Environmental impacts of traditional pig production using local breeds are poorly documented. Most studies do not include in their perimeters emissions associated with grazing (EGr) or acorn consumption, or potential carbon sequestration in soils (SeqC). The aim of the present study was to estimate through Life Cycle Assessment (LCA) impacts of traditional pig production in Europe according to four perimeters: Std (standard perimeter), Std + EGr, Std + SeqC, Std + EGr + SeqC. Forty-eight on-farm surveys were conducted in the framework of the TREASURE project (www.treasure.kis.si) to collect the data needed: 25 farms in France (raising Gascon pigs: GAS), 8 farms in Italy (Mora romagnola pigs: MOR), and 15 farms in Slovenia (Krškopolje pigs: KRS). In Std, the climate change (CC) impact per kg live weight at farm gate was lower in KRS than in MOR and GAS (5.85, 7.45 and 7.48 kg CO2-eq, respectively) due to lower environmental impacts of feeds (including co-products obtained on farm) and a better feed conversion ratio of pigs raised indoors. Impacts per ha of land use were lower on GAS farms due to a larger grazing area allocated to the outdoor pigs. In the perimeter Std + SeqC, CC decreased on average by 4%. In the perimeter Std + EGr, CC increased on average by 2%. EGr and SeqC contributed little to the impacts or the reduction in impacts. Hotspots to reduce environmental impacts of traditional pig production include feed composition, decreasing feed distribution to grazing animals, and the origin of feed ingredients.