunity to bet in real time as the action plays out. Also known as in-game bets, this is a fast-moving market that continues to surge in popularity. Odds and offerings will be based on what’s happening on the field of play.
- Parlays: Parlay betting is a popular bet that provides users the chance for enhanced returns. You can build a parlay with two or more outcomes. The potential return increases with each selection added, but the chances of winning decrease as well.
- Teaser and pleasers: For these two bet types, you as the bettor gain additional control over the point spread. In the case of a teaser, the spread on two favorites could be adjusted downward. When you place a pleaser bet, the opposite occurs. The spread moves in the other direction.
- Futures: Odds for futures are released in the offseason for the respective sports. Bets begin coming in soon thereafter, and the odds board will adjust based on the action that comes in and as the season starts and continues. The general idea is to find the choices you are interested in at the best possible prices.
How to read sportsbook lines and calculate payouts
Sports betting lines for team-based sports follow a standard format. The two teams set to face off will appear with the home team on bottom and the road team on top, but keep in mind that there’s an occasional neutral-site affair to deal with.
Right next to the two team names will be a series of numbers for the main bet types available. For an NFL game, the listing might look something like this.
- Tampa Bay Buccaneers +3.5 (-110) +155 O 52.5 (-110)
- Pittsburgh Steelers -3.5 (-110) -175 U 52.5 (-110)
If we read from left to right on the numbers, these are the lines for the big three bet types: point spread, moneyline and totals. The Steelers are 3.5-point favorites and favored on the moneyline, and the over/under is at 52.5 points.
At online sportsbooks, listings will follow a similar format, but there will be some slight differences depending on the sport. For example, MLB uses a run line instead of a spread, while a goal or puck line is standard for NHL betting.
As mentioned, sports betting odds also point us to the potential payouts for winning bets, but it takes some calculating to figure out. There are two quick ways to figure it out. First, there are formulas to use that will vary based on the direction of the odds.
- If the odds are negative, drop the minus sign: Bet amount / (Odds/100) = return
- If the odds are positive: Bet amount * (Odds/100) = profit
To calculate, you simply need to plug in the amount of your wager and the odds. Here’s how it works using a bet amount of $100 and an odds split of -110/+130.
- Negative: $100/(110/100) = 90.90
- Positive: $100*(130/100) = 130.00
Next, there’s a quick and easy way to get a ballpark number of what kind of return you’re looking at. When the odds are negative, the number also represents the amount you would have to wager to see a return of $100.
In the case of -110, you’d be wagering $110 for the chance to win back $100. If the odds are positive, the number is the amount you’d get back for a winning $100 bet. For a $100 wager at +130, the return would be $130.
What you can’t bet on in the US
You can bet on all of the major team-based sports — NFL, NBA, etc. — the top individual sports — golf, UFC, etc. — and a host of niche sports such as cricket, rugby, etc. Offerings in the last category may vary by operator, but the first two categories generally appear everywhere.
It’s a different story when it comes to non-sport events. Here are a few examples of what you won’t find available for wagering at legal and regulated sportsbooks.
- TV competitions
- Court cases
- Economic data
On a state-by-state basis, there are certain restrictions in place, many of which revolve around college sports and amateur competitions.
House rules when it comes to lines and how a bet is settled
Each online sportsbook has its own set of house rules in place. The rules cover things like bet placement and settlement, as well as how things are handled when various circumstances come into play.
Many of the rules are pretty standard across the industry, but there are some variations among operators. Here are some of the main points that you need to know.
- Bets are considered action once the game or event gets underway.
- Settlement for all wagers often is based on official league data and results.
- In the event of a complete cancellation, bets will be voided with wager amounts refunded to users.
- For events that are delayed because of weather or other issues, bets may remain live as long as the contest is completed in a reasonable period of time.
- Sportsbooks will treat spread and total bets in which the outcome lands exactly on the number as a push, refunding the wager amounts to users.
Those are the basics, but we again point out that random circumstances will come up here and there. The exact way they are handled can vary by operator. For specific details, it’s always a good idea to review the house rules or terms and conditions at the sportsbooks you are using.