South Korea's elderly population increased by more than 600,000 over the past year, more than doubling the youth population.

The working-age population fell below 70% for the first time since relevant statistics began.

While the total population remained virtually stagnant, an increase in foreign residents offset the decline in domestic citizens, avoiding an overall population decrease.

The National Data Agency released the results of the 2025 Population and Housing Census containing these findings today (the 28th).

The most prominent change in South Korea's demographic structure last year was the deepening of population aging.

Looking at the total population by age group, including both domestic and foreign nationals, those in their 50s accounted for the largest share at 16.7%, followed by those in their 60s (15.3%) and 40s (14.8%).

The median age stood at 46.8 years, up 0.6 years from a year earlier.

The working-age population, aged 15 to 64, stood at 35.87 million, or 69.2%, falling below 70% for the first time since comparable statistics began in 2015.

The elderly population aged 65 and older reached 10.723 million, or 20.7%, exceeding 20% for the first time.

Conversely, the youth population aged 0 to 14 amounted to 5.225 million, or 10.1%.

While the youth population decreased by 196,000 and the working-age population declined by 393,000, the elderly population increased by 601,000.

The old-age dependency ratio, calculated by dividing the elderly population by the working-age population, rose to 29.9, up 2.0 from the previous year.

This means approximately three people in the working-age population must support one elderly person.

The aging index, which represents the ratio of the elderly population per 100 youths, stood at 205.2, an increase of 18.5 from the previous year.

This is more than twice the size of the youth population.

Along with population aging, changes in marital structures were also distinct.

Among the 43.234 million domestic citizens aged 18 and older, the unmarried population accounted for 29.6%, or 12.789 million people.

Married individuals with a spouse accounted for 56.3% (24.348 million people), while those who were bereaved or divorced made up 14.1% (6.096 million people).

The unmarried population increased by 54,000 from the previous year, and the married population with a spouse grew by 41,000.

Broken down by age group, the unmarried rate for people in their 30s exceeded half at 54.7%.

The rate was 21.9% for those in their 40s, while those in their 20s and younger recorded the highest at 96.0%.

The proportion of people with a spouse was highest among those in their 60s at 75.8%, followed by those in their 50s (74.8%) and 40s (70.7%).

Seoul recorded the highest unmarried rate at 37.1% and the lowest married-with-spouse rate at 51.1%.

The region with the lowest unmarried rate was Jeollanam-do at 22.2%, while Sejong recorded the highest married-with-spouse rate at 64.4%.

Amid demographic shifts such as aging and a decrease in marriages, the total population remained virtually stagnant.

As of November 1 of last year, the total population stood at 51.817 million, an increase of 0.02%, or 12,000 people, from the previous year.

The population growth rate has been slowing down due to the impact of low birth rates.

After declining from 2021 to 2022 in the wake of COVID-19, the growth rate rebounded to 0.2% in 2023 and 0.1% in 2024, but slowed to a mere 0.02% increase last year.

Domestic citizens accounted for 95.9% of the total at 49.71 million, a decrease of 50,000 from the previous year.

The domestic population has been on a downward trend for five consecutive years starting from 2021, driven by low birth rates and other factors.

In contrast, foreign nationals accounted for 4.1% at 2.11 million, increasing by 70,000 from the previous year.

This growth appears to have been influenced by an increase in international students, trainees, and seasonal workers.

The foreign population has shown a continuous upward trend, except for a slight decline from 2020 to 2021 due to the COVID-19 pandemic.

By age group, foreign nationals in their 30s were the most numerous at 573,000 (27.2%), followed by those in their 20s at 538,000 (25.5%), and those in their 40s at 349,000 (16.6%).

The proportion of the working-age population among foreign nationals was 89.3%, which is 20.9 percentage points higher than the 68.4% recorded for domestic citizens.

(Photo: Provided by Yonhap News TV, Yonhap News)