Originally Posted by
nako
...the best way to do it is through the Diners Club program ... which would turn 20,000 AA miles into 10,000 DL miles. If you don't have one, then the best way is through the Hilton HHonors program, which would turn the 20k AA miles into 4,000 DL miles.
It could be worth obtaining a Diners Club card just to perform the transfer, rather than transfer through Hilton. To transfer AA -> Diners -> DL would cost $25. To obtain a Diners Club card would cost $95, but would also earn 1,000 points per month (requires one transaction per month which will earn additional points). That's another 12,000+ Skymiles. Diners charges $0.95 per 1,000 for the transfer.
Total 22,000+ miles for $141 = $0.006 per mile.
Diners Club Rewards is a good program, offering transfer to 20 airlines...
https://www.citibank.com/dinersus/js...egory=fc79feb6
...and seven hotel chains...
https://www.citibank.com/dinersus/js...egory=e350b05d