Coupon codes are vouchers that some casinos hand out during campaigns and special occasions. There might for example be a code from a casino on the net or in a magazine and you can use that Coupon Code when creating an account at the casino. Usually there is a field in the registration form where you fill in your voucker code. If you already have an account, you can usually go into a special voucher page where you can enter the code. You usually find that page under My account or in connection with a deposit. Coupons can also be distributed in magazines and news papers in connection with special promotions.