I've never had a card that earned miles before so this is all new to me. Last week when I was about to book a flight with US air I was tempted by their 50k bonus miles. I googled and found a link to apply and wave the annual fee the first year. I was approved and have been waiting until my new card comes in the mail to book our flights. It should be here any day. In the meantime, I have found flights with SW that are less expensive and better times. I'm thinking I may have made a mistake by jumping the gun with US Air. Maybe i should have checked out SW Cc instead. If the US Air card comes and I don't activate it will this affect my credit? Should I try to do SW card too? Or just book SW this time and still attempt to rack up my bonus miles on US Air card for next time?