Wąsosz [ˈvɔ̃sɔʂ] is a village in Grajewo County, Podlaskie Voivodeship, in north-eastern Poland.

[2] It received Chełmno municipal rights from Duke Władysław I on 13 May 1436, and lost them in 1870 under the Russian rule following the Partitions of Poland.

[2] The Carmelite monastery was closed in 1864 by the Tsarist authorities in reprisal for help offered by monks to victims of the January Uprising.

[3] Following the joint German-Soviet invasion of Poland, which started World War II in September 1939, it was first occupied by the Soviet Union until 1941, and then by Germany until 1944.

[4] One of the most impressive points of interest in Wąsosz is its late Gothic church from 1508, with three altars adorned with religious paintings.