Today only, Sep 27, 2015, Dunkin’ Donuts is celebrating National Coffee Day by offering a Medium Hot or Iced Dark Roast Coffee for FREE. Plus, If you are a DD Perks Member, you get an additional beverage for FREE via a coupon in the Dunkin’ Donuts mobile app. Update: 200 points will be added to your account, equating to another FREE any-size coffee or beverage of their choice! The Free beverage will show up as a coupon in the Dunkin’ Mobile App, and can be redeemed any time before the end of the year. No purchase necessary. Limit of one per guest.