Also known as: Lalawigan ng Isabela
Isabela is a province in Region II (Cagayan Valley). Population 1.73M (PSA 2024 census), 2 component cities + 34 municipalities, 1,055 barangays total, land area 13,102.05 km². Provincial capital: Ilagan (City of Ilagan — not Santiago City, which is an independent component city, administratively separate from the province).
Isabela is a province in Region II (Cagayan Valley). Its capital is Ilagan (City of Ilagan — not Santiago City, which is an independent component city, administratively separate from the province).
Isabela had 1,733,048 residents in the 2024 census (PSA 2024 Census of Population (POPCEN 2024), reference date July 1, 2024). That is the most recent official count. There is no 2026 census result, so any 2026 population figure is an estimate.
Isabela covers 13,102.05 km², per the PSA Philippine Statistical Yearbook figure used on this page.
Isabela has 2 component cities and 34 municipalities (36 LGUs under the province), per PSA's Philippine Standard Geographic Code (2Q 2026), and 1,055 barangays. Santiago City is an independent component city located within Isabela, outside the province's supervision, so it is not counted above; counting it, there are 3 cities in all.
Isabela's 2 component cities are Cauayan City and Ilagan City. Its 34 municipalities are Alicia, Angadanan, Aurora, Benito Soliven, Burgos, Cabagan, Cabatuan, Cordon, Delfin Albano, Dinapigue, Divilacan, Echague, Gamu, Jones, Luna, Maconacon, Mallig, Naguilian, Palanan, Quezon, Quirino, Ramon, Reina Mercedes, Roxas, San Agustin, San Guillermo, San Isidro, San Manuel, San Mariano, San Mateo, San Pablo, Santa Maria, Santo Tomas and Tumauini. Santiago City is an independent component city located within Isabela, outside the province's supervision, so it is not counted above; counting it, there are 3 cities in all.
Isabela is the second-largest province in the Philippines by land area, stretching from the Sierra Madre mountain range on its eastern edge across the Cagayan River valley toward the Cordillera foothills in the west. That size, combined with genuinely fertile floodplain soil, has made it the country's top corn-producing province — it accounts for roughly 13% of national yellow corn production — and a nationally recognized rice producer. Agriculture isn't a side note here; it's most of the provincial economy, supplemented by agricultural trading and processing concentrated in Cauayan.
The province's east side includes the Palanan Wilderness, one of the largest remaining lowland rainforest areas in the Philippines, shielded somewhat from development by the Sierra Madre's terrain — but that same mountain range funnels typhoon rainfall directly into the Cagayan River system running the length of the province. The 2020 typhoon season made the risk concrete: Typhoon Vamco (Ulysses) forced Magat Dam to release a large volume of water into the Cagayan River, and the resulting flooding hit riverside towns across Isabela. Flood-hazard mapping along the river isn't a hypothetical planning exercise for the province — it's a recurring, near-annual concern.
What makes provincial coordination genuinely complex in Isabela, though, is that the province doesn't have one obvious urban center — it has three. Ilagan, converted to a component city in 2012, holds the provincial capitol and is the seat of government. Cauayan, also a component city, has grown into the province's commercial and banking hub, hosting SM City Cauayan and the proposed site for the Isabela Special Economic Zone and a regional agro-industrial growth center. Santiago, the province's most populous city, is an independent component city entirely outside provincial government, chartered in 1994 out of Isabela's own southern territory. Coordinating land-use planning, infrastructure investment, and disaster-response priorities across three separate centers of gravity — one of which the province doesn't even govern — is a different shape of problem than the single-dominant-city pattern seen in many other Philippine provinces.
Key industries: Corn (top corn-producing province nationally), Rice / palay production, Agricultural trading + processing (Cauayan), Livestock, Forestry (Sierra Madre foothills)
More on the regulatory framework: CLUP explainer · RA 7160 explainer · SGLG explainer · full glossary. Working a CLUP review cycle? Run the CLUP readiness self-check or see CLUP compliance monitoring.
Isabela's provincial planning office coordinates CLUP and disaster-risk work across 34 municipalities and two component cities, spread over the second-largest land area of any Philippine province and split between three real centers of gravity — Ilagan, Cauayan, and the independently governed Santiago. Nova Gov is designed to help a planning office manage that kind of multi-hub complexity, and the pilot program is built to give provinces like Isabela a clearer working view across a large number of LGUs at once.
Isabela's provincial government coordinates land-use and disaster planning across 34 municipalities and two component cities, split between Ilagan, Cauayan, and an independently governed Santiago. If your office needs a clearer working view across that many LGUs, Nova Gov's pilot program is worth a conversation.
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