Barangay San Joaquin Sur

Classified as a small barangay, Barangay San Joaquin Sur is one of the administrative divisions of Agoo in La Union, Ilocos Region, Philippines.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay San Joaquin Sur had a population of 1,506. This made it the 16th largest of 49 barangays in Agoo by population, placing it in the middle tier of the municipality. Residents of Barangay San Joaquin Sur accounted for approximately 2.28% of the total population of Agoo, which stood at 66,028 in the same census year.

Between the 2015 and 2020 censuses, the population of Barangay San Joaquin Sur changed from 1,480 to 1,506, a shift of +1.8% over the five-year period. This places the barangay among those with slowly expanding populations in Agoo. The Philippine Statistics Authority classifies Barangay San Joaquin Sur as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Agoo is a municipality comprising 49 barangays, and serves as the governing unit directly responsible for local services in Barangay San Joaquin Sur, including public health, sanitation, peace and order, and civil registration. Within the wider province of La Union, which contains 576 barangays across its component cities and municipalities, Barangay San Joaquin Sur ranks 191st by 2020 population. La Union is classified as a 1st by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

Like every Philippine barangay, Barangay San Joaquin Sur is led by an elected Punong Barangay (barangay captain) supported by seven Sangguniang Barangay members (kagawads), an SK Chairperson, a Barangay Secretary, and a Barangay Treasurer. The next Barangay and Sangguniang Kabataan Elections (BSKE) are scheduled for Monday, November 2, 2026, with officials serving four-year terms under Republic Act No. 12232.