Seixal is a Portuguese city and municipality located in the district of Setúbal within the metropolitan area of Lisbon. It covers an area of 93.58 square kilometres and consists of six parishes, with a recorded population of 184,269 as of 2011.
The municipality is situated across the Tagus River estuary from Lisbon. Its seat is the city of Seixal, which has a population of 31,600 and is positioned along the Rio Judeu.