Barangay San Mateo Sur

Barangay San Mateo Sur forms part of San Joaquin, a municipality in Iloilo, and is classified as a very small barangay.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay San Mateo Sur had a population of 164. This made it the 82nd largest of 85 barangays in San Joaquin by population, placing it among the smaller barangays of the municipality. Residents of Barangay San Mateo Sur accounted for approximately 0.31% of the total population of San Joaquin, which stood at 52,617 in the same census year.

Census comparisons between 2015 and 2020 show Barangay San Mateo Sur moving from 152 residents to 164 residents, an intercensal change of +7.9%. The trajectory indicates a growing community. The Philippine Statistics Authority classifies Barangay San Mateo Sur as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

San Joaquin is a municipality comprising 85 barangays, and serves as the governing unit directly responsible for local services in Barangay San Mateo Sur, including public health, sanitation, peace and order, and civil registration. Within the wider province of Iloilo, which contains 1,901 barangays across its component cities and municipalities, Barangay San Mateo Sur ranks 1695th by 2020 population. Iloilo is classified as a 1st by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

The barangay's legislative and executive affairs are handled by a Punong Barangay and the Sangguniang Barangay, elected nationwide during the Barangay and SK Elections. The next BSKE is scheduled for Monday, November 2, 2026, following the synchronized election schedule set by COMELEC Resolution No. 11191.