The Smarkets betting exchange allows you to back and lay with the best betting odds and lowest commission on all major sports and politics. The Betfair Exchange allows you the opportunity to back and lay bets and Cash Out. We also offer Casino, Poker, Games and Bingo. Cricket · Football · Horse Racing · Special Bets. A betting exchange is a marketplace for customers to bet on the outcome of discrete events. Betting exchanges offer the same opportunities to bet as a.