How metropolitan areas contribute to population change

Today, half of the OECD population live in metropolitan areas – cities with more than 500 000 people.

Administrative boundaries do not always match up with where people live, work and spend leisure time. Therefore, metropolitan areas are here defined as functional urban areas (FUA) – densely populated cities and commuting zones with high levels of commuting towards the city. There are 1 197 functional urban areas in the 30 OECD countries considered, and 281 of them are classified as metropolitan areas, having a population larger than 500 000 people.

In the last 15 years, the population in metropolitan areas has been growing at a faster rate in the commuting zones rather than in the city centres. The sub-urbanisation is particularly strong in the commuting zones of large metropolitan areas (with more than 1.5 million people). In these areas population grew at a rate of 1.6% while the city centre grew at a rate below 1% (Figure 2.8). In contrast, in small metropolitan areas (with a population between 500 000 and 1.5 million) in Australia, Japan, and Korea the urban population grew at a faster rate in the city centre than in the commuting zone, particularly evident in Japanese cities.

The number of local governments per 100 000 people – a measure of administrative fragmentation of the metropolitan area – varies from around 24 in the Czech Republic to less than 0.5 in Mexico, the United Kingdom, Ireland and Korea (Figure 2.9). On average, municipalities in OECD metropolitan areas concentrate more than 300 000 people.


281 Metropolitan areas have been identified in 30 OECD countries according to the OECD-EU methodology that identifies metropolitan areas on the basis of densely populated cities and their commuting zones (travel to work journeys) to reflect the economic geography of the population’s daily commuting patterns (see Annex A for details).


OECD (2015), “Metropolitan areas”, OECD Regional Statistics (database),

Reference years and territorial level

For lack of comparable data on commuting, the FUAs have not been identified in Iceland, Israel, New Zealand and Turkey. The FUA of Luxembourg does not appear in the figures since it has a population below 500 000 inhabitants.

Further information

OECD (2012), Redefining “Urban”: A New Way to Measure Metropolitan Areas, OECD Publishing, Paris,

Figure notes

 2.8- 2.9: Metropolitan population figures are estimates based on municipal figures for the last two census available for each country.

Information on data for Israel:

2.8. Yearly population growth of metropolitan areas in city and commuting area, 2000-14

2.9. Administrative fragmentation of metropolitan areas, 2014