KitKat Chunky Salted Caramel Popcorn will be available from 2 August in a 42g bar, featuring wafer alongside a layer of salted caramel popcorn filling, covered in milk chocolate (70p).
The launch will be supported with social media and out-of-home activity that will also include KitKat Chunky Milk and KitKat Chunky Peanut Butter.
Nestlé said caramel is the most popular milk chocolate variant in the UK, bought by 64% of all UK households.
It said penetration of salted caramel has trebled in the last four years and one in four shoppers have tried a salted caramel product.