20c839e6_miles___Blog___Airfarewatchdog__3
[0] American [1] "Except as otherwise explained below, mileage credit is not transferable and may not be combined among AAdvantage members, their estates, successors and assigns. Accrued mileage credit and award certificates and award tickets do not constitute property of the member. Neither accrued mileage, award certificates or tickets are transferable by the member (i) upon death, (ii) as part of a domestic relations matter, or (iii) otherwise by operation of law. However, American Airlines, in its sole discretion, may credit accrued mileage to persons specifically identified in court approved divorce decrees and wills upon receipt of documentation satisfactory to American Airlines and upon payment of any applicable fees." [2] Transfer up to 100,000 miles for $10 per thousand (although the first 5,000 miles has a higher price of $20 per thousand). You'll also pay a $35 per transaction processing fee, and transfer a max of 100,000 miles per calendar year. [4] An uncertified copy of the death certificate must also be sent to the airline for proof. No fee required making this one of the more lenient and generous policies. [3] 
It may take a few call transfers to get to this answer, but in-the-know agents can send an affidavit for the beneficiary to be completed and signed by the surviving spouse, sole heir, or executor of the estate. An uncertified copy of the death certificate must also be sent to the airline for proof.
Inheriting frequent flyer miles - Blog - Airfarewatchdog
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