Poszeszupie [pɔʂɛˈʂupjɛ] is a village in the administrative district of Gmina Rutka-Tartak, within Suwałki County, Podlaskie Voivodeship, in north-eastern Poland, close to the border with Lithuania. It lies approximately 31 kilometres (19 mi) north of Suwałki and 138 km (86 mi) north of the regional capital Białystok.