Please correct my math if it's wrong.... Parents each have 150,000 Amex MR points. Neither has ever transferred to DL. With the current 50% bonus http://dmn.delta.com/ace_offers/junemr/ they could each transfer and end up with 225,000 SM and Silver status for $90 each. Delta is also offering a 100% transfer bonus between SM accounts and you can transfer up to 150,000 miles per person per year. https://www.delta.com/skymiles/buy_transfer/transfer_miles/transfer_miles_lto/index.jsp If they both transferred 150k to the other they would each end up with 300k from that transfer, plus the remaining 75,000 from the Amex transfer for a total of 375,000 SM each. Delta charges a fee of $0.01 per mile transferred plus a $30 fee so each transfer of 150,000 miles would cost $1530. The grand total for these transactions would be $3240 and together they would have 750,000. Worth it??