We fly Hawaiian Airlines often. One-way inter-island tickets are 5,000 HA miles. I don't know where the previous poster came up with the 10,000 miles figure. It does cost 10,000 miles for a first class one-way ticket, but not for economy. (In my opinion, unless you have miles or money to burn, it is not worth paying extra for the very short inter-island first class seats.) We have also transferred American Express rewards points to our HA miles accounts with no problems.