Checked the miles paperwork when I got home and sure enough the 6 month requirement is right there on the receipt for the 10000 miles on the personal account. The business acct however has no such requirement listed (at least that I can find) Ill probably take my chances in closing it after the miles post. Worst case, If they try to charge me a fee for it, Ill have to complain a little bit since my daily spend goes to a chase card.