Seoul’s total population of native South Koreans declined to 9.49 million as of May according to the Ministry of the Interior and Safety. 

Seoul has been widely known as a city of 10 million residents. The population of Seoul first surpassed the 10 million bar in 1988. In 1992, the number of residents in Seoul peaked at 10.97 million. Yet its population started to decline since then, dropping below 9.5 million residents this year.

In 2016, the capital city‘s South Korean population fell under 10 million for the first time to reach 9.99 million.
According to the government-run Seoul Institute, a recent boost of housing supply in Gyeonggi Province has propelled the outflow of residents from Seoul seeking more affordable and bigger housing. Seoul’s low fertility rate has also contributed to this decline as well. 

On the other hand, the population of surrounding Gyeonggi Province is increasing rapidly. As of end-May, the population of Gyeonggi Province reached 13.58 million, around 4 million more than that of Seoul.

South Korea’s statistics agency predicted that the population of Seoul will shrink to 7.2 million in 2050 in a worst-case scenario, down by 25.1 percent from 9.6 million in 2020, while the country’s total population would decrease to 47.3 million, down 8.6 percent from 51.8 million in 2020.

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