Sumowo Sejny County
 Sumowo [suˈmɔvɔ] is a village in the administrative district of Gmina Sejny within Sejny County Podlaskie Voivodeship in north-eastern Poland close to the border with Lithuania. It lies approximately 6 kilometres (4 mi) south-west of Sejny and 108 km (67 mi) north of the regional capital Białystok.