Based on the results of the National Population and Housing Census, Tehran, with a population of 8 million 693 thousand 706 people alone is home to 14.7 percent of the nation’s total population. According to the results, the cities of Tehran, Mashhad, Esfahan, Karaj, Shiraz, Tabriz, Qom and Ahvaz, are the eight metropolitan cites, with a population of over one million people. Kermanshah which is also located near the border, with a population of 946 thousand 651 persons has the highest chance to turn into a metropolitan city in the next Census.

After Tehran, Mashhad as the capital of Khorasane-Razavi province is the most populated Iranian city.  According to the National Population and Housing Census conducted in the year 1395[1], this city had a population of 3001184, followed by  the cities of Esfahan, Karaj, Shiraz, Tabriz, Qom and Ahvaz with the populations of 1961260, 1592492, 1565572, 1558693, 1201158 and 1184788 respectively.

The results of the National Population and Housing Census carried out in the year 1390 also illustrate that in that year like the year 1395, there were only 8 cities with a population of over one million, considered as metropolitan cities. In the year 1390, Tehran, Mashhad, Esfahan with populations of 8154051, 2749374, 1756126 persons, respectively were the most populous cities followed by Karaj (the newly established province), Tabriz, Shiraz, Ahvaz and Qom with populations of 1614626, 1494998, 1460665, 1112021 and 1074036, respectively. 

The review of the metropolitan cities between the years 1390 and 1395 represents that over these five years, Shiraz has become more populous than Tabriz and Qom outnumbered Ahvaz.  Indeed Shiraz and Qom went up in one rank in this respect.          

Close to 36.2% of Iran’s urban population lived in these eight cities in the year 1390 which decreased to 35.1 percent in the year 1395.

A review of the contribution of the metropolitan cities to the urban population in the year 1390 indicates that a total of 25.8% or nearly a quarter of country’s population lived in these metropolitan cities. This proportion in the year 1395 had a little growth and reached 26 percent.

In the year 1395,  there were 1242 cities in the nation where the  eight cited metropolitan cities made up 35 percent of the urban population, and 65 percent of urban population were residing in 1234 cities.

Comparing the population proportion of each metropolitan city to the total population of metropolitan cities in the year 1395 discloses that Tehran alone is home to 41.9% of the country’s urban population, followed by Mashhad (14.5%) and Isfahan (9.4%).

 The National Population and Housing Census outcomes also indicate that the least populated towns in Iran in the year 1395 were Sumar in Kermanshah Province with 180 people; Balavah in Ilam with 264 people, Gazanak  and Ferim in Mazandaran with 319 and 369 persons , Masoule in Gilan province with 455 people, Nik Pay in Zanjan province with 455, Chenare and Babareshani in Kurdistan province with 455 and 509 people, Khezerabad in Yaz province with 535 people and Garab Sofla with  545 people.

Reviewing the ten least populated towns in the country in the year 1395 represents   that these 10 towns in all account for only 0.01 percent of Iran’s urban population; whereas Tehran alone is home to 14.7 percent of urban population. 

Such an unbalanced distribution in urban population has different factors. The transformation of some villages with rural texture to the city is one of the causes; however, in urban population issue, migration issue should not be ignored.