How Do Football Odds Work?

I like to start these posts by thinking of what question my reader might be asking themselves. In this post, I’m assuming you’re asking. how do football odds work?

Football odds are the tools used by oddsmakers to create betting markets.

Betting odds are displayed in standard formats and use numbers and symbols to identify betting opportunities for their customers. Learning to read betting odds is easy; making successful bets consistently is difficult.

This post outlines the common ways football odds are displayed, including money lines, point spreads, game totals, and other standard bets. Read on to learn how football odds work, how to read them, and how to use the information they contain to make smarter NFL wagers.

How Do Football Odds Work – Plus and Minus Odds

It would be impossible to bet on the NFL without understanding plus and minus odds and how football bets are formatted.

Underdogs are listed with plus numbers, indicated by a literal “+” symbol. Because these teams are expected to lose, books sweeten the deal by offering plus money. The number listed next to a plus symbol indicates a bettor’s payout for every $100 wagered. A successful $100 bet on a team with +100 odds would result in a $100 payout.

Favorites are listed with minus numbers, indicated by a literal “-” symbol. Because these teams are expected to win, books limit the payout to people who back them by offering minus money. The number listed next to a minus symbol indicates the amount a better needs to lay to win $100. A successful $100 bet on a team with -200 odds would result in a $50 payout.

How Do Football Odds Work – Forms of Football Odds

Understanding the five forms of odds listed below will prepare you to place every common NFL bet available:

The Money Line

The money line is the simplest way football odds are displayed. In money line bets, you win if you pick the overall winner. There’s no other consideration made; bet for the winner, you get a predetermined payout. Bet for the loser, you win nothing.

Here’s an example of a money line from the opening week of the 2021 NFL season:

Dallas +215
Tampa Bay -275

In this layout, the visiting team is always listed first, followed by the home team. We know that Dallas is visiting Tampa Bay as the underdog, thanks to their plus number, +215. We also know that Tampa Bay (the home team) is a strong favorite, thanks to their minus number, -275.

Backing Dallas on the money line means taking a bigger risk for a bigger payout; the opposite is true for a bet on Tampa Bay. A successful $100 bet on the Cowboys would result in a payout of $215, while you’d need to bet $275 on Tampa Bay for a $100 payout should the Bucs win.

The Point Spread

A point spread is a kind of leveling system used by books to create a unique betting market. Oddsmakers assign each team a buffer. The favorite is assigned a negative number which indicates the number of points it must win by to payout. The underdog is assigned a positive number which indicates the number of points an underdog can lose by and still payout.

Let’s go back to the example from before but use the point spread format:

Dallas +7.5
Tampa Bay -7.5

Dallas backers can win their bet so long as the Cowboys win outright or lose by less than 8 points. Bets on Tampa Bay only payout if the Buccaneers win by more than a touchdown.

Most point spreads give equal odds (-110) to both sides. That means you’ll win back $100 for every successful $110 point spread bet. That was the case with this Cowboys-Buccaneers game.

The Game Total

A game total is a number set by oddsmakers. It’s a guess as to the final point total for both teams. Books take bets on whether the actual total will be over or under the line they set. That’s why game totals bets are sometimes called over/unders.

The game total is usually displayed as part of another line. Let’s update our point spread example from above with the actual game total from that 2021 game:

Dallas +7.5 (O 52.5)
Tampa Bay -7.5  (U 52.5)

In this example, the game total is 52.5. The oddsmaker who released this number set that as the total for bettors to bet over or under. As with the point spread, most game totals bets get odds of -110.

How did it go in the Cowboys game? The final score was Tampa Bay 31, Dallas 29. That means the Cowboys “covered the spread,” and bets on Tampa Bay lost, while those who backed Dallas took home a nice win. The final game total was 60, meaning over-backers were the winners.

NFL Futures & Props

These so-called exotic wagers have a few things in common: they promise big payouts, they require a lot more luck, and they offer worse odds than standard bets. Generally, these are wagers on the outcome of future events or the performance of individual players.

Consider a common futures bet in the NFL – picking the future Super Bowl winner. Technically, you’ve got a 1 in 32 chance of picking the future champion before the season even begins, just by the luck of the draw and random chance. Most books list each team with a plus number – Buffalo Bills +700, for example. Back the Bills with a $100 bet and you’ll win back a sweet $700 payout.

Props are another type of exotic NFL bet. This is just a form of futures bet in which a specific proposition is made by the book and listed with odds. You might see something like “Will Tom Brady throw more than 2 TD passes? Yes +200, No -200.

How Do Football Odds Work – How to Read Football Odds

The first step in reading football odds is working out what type of odds you’re reading. The numbers and other features of a line may mean something different depending on the context.

For example, when you see O/U, that’s the symbol for a game total (or over/under) bet. When you see a number that’s the same for both teams except that one team has a plus and one has a minus, that’s a point spread. When you see two different numbers (and one has a plus and one has a minus), that’s an NFL money line.

Knowing what you know about reading football odds, you should be able to read this set of odds:

Pittsburgh +240, +7 (O47.5)
Buffalo -280, -7 (U47.5)

Here, the Steelers are visiting the Bills as 7-point underdogs. The game total is 47.5.

That’s the easiest way to interpret a set of football odds. You don’t need to start worrying about the money amounts until you figure out which side to back.

How to Calculate Implied Probability

You can calculate the implied odds of every bet on the board. This will help you determine areas where you find value. Here’s how it works:

To calculate minus odds into a book’s implied probability, divide the minus number by itself plus 100 times 100. If that sounds like gibberish, let’s use the Pittsburgh and Buffalo example from above.

Buffalo’s implied probability of winning is 280/(280+100)*100, or 73.68%.

To calculate plus odds into implied probability, divide 100 by the plus number plus 100 times 100. Here it is from the Pittsburgh/Buffalo example:

Pittsburgh’s implied win probability is 100/(240+100)*100, or 29.4%.

A simplistic but effective advantage gambling tactic you can practice with this information – if you think Buffalo has a better than 73.38% chance of winning, back the Bills. If you think Pittsburgh has a better than 29.4% chance of pulling off the upset, back the Steelers.

Why Do Football Odds Change?

Oddsmakers can’t control the outcome of games. The odds of a given outcome change throughout the betting week and even during a game. Markets change because of new information (injuries to players, trades, lineup changes), changes in the betting public or market confidence and changes to the way money is wagered.

Changes to lines can be used as a way for oddsmakers to correct for fluctuations in the betting market. While oddsmakers don’t always pursue a perfectly-balanced book, they do change odds to protect their ability to continue doing business.

Gamblers can use these changes in football odds to their benefit. Some bettors use bet-hedging tactics based on this line movement and disparities between lines from different oddsmakers to protect their bets or even guarantee a profit. Read our coverage on how to hedge bets here.

Conclusion

If you were wondering at the beginning of the post, how do football odds work, you should probably be pretty happy right now. But if something wasn’t clear, or if I left something out, leave me a comment so I can improve this post.

Remember that the best sports bettors in the world struggle to win more than 53% of the time. Football betting is hard; reading the odds and understanding the bets available shouldn’t be.

You can learn to read football odds in just a few minutes. Learning to win consistently is a different story.