What is the width of the opening of the 1.8L bottle? Lucy November 12, 2020 15:19 Updated The inner width of the mouth of the 1.8L bottle is 4.7cm and the outer width is 4.9cm. Please see diagram below: Related articles Why is my Chilly's Bottle rattling? What are the sizes and weights of Chilly's Bottles? How best to use my Chilly's Bottle? Can Chilly's Bottles keep drinks hot? Are Chilly's Bottles leak-proof? Comments 0 comments Article is closed for comments.