20c839e6_miles___Blog___Airfarewatchdog__3
[0] US Airways [1] "All outstanding mileage may be transferred to the estate of a member upon a member's death, after production of appropriate documentation such as a death certificate and proof of beneficiary within one year of the member's passing. Miles cannot be transferred if the deceased member's account has been inactive for more than 36 months at the time of the member's passing. Mileage may not be transferred to any other person except pursuant to these rules. " [2] 1 cent per mile plus a $30 processing fee. 50,000 miles maximum per transaction [4] Death certificate and proof of beneficiary like a will [3] 
As long as you send a copy of the death certificate and will - or another document proving you're the beneficiary - within one year of the death, there's no maximum number of miles and no fee for transferring them.
Inheriting frequent flyer miles - Blog - Airfarewatchdog
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