<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by ALadyNCal:
I know some things qualify for double miles on Delta all the time (like drug stores). Does COSTCO qualify?</font>
Sorry for the late reply on this one. First of all, I'm assuming that stores that count double on AMEX MR will also count double on Amex DL - I think that's a fairly safe assumption.
Normally I only use my MR card for those charges which I know are always-double-points, but once in a while I'll test someone new (I've had a couple of pleasant surprises). Last month I put a Costco and Target (a Super Target - with a grocery store) charge on my MR card - everything else I knew qualified for 2X treatment. My MR increase for the month was 154 points short of double my total credit card charges - which equaled the total of my Costco and Target charges.
This is the only way I've ever been able to know for sure which questionable charges qualify.