Check out the full list of online casinos with each being reviewed and rated in line. Fixed odds & bonus. Deposit and place a bet of £20 and get a free bet of £20 to place on your favorite sports. Looking for the top online casinos, then you are in the right place. Dominican Republic; Anguilla; Antigua and Barbuda; Dominica; Grenada; Montserrat MustardBet Partners; Bona Fides Affiliates; Casollo Affiliates; Hamabet. Find the best free bets in UK. £20 Bonus bet – With Mr Green it is very simple. In the table below, we've listed a range of free offers for our readers. .