St. John the Baptist Parish (SJBP, French: Paroisse de Saint-Jean-Baptiste) is a parish located in the U.S. state of Louisiana. At the 2020 census, the population was 42,477. The parish seat is Edgard, an unincorporated area, and the largest city is LaPlace, which is also unincorporated. St. John the Baptist Parish was established in 1807 as one of the original 19 parishes of the Territory of Orleans, which became the state of Louisiana. St. John the Baptist Parish is part of the New Orleans–Metairie metropolitan statistical area.