Gromadzyn-Wykno [ɡrɔˈmad͡zɨn ˈvɨknɔ] is a village in the administrative district of Gmina Kolno, within Kolno County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately 3 kilometres (2 mi) south-east of Kolno and 86 km (53 mi) west of the regional capital Białystok.