Barangay Balagtasin I

Classified as a small barangay, Barangay Balagtasin I is one of the administrative divisions of San Jose in Batangas, CALABARZON, Philippines.

According to the 2020 Philippine census, Barangay Balagtasin I had a population of 1,595. This made it the 24th largest of 33 barangays in San Jose by population, placing it in the middle tier of the municipality. Residents of Barangay Balagtasin I accounted for approximately 2.00% of the total population of San Jose, which stood at 79,868 in the same census year.

The barangay recorded 1,399 residents in the 2015 intercensal count and 1,595 residents in the 2020 Census — a net change of +14.0%, consistent with a growing settlement. Barangay Balagtasin I is officially classified as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

San Jose is a municipality comprising 33 barangays, and serves as the governing unit directly responsible for local services in Barangay Balagtasin I, including public health, sanitation, peace and order, and civil registration. Within the wider province of Batangas, which contains 1,078 barangays across its component cities and municipalities, Barangay Balagtasin I ranks 674th by 2020 population. Batangas 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.