Barangay San Nicolas West

Barangay San Nicolas West forms part of Agoo, a municipality in La Union, and is classified as a mid-sized barangay.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay San Nicolas West had a population of 2,741. This made it the 1st largest of 49 barangays in Agoo by population, placing it among the most populous barangays of the municipality. Residents of Barangay San Nicolas West accounted for approximately 4.15% of the total population of Agoo, which stood at 66,028 in the same census year.

The barangay recorded 2,710 residents in the 2015 intercensal count and 2,741 residents in the 2020 Census — a net change of +1.1%, consistent with a slowly expanding settlement. The Philippine Statistics Authority classifies Barangay San Nicolas West 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 Nicolas West, 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 Nicolas West ranks 51st 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 Nicolas West 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.