Barangay Magallungon (Sta. Teresa)

Classified as a small barangay, Barangay Magallungon (Sta. Teresa) is one of the administrative divisions of Lal-Lo in Cagayan, Cagayan Valley, Philippines.

According to the 2020 Census of Population and Housing conducted by the Philippine Statistics Authority, Barangay Magallungon (Sta. Teresa) had a population of 1,002. This made it the 23rd largest of 35 barangays in Lal-Lo by population, placing it in the middle tier of the municipality. Residents of Barangay Magallungon (Sta. Teresa) accounted for approximately 2.06% of the total population of Lal-Lo, which stood at 48,733 in the same census year.

The barangay recorded 870 residents in the 2015 intercensal count and 1,002 residents in the 2020 Census — a net change of +15.2%, consistent with a growing settlement. The Philippine Statistics Authority classifies Barangay Magallungon (Sta. Teresa) as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Lal-Lo is a municipality comprising 35 barangays, and serves as the governing unit directly responsible for local services in Barangay Magallungon (Sta. Teresa), including public health, sanitation, peace and order, and civil registration. Within the wider province of Cagayan, which contains 820 barangays across its component cities and municipalities, Barangay Magallungon (Sta. Teresa) ranks 515th by 2020 population. Cagayan is classified as a 1st by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

Barangay Magallungon (Sta. Teresa) is governed by an elected Sangguniang Barangay composed of a Punong Barangay and seven kagawads, with the Sangguniang Kabataan representing the youth. The next BSKE, set for Monday, November 2, 2026, will elect officials to four-year terms as provided under Republic Act No. 12232.