Joniec-Kolonia [ˈjɔɲɛt͡s kɔˈlɔɲa] is a village in the administrative district of Gmina Joniec, within Płońsk County, Masovian Voivodeship, in east-central Poland. It lies approximately 13 kilometres (8 mi) east of Płońsk and 52 km (32 mi) north-west of Warsaw.