Dunkin' is giving away 1 million free coffees to customers Thursday, kicking off a stretch of promotions and collaborations tied to National Coffee Day that has already drawn long lines at some locations earlier this week.

Through the limited-time promotion, the coffee and donut chain will give away free hot or iced coffee to the first 1 million customers who claim the offer Thursday, September 24. Dunkin' plans to reveal the specific promo code needed to redeem the offer on its social media accounts midday Thursday. Customers can then enter that code in the "Offers & Rewards" section of the Dunkin' app to claim their free coffee, with the offer redeemable through Sunday, September 27.

Food influencer Snackolator offered advice for customers hoping to secure the freebie before it runs out, emphasizing the importance of preparation ahead of the promo code's release. "Make sure you have the Dunkin' app and an account set up early to grab it quickly – they tend to last a good 30-45 minutes, but the app runs slow, so if you don't sign up ahead of time, it can be tough to do it when it goes live!" the influencer........

© International Business Times