Agoncillo, officially the Municipality of Agoncillo, is a municipality in the province of Batangas, Philippines. According to the 2020 census, it h…Agoncillo, officially the Municipality of Agoncillo, is a municipality in the province of Batangas, Philippines. According to the 2020 census, it has a population of 39,101 people. The town was named in honor of Don Felipe Agoncillo, a native of Taal and one of the first Filipino representatives to the Spanish Cortes.