A method for manufacturing a capsule for smoking articles. The capsule includes: a longitudinal development axis, a side wall having a predetermined dimension, a lower end edge and an upper end edge, a bottom, an opening to allow the introduction of a product, and a closing element arranged to close the opening. The method includes the steps of: a) providing the side wall of the capsule; b) filling the capsule with a product; c) determining an amount of product to be introduced into the capsule before step b); and d) arranging the bottom and/or the closing element at a definite distance from the lower end edge and/or the upper end edge based on the quantity of product determined in step c).