AdWeek reported the ban would take effect Saturday and would include electronic cigarettes.
The new rule was receiving mixed reactions from customers, WJXT Jacksonville, Fla., reported.
"I think for them to stop that is a conflict between the two. Everybody knows coffee and cigarettes go hand-in-hand," said one customer, Charli Dirani, who is a smoker.
Dirani said Starbucks would lose business with the new policy.
AdWeek said there had been an online campaign pushing Starbucks to ban cigarette smoking in outdoor areas since 2009.
NPR reported Moms Demand Action for Gun Sense In America is pressing Starbucks to ban loaded guns inside its stores.