Comparing city populations always comes with a methodological challenge: should the count include only residents within the city's administrative boundaries, or the entire metropolitan area that is economically and socially integrated with it?
Jakarta (Indonesia), for example, has a population of around 10.7 million if only the administrative area of Jakarta is counted. However, if the metropolitan area encompassing Bogor, Depok, Tangerang, and Bekasi is included, the population is much larger.
For this reason, this list uses metropolitan populations or urban agglomerations, rather than the populations of core cities alone. For the top four cities, the figures are based on the World Urbanization Prospects 2025 report published by the United Nations Population Division. The other six cities use official metropolitan-area data from statistical agencies and governments in their respective countries.
Based on this approach, here are the 10 most populous cities in Southeast Asia.
1. Jakarta, Indonesia
Jakarta has a metropolitan population of around 41.9 million, according to World Urbanization Prospects 2025. This makes Jakarta the most populous urban area in Southeast Asia and puts it ahead of Tokyo in the report's global ranking.
The figure is significantly higher than the population of Jabodetabek based on the previous administrative approach, which was recorded at around 31.24 million in the 2020 Population Census.
The difference is partly related to the change in methodology used by the UN Population Division. World Urbanization Prospects 2025 uses the Degree of Urbanization approach, which identifies urban areas based on built-up density and geospatial data, rather than administrative boundaries alone.
2. Metro Manila, Philippines
Metro Manila has a population of around 24.7 million according to World Urbanization Prospects 2025, making it the second-largest urban area in Southeast Asia.
Administratively, Metro Manila, or the National Capital Region, consists of 16 cities and one municipality, covering an area of around 620 square kilometers. The Philippine Statistics Authority (PSA) recorded around 14 million residents in the region in the 2024 Population Census.
The difference between the two figures mainly comes from the geographic coverage used. The 24.7 million figure represents the urban agglomeration population under the World Urbanization Prospects methodology, while the figure of around 14 million refers to residents within the administrative boundaries of the National Capital Region.
3. Bangkok, Thailand
The Bangkok metropolitan area has a population of around 18.2 million according to World Urbanization Prospects 2025.
Under the Thai government's definition, the Bangkok Metropolitan Region includes Bangkok and five surrounding provinces: Nonthaburi, Pathum Thani, Samut Prakan, Samut Sakhon, and Nakhon Pathom.
With this coverage, Thai government data records around 17.4 million residents in the Bangkok metropolitan area. This is equivalent to around one-quarter of Thailand's total population.
4. Ho Chi Minh City, Viet Nam
The Ho Chi Minh City metropolitan area has a population of around 14.1 million according to World Urbanization Prospects 2025, making it the largest urban area in Viet Nam and putting it ahead of Hanoi.
The figure of 14.1 million is also close to the official population of Ho Chi Minh City following the administrative changes in 2025. On June 12, 2025, Viet Nam approved the merger of Ho Chi Minh City with Binh Duong Province and Ba Ria-Vung Tau Province.
The new administrative unit retained the name Ho Chi Minh City and took effect on July 1, 2025. Following the merger, Ho Chi Minh City has an area of 6,772.59 square kilometers and an official population of 14,002,598.
5. Surabaya, Indonesia
The Gerbangkertosusila metropolitan area had around 10.18 million residents in mid-2025. The name Gerbangkertosusila refers to the six areas that make up the region: Gresik, Bangkalan, Mojokerto, Surabaya, Sidoarjo, and Lamongan.
Surabaya serves as the center of the region, with a population of around 3 million. Beyond the core city, urban development also extends into Gresik and Sidoarjo, which are closely connected to Surabaya.
With a population of around 10.18 million, Gerbangkertosusila is Indonesia's second-largest metropolitan area after Jabodetabek.
6. Greater Kuala Lumpur, Malaysia
Greater Kuala Lumpur, also known as the Klang Valley, has around 8.8 million residents. The area is centered on Kuala Lumpur and encompasses connected urban areas in Selangor and Putrajaya.
However, there is no single administrative boundary universally used to define Greater Kuala Lumpur. Broader definitions may include the entirety of Selangor as well as parts of Negeri Sembilan, Pahang, and Perak. As a result, the population figure for the area can vary depending on the boundaries used.
Kuala Lumpur itself has around 2.1 million residents. The much larger metropolitan population shows how extensively the urban area has developed beyond the capital's administrative boundaries.
7. Hanoi, Viet Nam
Hanoi had an average population of around 8.72 million in 2024, based on data from the Hanoi Statistical Office. This makes it the second-largest city in Viet Nam after Ho Chi Minh City.
Hanoi's large population is also related to the size of its administrative area. In 2008, Hanoi was expanded through a merger with the former Ha Tay Province, meaning the capital's administrative area encompasses a much larger region than the city center.
Unlike Ho Chi Minh City, Hanoi was among the 11 cities and provinces that were not merged as part of Viet Nam's administrative restructuring in 2025.
8. Bandung Raya, Indonesia
Bandung Raya is Indonesia's third-largest metropolitan area, with a population of around 8.5 million.
The area includes Bandung City and Cimahi City as its urban centers, as well as Bandung Regency, West Bandung Regency, and Sumedang Regency.
Bandung is the main center of the region. Urban activity then connects with surrounding areas, forming a metropolitan area that is much larger than the population of Bandung City alone.
9. Yangon, Myanmar
Yangon had around 7.4 million residents based on the 2024 provisional census data. This figure represents around 14.4 percent of Myanmar's total population of 51.3 million.
Of the population of Yangon Region, around 68 percent live in urban areas. Yangon remains Myanmar's largest city even though the country's capital was moved to Naypyidaw in 2005.
10. Singapore
Singapore has a different characteristic from the other cities on this list because it is a city-state. The country's territory itself forms a single urban area.
Singapore's urban population reached around 6 million in 2024, based on the World Bank's urban population estimates using UN data. With an area of around 734 square kilometers and almost all of its population living in urban areas, Singapore is essentially a single urban entity.
