Barangay Tambunan

Classified as a small barangay, Barangay Tambunan is one of the administrative divisions of Boac in Marinduque, MIMAROPA Region, Philippines.

According to the 2020 Philippine census, Barangay Tambunan had a population of 574. This made it the 40th largest of 61 barangays in Boac by population, placing it in the middle tier of the municipality. Residents of Barangay Tambunan accounted for approximately 1.00% of the total population of Boac, which stood at 57,283 in the same census year.

Between the 2015 and 2020 censuses, the population of Barangay Tambunan changed from 573 to 574, a shift of +0.2% over the five-year period. This places the barangay among those with slowly expanding populations in Boac. Barangay Tambunan is officially classified as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Boac is a municipality comprising 61 barangays, and serves as the governing unit directly responsible for local services in Barangay Tambunan, including public health, sanitation, peace and order, and civil registration. Within the wider province of Marinduque, which contains 218 barangays across its component cities and municipalities, Barangay Tambunan ranks 157th by 2020 population. Marinduque is classified as a 4th by the Bureau of Local Government Finance, a category that reflects the province's annual regular income.

Like every Philippine barangay, Barangay Tambunan 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.