Definition of Over/Under Bet

An over/under bet, also O/U and over-under, allows the bettor to wager on whether an outcome for a statistic in a sporting event will be greater than (over) or less than (under) the amount that the sportsbook has predicted.



Some books refer to O/Us as total bets, and in the UK, it’s common to call them spread bets.



In the US, the most common form of the over/under bet is total points scored in a game, particularly an NFL game.



For example, if the Denver Broncos are at the Oakland Raiders this Sunday, a sportsbook may post an O/U of 42.5.



If the bettor takes the over, the Broncos and Raiders must combine for more than 42.5 points in order for him to win. If the bettor takes the under, the teams must combine for less than 42.5 points in order for her to win the bet.



Often, a sportsbook will post each O/U with a decimal or fraction in order to avoid ties.



In the event that ties are possible, the book will post how they handle ties, also called pushes.



Some sportsbooks handle pushes as no action, which means that they refund the wager but generally not the vig.



At some sportsbooks, ties win, in which case, the bettor wins.



At most sportsbooks, ties lose, in which case, the bettor loses.