Tongkil is a municipality in the province of Sulu.

According to the 2000 census, it has a population of 15,933 people in 2,591 households.

The municipality was renamed Banguingui on January 29, 2006 in honor of the dominant Banguingui tribe of the municipality.

Tongkil is politically subdivided into 14 barangays.

Its climate is warm, humidity is generally moist, but precipitation is constant throughout the year. February is considered the coldest month while May to August are the hottest, with mean relative humidity of 86%, one of the hottest in the country.