Spread Betting - Spreads in Sports Wagering

Spreads in Sports Wagering

Spread betting was invented by Charles K. McNeil, a mathematics teacher from Connecticut who became a bookmaker in Chicago in the 1940s. The idea became popular in the United Kingdom in the 1980s. In North America, the gambler usually wagers that the difference between the scores of two teams will be less than or greater than the value specified by the bookmaker. An example:

• The bookmaker advertises a spread of 4 points in a certain game;

• If the gambler bets on the "underdog", he is said to take the points and will win if the underdog's score plus the spread is greater than the favorite's score.

• The eventual score is Underdog 8, Favorite 10: 8 + 4 > 10, so the gambler wins;
• The eventual score is Underdog 8, Favorite 13: 8 + 4 < 13, so the gambler loses.

• If the gambler bets on the "favorite", he gives the points and will win if the favorite's score minus the spread is greater than the underdog's score:

• The eventual score is Underdog 5, Favorite 10: 10 - 4 > 5, so the gambler wins;
• The eventual score is Underdog 8, Favorite 10: 10 - 4 < 8, so the gambler loses.

Spreads are frequently, though not always, specified in half-point fractions to eliminate the possibility of a tie, known as a push. In the event of a push, the game is considered no action, and no money is won or lost. However, this is not a desirable outcome for the sports book, as they are forced to refund every bet, and although both the book and its bettors will be even, if the cost of overhead is taken into account, the book has actually lost money by taking bets on the event. Sports books are generally permitted to state "ties win" or "ties lose" to avoid the necessity of refunding every bet.

A teaser is a bet that alters the spread in the gambler's favor by a predetermined margin – in American football the teaser margin is often six points. For example, if the line is 3.5 points and the bettor wants to place a teaser bet on the underdog, he takes 9.5 points instead; a teaser bet on the favorite would mean that the gambler takes 2.5 points instead of having to give the 3.5. In return for the additional points, the payout if the gambler wins is less than even money, or the gambler must wager on more than one event and both events must win. In this way it is very similar to a parlay. At some establishments, the "reverse teaser" also exists, which alters the spread against the gambler, who gets paid at more than evens if the bet wins.