The deal comes in Wendy's new Boo Book. It’s a coupon book with five coupons for a free Frosty, and the whole thing only costs a buck. That dollar is donated to the Dave Thomas Foundation for Adoption, a non-profit focused on finding permanent homes for kids in foster care.
The coupon book can be purchased at locations across the country until October 31 and must be used before January 31, 2019. Fortunately, unlike many of the chains other recent deals, you don't have to do anything with the mobile app.