I have actually had the opportunity to work with Continental, Delta and United to 'transfer' mileage into a survivor's (spouse) ff account.I anticipated some degree of difficulty but the whole process was relatively smooth. I merely wrote to the airline in question, with a brief outline of the situation at hand, and enclosed a copy of the death certificate (no will required). The miles were transferred within a reasonable period of time and follow-up correspondence was not needed! In one instance, an award ticket in the name of the deceased was even redeposited into the spouse's account. Additionally,I recently spoke with a young lady who was in the process of transferring her late father's mileage into her own NW account: As she was not'next-of-kin,'NW did require sight of the will indicating that she was the designated heir. Hope this helps someone!