Grand National betting: Your guide to the best odds, free bets and offers Here, we have direct links to the best new customer offers for the. Free Bets for the Grand National from bookmakers. Betting offers and free bet guide for online Horse Racing and the Aintree Grand National. Free Bets. It is important that you shop around as many of the online bookmakers will have Grand National Special Offers to entice you to bet with them. There are no offers.