The number of South Koreans working multiple jobs surpassed 500,000 in the first quarter of this year, with older people taking up a large proportion of such workers.

A total of 552,000 people here had at least one additional job while working full time in the first quarter, according to Statistics Korea data. This marked a 22.4 percent increase compared to the 451,000 tallied in the same period in 2023.

While the overwhelming majority of the working population still only has one job, the percentage of multiple jobholders has increased from 1.34 percent in the first quarter of 2019 to 1.97 percent last year.

Multiple jobholders were most common in the 60-and-above age group, with 194,000 people working side jobs. Among workers in their 50s, 118,000 worked more than one job, while there were 115,000 multiple jobholders in their 40s, 71,000 in their 30s, and 53,000 aged between 15 and 29.

While the younger population was still least likely to work side jobs, data showed a steep increase in multiple jobholders in that demographic. The number of multiple jobholders in the 15-29 age group marked a steeper increase rate than any other age group with 30.9 percent, followed by a 27.7 percent increase among workers in their 40s.

The biggest increase occurred in the 60-and-above age group, where an additional 39,000 people worked side jobs in the first quarter of this year, a 25.1 percent jump on-year.

In comparison, the number of multiple jobholders increased by 25,000 among the 40-somethings, by 15,000 among those in their 50s, by 12,400 among those in the 15-29 age group, and by 9,300 among those in their 30s.

The official retirement age in South Korea is 60, but an increasing number of older people were found to still be working. According to Statistics Korea, 6.22 million people aged 60 and above were in employment in 2023, a figure that has been increasing every year from 4.32 million in 2018.

The number of workers aged 60 and above hit the highest level in the country's history, accounting for 21.8 percent of all employees in the country.

While a growing number of people are working more than one job, studies have shown that the rise in income has not been proportionate to the increased working hours.

In a December report by the state-run Korea Labor Institute, multiple jobholders made an average 2.94 million won ($2,127) a month in 2022. This was 210,000 won more than those with a single job, but their hourly wage of 13,000 won was lower than the 16,000 won made on an hourly basis by those working one job.

Researchers noted that multiple jobholders generally work in poorer conditions.

The most significant increase in multiple jobholders occurred among women and people aged over 60.

The research showed that 49.6 percent of multiple jobholders in 2022 were aged at least 60, up by 7.7 percent compared to 2017, while 46.1 percent of them were women, up by 5.4 percent in the same period.

Older people in South Korea generally have a lower income due to them being past retirement age, and the country has the largest wage gap between the genders out of all the members of the Organization for Economic Cooperation and Development, with the gap being 31.2 percent as of 2022.

Researchers noted that such an increase in the number of multiple jobholders may be due to a lack of jobs with good wages and benefits, forcing people to find additional income despite the poorer conditions.