Barangay Casasahan Ilaya

Barangay Casasahan Ilaya is a very small barangay in the municipality of Gumaca, located in the province of Quezon, in the CALABARZON region of the Philippines.

According to the 2020 Philippine census, Barangay Casasahan Ilaya had a population of 285. This made it the 47th largest of 59 barangays in Gumaca by population, placing it among the smaller barangays of the municipality. Residents of Barangay Casasahan Ilaya accounted for approximately 0.40% of the total population of Gumaca, which stood at 71,942 in the same census year.

Census comparisons between 2015 and 2020 show Barangay Casasahan Ilaya moving from 443 residents to 285 residents, an intercensal change of -35.7%. The trajectory indicates a contracting community. Barangay Casasahan Ilaya is officially classified as rural, a designation applied to barangays with lower population density and predominantly non-built-up land use.

Gumaca is a municipality comprising 59 barangays, and serves as the governing unit directly responsible for local services in Barangay Casasahan Ilaya, including public health, sanitation, peace and order, and civil registration. Within the wider province of Quezon, which contains 1,242 barangays across its component cities and municipalities, Barangay Casasahan Ilaya ranks 1108th by 2020 population. Quezon 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.