Groupon: $6 For A $10 Voucher To Dunkin Donuts! This post may contain affiliate links. Please see the full disclosure policy here. Posted on November 22, 2013 Written by Kristen Dann 1 Comment Hot deal on Groupon right now! Get a $10 gift certificate to Dunkin Donuts for just $6! That’s like getting $4 for free! Thanks Coupon Cravings!