However, there is a catch....you have to order a burger from GBK on Deliveroo to be given the option of adding the free milkshake from the famous burger restaurant.
Customers can choose from strawberry, vanilla, chocolate, banana, lime, matcha and salted caramel, which are all made with Yeo Valley ice cream.
The offer runs from now (noon, Thursday, July 20,2017) until 11.45pm.
A spokesperson for Deliveroo added: “If you’re buying a burger today then begin your descent into the weekend with one of the amazing milkshakes from our friends at GBK. With restaurants all across the country taking part we hope we can leave the whole nation shaken not stirred…”