Not to be confused with Bangkok Metropolis, which is a reference to Bangkok's city limits.
The Bangkok Metropolitan Region (Thai: กรุงเทพมหานครและปริมณฑล; RTGS: Krung Thep Mahanakhon Lae Parimonthon; Literally: Bangkok and surrounding provinces), may refer to a government-defined "political definition" of the urban region surrounding the metropolis of Bangkok, or the built-up area, i.e., urban agglomeration of Bangkok, Thailand, which varies in size and shape, and gets filled in as development expands.
The political definition is defined as the metropolis and the five adjacent provinces of Nakhon Pathom, Pathum Thani, Nonthaburi, Samut Prakan, and Samut Sakhon.
The Bangkok Metropolitan Region (political definition) covers an area of 7,761.6 km².
Due to the success of the service and tourism industry in Bangkok, the city has gained in popularity for work among provincial Thais from the rural areas and with people from many countries in the Indochina region as well as many South Asian countries. In the past 20–30 years, there has been a large influx of Indians in to Thailand (especially Punjabis, Gujaratis, Tamils and Pashtuns), and also Persians, Portuguese, Khmer Krom, Mons, Chinese, as well as others emigrating to Thailand and Bangkok. There are large numbers of workers who legally reside outside the metropolitan area and travel into the city for day jobs. The population of the Bangkok metropolis ("the city") increases to nine million during the day, from eight million at night. The morning influx into the greater metropolitan region is not very significant, rather the influx is seasonal depending upon crop seasons in the rest of the country.