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?