Longchamp's partner tanneries use high-performance water treatment systems. Using a circular economy approach, the by-products created during the tanning process are often reused directly by the tannery, or recycled via third parties. Guaranteeing clean and high quality products has always been an essential part of Longchamp's mission. The brand makes every effort to ensure its products are safe and free of any chemicals that could have a harmful effect on its customers' or employees' health. To support its partner tanneries in the environmental certification process, Longchamp draws on the expertise of an independent body, the Leather Working Group. In 2022, 99% of leather purchases by Longchamp were made from tanneries certified by the LWG, 50% of which were Gold certified, the highest level achievable.

Longchamp’s leathers come from animals raised in Europe, Africa, and South America. Longchamp ensures that related livestock farming does not contribute to deforestation, particularly in the Amazon rainforest. These hides are processed by the best tanners in France, Italy, Portugal, Spain, the Netherlands, England, Uruguay, and Brazil.

The House no longer uses exotic species or farmed fur-bearing animals in the manufacture of its collections. Biodiversity, wildlife, exotic species, and endangered animals are a concern for Sophie Delafontaine, Artistic Director, who now prohibits their use in the Longchamp collections. The leathers Longchamp uses to manufacture its products exclusively come from animals, both ovine and bovine, primarily intended for food consumption.