Betting exchanges: back and lay

A bookmaker is a shop. An exchange is a room of other punters. You can back a name — hope it wins — or lay it — hope it loses — and the person on the other side is another customer. The house takes a cut when you leave the market richer. That cut is commission. It is not 5/2. It is a percentage of the profit. The shop wears a price. The room wears a percentage. Do not ask them to swap hats.

Worked lay. A horse is 4/1. You lay £10. If it loses you keep the £10 (minus commission on that profit). If it wins you pay 4 × £10 = £40 plus the stake matching, which is why a lay of a short price is a large liability. You have become the book for one name, for one race, for as long as the money is matched. The back and lay sheet lets you back in fractions and lay in decimal in the same row. Put the commission rate on the commission sheet. The sheet will not flatter you. It will tell you what the room already knows.

Betfair, BetDAQ, Matchbook and Smarkets are the four names on that sheet. Ordinary consumer rates come off net winnings in the market, not off the stake, and not once a month. Pro and Select products that also tax losers are spelled out in the commission article. Read it before you type 1% into a box and call yourself a professional. This desk has watched that joke land.

Laying is not spreading. Spreading is buying a number from a firm. Laying is being the book for another punter in the room. One is a quote with two ends. The other is a customer who thinks your 4/1 is wrong. Different rooms. Different arithmetic. Same Saturday if you are not paying attention.