How do bookies make money?

Ten dollars on every game

Say one player takes each side of a game for $110. The book is holding $220, it pays the winner $210 (his $110 back plus $100), and it keeps $10 without having had an opinion on the game at all. That is 4.55 percent of the money wagered. It is called the vig, or the juice, and it is there on every bet whichever side wins.

The bets that pay the book best

The cut is not the same on every kind of bet, and this is the table I'd want every new player to see.

Bet	The book's cut
Straight bet at -110	about 4.5 percent
Prop at -115 both ways	about 6.5 percent
Two-team parlay	about 8.9 percent
Five-team parlay	about 20.8 percent

So a book makes its thinnest margin on the bet a serious player makes, and its fattest on the ones a weekend player likes. That is why the front page of a sportsbook is parlays and props. Nobody puts the cheap stuff in the window.

It is not a sure thing

The 4.55 percent is theory, and it assumes the money is split evenly, which it almost never is. Recreational players tend to land on the same favorites and the same overs, so on a given Sunday the book is rooting for one set of results like everybody else in the building. What the book actually keeps is called the hold, and it swings. A book can lose for a week, or a month.

Over a season the price does its work, provided the book has the bankroll to get there. I'd put that proviso first, not last. A book with the right prices and not the money to ride out a bad month is still a book that goes under.

How a book protects the margin

Limits come first: it takes less from players who beat it and more from players who don't. When one side carries more risk than the book wants, it moves the line, either the number or the price. And a local bookie has a third job the big books mostly skip, which is credit control, because he only makes what he can collect, and a player who loses and doesn't pay is a loss, not a win. The bookmaking guide covers each of these.

Paying less of it

You can't bet without paying the cut. You can pay less of it. I'd make straight bets and shop for -105 where I could find it, and I'd keep parlays and props small, because the charge on them is higher, and on a long parlay it is several times higher. Set your stake against your bankroll, not against last week's losses.

The book doesn't need you to lose every bet. It needs you to keep betting at its price.