Drivers of the growth of marginal part-time work and policy recommendations

Since the 2010s, marginal part-time work has grown steadily in South Korea. Marginal part-time workers are generally defined as those whose contractual working hours average fewer than 15 hours per week over a four-week period. Because this study relies on monthly working-hour data, the analysis defines marginal part-time workers as those with fewer than 60 contractual hours per month. Data from the Survey on Labor Conditions by Employment Type show that the share of marginal part-time workers among wage workers rose from 3.7% (487,000 workers) in 2012 to 8.5% (1.538 million workers) in 2024- more than doubling over 12 years (Figure 1, left). The increase is particularly pronounced among newly hired workers with less than one year of tenure, for whom the share of marginal part-time workers has exceeded 20% since the early 2020s. Once regarded as an atypical employment arrangement (Hwang, 2004), marginal part-time work now constitutes a substantial segment of the labor market. Despite their growing prevalence, marginal part-time workers have low participation rates under the basic worker protection system, including social insurance, and there is little evidence of improvement over time. Examining the share of part-time workers covered by all three social insurance schemes-employment insurance, health insurance, and national pension-by working-hour range reveals a clear contrast: enrollment rates have increased markedly over the past 15 years for general part-time workers but have remained low for marginal parttime workers (Figure 1, right). In other words, marginal part-time work is a form of employment that falls within a blind spot in South Korea's worker protection framework.