Make Dunkin' Donuts part of your routine and get rewarded every month! For every 4 times you shop at a Dunkin' Donuts store in a calendar month, you will receive a $5 Dunkin' Donuts card. Simply enroll your Blue from American Express, Blue Cash from American Express or Blue Sky Card and use it to make your purchases. After 4 purchases, we will mail you a $5 DD card. The more you go, the more DD cards you can earn through 3/31/11!