Jednaczewo [jɛdnaˈt͡ʂɛvɔ] is a village in the administrative district of Gmina Łomża, within Łomża County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately 8 kilometres (5 mi) north-west of Łomża and 79 km (49 mi) west of the regional capital Białystok.