The largest city in Thailand is Bangkok, with a population of roughly 10.7 million in its metropolitan area, followed by Chiang Mai (about 1.2 million in its greater region), Nonthaburi (around 270,000), Nakhon Ratchasima, Hat Yai, Udon Thani, Khon Kaen, Pattaya, Chiang Rai, and Phuket City. Thailand is home to roughly 70 million people, and its urban landscape is unusually top-heavy: Bangkok dwarfs every other settlement in the kingdom, while a handful of regional capitals anchor the north, northeast, and south.
Bangkok: A Primate City Like No Other
Bangkok, known to Thais as Krung Thep, is one of the most extreme examples of a primate city in the world. Its metropolitan population of about 10.7 million is more than ten times larger than that of Chiang Mai, the next biggest urban center. Bangkok is the political capital, the financial heart, the main international gateway, and the cultural epicenter of Thailand all at once. Founded as the capital in 1782 by King Rama I, it sits on the Chao Phraya River near the Gulf of Thailand and has grown into a sprawling megacity famous for its temples, floating markets, street food, and relentless traffic. Its full ceremonial name, beginning "Krung Thep Mahanakhon," is recognized as the longest place name in the world at 168 letters.
The Northern Hub: Chiang Mai and Chiang Rai
Chiang Mai is Thailand's second city, with a greater-area population around 1.2 million. Founded in 1296 as the capital of the Lanna kingdom, it remains the cultural and economic center of the mountainous north. Surrounded by a moat and the remains of old city walls, Chiang Mai is renowned for its hundreds of Buddhist temples, cool-season climate, and growing community of digital nomads and creative entrepreneurs.
Further north, Chiang Rai (roughly 80,000 in the city proper) serves as a gateway to the Golden Triangle, where Thailand meets Laos and Myanmar. Though smaller, it is well known for its strikingly modern White Temple (Wat Rong Khun) and its role in regional border trade.
The Northeastern Heartland: Isan's Big Cities
Thailand's northeast, known as Isan, is the country's most populous region and is anchored by several major provincial cities:
- Nakhon Ratchasima (also called Korat), around 170,000 in the city, is the largest gateway to Isan and a key commercial and transport hub.
- Udon Thani, roughly 130,000, grew rapidly during the Vietnam War era as a U.S. air base town and now thrives on trade with neighboring Laos.
- Khon Kaen, about 130,000, is the educational and administrative center of central Isan, home to one of Thailand's leading universities.
These cities are far less internationally known than Bangkok or the beach resorts, but together they form the backbone of Thailand's rural and agricultural economy.
The Suburbs and the Southern Cities
Some of Thailand's most populous municipalities are not standalone cities at all but part of Greater Bangkok. Nonthaburi, with about 270,000 residents, sits directly north of the capital and functions as a dense residential suburb within the Bangkok metropolitan region. Its high population reflects urban sprawl rather than a separate city economy.
In the far south, Hat Yai (around 160,000) is the largest city of the Malay-Peninsula region and a major commercial center close to the Malaysian border, drawing shoppers and tourists from across the frontier. The resort city of Pattaya (roughly 120,000 permanent residents but far more by day) on the eastern Gulf coast and Phuket City (about 80,000) on Thailand's largest island are both globally famous tourism destinations whose daytime and seasonal populations swell well beyond their official figures.
Why Thailand's Population Is So Concentrated
Roughly half of Thailand's population is now classified as urban, and that urbanization is heavily skewed toward Bangkok and its surrounding provinces. Decades of centralized investment, government, and industry in the capital region created a powerful pull, leaving most other cities an order of magnitude smaller. As a result, no single Thai city other than Bangkok comes close to the scale typical of capitals in similarly sized nations. This imbalance shapes everything from migration patterns to infrastructure planning across the kingdom.
Bangkok Dwarfs Everything Else
Thailand has one of the most extreme urban primacy ratios in the world. Bangkok's metropolitan region holds somewhere above ten million people, while the next largest city is smaller by a factor of roughly twenty depending on which figures are used.
