Underdog Betting: High Risk, High Reward?

Betting on the underdog allows you access to bigger odds, but the wager comes with risks. Over the long term, betting the underdog will lose you more money than you’ll win. In this guide, we’ll show you how to bet the underdogs at the best sports betting sites and make bigger long-term profits. 

What is Betting on the Underdog?

Let’s start by showing you how to bet on the underdog. In each game, the bookmaker assigns odds based on the favorite and underdog. They assign an implied probability to each player or team, based on their likelihood of winning. The bookmaker also factors in its own vig to the odds. 

For example, imagine an underdog has a 40% chance of winning a game. The betting odds are presented as +140, meaning that you win $140 for a $100 bet, plus your stake. 

The favorite is a 52% chance, and the odds are given as -110. That means you win $100 for every $110 placed, plus your original stake. 

The bigger the odds, the lower the chance of the underdog winning. A team with odds of winning should win 1 time in every 6 chances. However, upsets do happen, and that’s when you can use an underdog betting system to beat the house. 

How Does Underdog Betting Work?

It’s easy to spot the underdog in a sports betting market. On paper, the underdog has a statistically lower chance of winning a game. That’s reflected in the bookmaker’s odds. The betting site offers more money if the underdog wins but keeping its return low if the favorite wins. 

You place an underdog bet in the same way as you would a favorite. Your stake is set at 1 unit. Typically, your return for 1 unit is more than 1. So, with odds of 6/1 you’d receive $6 for every $1 you wager. 

There are some immediate telltale signs of an underdog in a bookmaker’s match-up:

•    Long odds: The underdog will have positive odds to represent their second billing behind the favorite. At odds of 3/1, you win $3 for every $1 wagered. 
•    Relative Team Strength: The underdog will have a weaker team and players. They may be languishing low in the league or be recently promoted. 
•    Recent Form: A player or team is on a long run of poor form. The underdog may even be a traditionally strong player who’s coming back from injury

Underdog Betting by Bet Type

Let’s examine how betting on the underdog works across a range of common bet types. 

Moneyline

The moneyline bet is a straight wager on the winner of a two-handed game. The favorite is assigned negative odds, reflecting their status as favorites. The underdog has positive odds so reflect the lower implied probability.

•    Underdog Team A: +155 odds
•    Favorite Team B: -185 odds

Point Spread

The point spread is a handicap wager where the underdog is assigned a points advantage before the game starts. The favorite must overcome their relative points deficit to “win” the game, or “cover the spread”. 
You can compare the difference in odds between a moneyline price and a point spread. 

For example, let’s take a look at an NFL game between the Detroit Lions and LA Rams. The Lions have around a 65% chance of winning, with the Rams the underdogs on 39%.

Moneyline odds:

•    LA Rams: +155
•    Detroit Lions: -185

Now let’s compare the new odds once you’ve assigned a point spread of +3.5/-3.5 points:
•    LA Rams +3.5: -110
•    Detroit Lions -3.5: -110

The odds for both teams are now equal at -110. With a +3.5-point head-start, the Rams now have parity with the Lions. 

Totals (Over/Under)

The Over/Under bet is a wager on the total number of goals or points in a game. It’s irrelevant who wins the game, just the total points. 

In our example, the bookmaker goes -110 on both Over 50.5 points and Under 50.5 points. The beauty of the O/U bet is you don’t need to know who the underdog is. However, with a classic big favorite vs underdog match-up, the total points may be higher than normal.