Starbucks has a pretty sweet deal for National Iced Tea Day — literally! Starbucks has a pretty sweet deal for National Iced Tea Day — literally! What do we love more than food-based holidays? Food-based holidays with free samples. National Iced Tea Day is on Friday, and we know exactly where we’re celebrating: Starbucks. When you buy one iced tea on June 10th, you’ll get one free at participating locations! Starbucks may be known for their inventive coffee creations, but they also have some delicious Teavana teas. What better day to try them than National Iced Tea Day?