Nothing in the country functions as a second city in the way Osaka does for Japan or Busan for South Korea. Chiang Mai in the north, Nakhon Ratchasima in the north-east and Hat Yai in the south are regional centres of a few hundred thousand at most.
The imbalance is a long-running subject in Thai policy debate, and successive plans to develop regional growth poles, most recently the Eastern Economic Corridor around Chonburi and Rayong, have been attempts to address it.
The Capital Has the Longest Name in the World
What foreigners call Bangkok, Thais call Krung Thep. The full ceremonial name, beginning Krungthepmahanakhon Amonrattanakosin and running to 168 Roman characters, is listed by Guinness World Records as the longest place name in existence.
It translates roughly as the city of angels, great city of immortals, and continues through a sequence of titles describing the city as the seat of the reincarnated god. Thai schoolchildren learn it as a song.
Bangkok itself derives from an older name for a district on the river, and it stuck in foreign usage after the capital moved there in 1782, when Rama I founded the Chakri dynasty and built the Grand Palace on the east bank of the Chao Phraya.
A City Built on Canals, Now Sinking
Bangkok was once threaded with canals, the khlongs, and was described by nineteenth-century visitors as the Venice of the East. Most were filled in during the twentieth century to build roads, and only a fraction of the network survives, chiefly on the Thonburi side.
The city sits on soft delta clay barely above sea level, and it is subsiding, driven by groundwater extraction and the weight of construction. Combined with rising seas, the projections are severe enough that relocating the capital has been publicly discussed by Thai officials.
Flooding is already routine. The 2011 floods inundated large parts of the central plain and the industrial estates north of the city for months, disrupting global supply chains for hard drives and car components.
Tourism Built Cities of Its Own
Thailand receives tens of millions of international visitors a year, and several urban areas on and around this list exist substantially because of it. Pattaya grew from a fishing village after it became a rest destination during the Vietnam War; Phuket and Krabi developed around beach tourism from the 1980s.
Chiang Mai, founded in 1296 as the capital of the Lanna kingdom, has a different profile: a walled old city with more than 300 temples, a northern dialect and cuisine, and in recent years one of the largest concentrations of remote workers in Asia.
The 2004 Indian Ocean tsunami struck the Andaman coast, killing more than 5,000 people in Thailand, many of them in Khao Lak and on Phi Phi, and reshaped both the coastline and the warning systems along it.
Isan Is the Population That Moves
The north-east, Isan, holds roughly a third of Thailand's population and is the poorest region. Its language is closer to Lao than to central Thai, and its food and music are distinct enough to be treated as a separate culture within the country.
Isan supplies much of the labour that runs Bangkok: construction workers, taxi and motorbike drivers, market traders and factory staff, many of whom migrate seasonally around the rice calendar and return home for Songkran.
That circulation is why Bangkok's population figures fluctuate and why the official registered count is considerably lower than the number of people actually in the city. It is also the demographic base of the political movements that have contested Thai politics since 2006. Our Thailand country guide covers the regions that movement comes from.
Common Questions About Thai Cities
What is the biggest city in Thailand?
Bangkok is by far the biggest city in Thailand, with a metropolitan population of about 10.7 million. It is the capital and the country's dominant economic, political, and cultural center.
What is the second largest city in Thailand?
Chiang Mai is the second largest city, with around 1.2 million people in its greater area. It is the main hub of northern Thailand and a major cultural and tourism destination.
Is Pattaya or Phuket bigger?
By permanent population, Pattaya (roughly 120,000) is larger than Phuket City (about 80,000). However, both are world-famous resort areas whose populations rise sharply with seasonal tourism.
How many people live in Thailand overall?
Thailand has a total population of approximately 70 million people. Want to test your knowledge of world cities and capitals? Try our interactive geography games.
What is Bangkok's real name?
Krung Thep Maha Nakhon in everyday Thai use, with a full ceremonial name of 168 Roman characters that holds the record for the longest place name in the world. Bangkok is an older district name that foreigners kept using.