Get a FREE 4 Pack of Boost Calorie Smart Drink Mailed Coupon! *This offer is still available if you may have missed this. Coupon for one (1) free 4-pack of BOOST CALORIE SMART® 100 Calories Nutritional Drink up to $8.99. While supplies last. Offer available in the U.S. only. Limit one coupon per name, address or household. Allow 2–4 weeks for delivery.