Ślubowo [ɕluˈbɔvɔ] is a village in the administrative district of Gmina Sońsk, within Ciechanów County, Masovian Voivodeship, in east-central Poland. It lies approximately 8 kilometres (5 mi) south of Sońsk, 19 km (12 mi) south-east of Ciechanów, and 59 km (37 mi) north of Warsaw.