Bookie

What Is a Bookie?

The term bookie is short or slang for "bookmaker." A bookie is someone who facilitates gambling, most commonly on sporting events. A bookie sets odds, accepts, and places bets, and pays out winnings on behalf of other people.

Key Takeaways

  • The term bookie is slang for "bookmaker."
  • A bookie is someone who facilitates gambling, most commonly on sporting events: They set odds, accept, and place bets, and pay out winnings on behalf of other people.
  • The bookie's goal is to maintain balance in the books by adjusting the odds as much as possible so that there's an even amount of people betting on a win or loss.
  • A 2018 U.S. Supreme Court ruling opened the door for sports betting throughout the country if states decide in favor of it.

Understanding Bookies

Bookies do not usually make their money by placing bets themselves, but by charging a transaction fee on their customers' bets known as a "vigorish," or "the vig." Bookies may also lend money to bettors. A bookie can be an individual or an organization.

Although the term bookie has been associated with illegal activity, with the expansion of sports betting, a bookmaker has become a legitimate occupation. However, bookmaking and placing bets through a bookmaker can still be illegal. The legality of different types of gambling is largely determined by state governments.

Sports Betting

Throughout most of the 20th and 21st centuries, in the U.S. sports betting had only been legal in Delaware, Montana, Nevada, and Oregon. As a result, a black market developed for the rest of the country whereby illegal operations of bookies provided opportunities for betting. While some bookies are involved in organized crime, others operate independently, simply taking bets for a few friends, family members, or colleagues.

However, in 2018, the U.S. Supreme Court struck down the Professional and Amateur Sports Protection Act, which was a federal law preventing states from deciding on their own whether to allow sports betting. The ruling opened the door for sports betting throughout the country if states decide in favor of it.

With the expansion of sports betting in various states, bookies are likely to see increases in betting activity, while states are expected to generate additional revenues.

Big casino operators are also looking to cash in on sports betting; MGM Resorts, for example has a partnership with MLB as the official gaming partner. Other companies and bookies are likely to expand into social media services such as Facebook, to access potential betting customers.

Bookies and Setting the Odds

One of the most critical ways bookies ensure their winnings is by calculating the odds that they will win an event, sometimes by employing teams of statisticians and developing complex models. The terms lines (“money lines”) and spreads (“point spreads”) are critical factors for bookies. Sometimes these calculations are based on those, developed by casino actuaries or those who deal with risk calculations.

Typically, they underscore which sports team the bookies believe will win a game or match. The lines and spreads can be adjusted in the time leading up to the event, based on various bets made in their books, along with fluctuations in Vegas casino bets. Other unexpected events might impact the odds such as poor weather, player injuries, and doping scandals.

The bookie's goal is to maintain balance in the books by adjusting the odds as much as possible so that there's an even amount of people betting on a win or loss. If the book is balanced, the bookie earns the transaction fees. However, if there's a one-sided bet on a particular team or outcome, the bookie has an increased risk of losing money.

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  1. CNBC. "Supreme Court’s legal sports betting decision: Three key unanswered questions." Accessed Nov. 1, 2021.