According to the 2020 Census of Population and Housing (2020 CPH), Isabela province's population was 1.697.050 on May 1, 2020, excluding Filipinos in Philippine embassies, consulates, and missions overseas.
In 2020, the province of Isabela had a population density of 130 persons per square kilometer, with a total land area of 13,102.05 square kilometers. This represents an increase of 8 persons per square kilometer from a population density of 122 people (6.5 percent) per square kilometer in 2015. In 2010, 114 people lived on each square kilometer of land.
The population counts are based on the findings of the 2020 CPH. At the national level, only the population living in the Philippine territories were considered in determining population density, or the number of people per square kilometer of land. As a result, Filipinos working in Philippine embassies, consulates, and missions abroad were not included in the total population. Meanwhile, the land areas were determined using the 2013 Masterlist of Land Areas of Cities and Municipalities which was provided by the Land Management Bureau (LMB) to the Philippine Statistics Authority (PSA).
With 158,218 people, the City of Ilagan was the largest of the two component cities, one independent component city, and 34 municipalities that make up the province of Isabela in terms of population. The cities of Santiago (148,580 people) and Cauayan (143,403 people) came in second and third, respectively. With a population of 3,977 inhabitants, the municipality of Maconacon has the smallest population.
The province's largest cities/municipalities in terms of land area were San Mariano with 1,459.16 square kilometers, City of Ilagan with 1,166.26 square kilometers, and three coastal towns, Dinapigue with 1,031.93 square kilometers, Divilacan with 889.49 square kilometers, and Palanan with 880.24 square kilometers. With a land area of 44.94 square kilometers, Luna was the smallest municipality.
The number of persons per square kilometer of land is referred to as "population density." The City of Santiago was the most densely populated of Isabela's cities/ municipalities, with a population density of 582 people per square kilometer. This represents an increase of 54 individuals per square kilometer (10.2 percent) over the 528 people per square kilometer reported in 2015. In 2010, the population density per square kilometer was 520 persons per square kilometer.
In 2020, there were 28 cities/municipalities with a population density of more than 100 people per square kilometer, accounting for more than 76 percent of the province's total number of cities/municipalities.
With a population density of 136 persons per square kilometer, the City of llagan was the country's least densely populated component city. The City of Santiago with 582 inhabitants per square kilometer was rated fourth among the five independent component cities in the Philippines in terms of population density.
With 583 inhabitants per square kilometer in 2020, the City of Santiago was the most densely populated of the three cities and 34 municipalities in the province of Isabela. Completing the top ten most densely populated municipalities were Cabatuan with 555 people per square kilometer, Reina Mercedes with 488 people per square kilometer, Alicia with 749 people per square kilometer, Roxas with 470 people per square kilometer, Luna with 461 people per square kilometer, City of Cauayan with 426 people per square kilometer, and the municipality of Alicia with 749 people per square kilometer.
The Municipality of Dinapgue, on the other hand, has the lowest population density in the province, with only 6 people per square kilometer. Divilacan and Maconacon, with 7 people per square kilometer, Palanan, with 20 people per square kilometer, San Mariano and San Pablo, with 41 people per square kilometer, San Guillermo, with 46 people per square kilometer, Jones, with 68 people per square kilometer, and San Agustin, with 79 people per square kilometer, rounded out the top ten most sparsely populated municipalities in the province.
JULIUS M. EMPERADOR
Chief Statistical Specialist