One-person families numbered 6.64 million last year, up 27.5 per cent from five years earlier and accounting for 31.7 per cent of the total 20.93 million, according to the data by Statistics Korea.
By age, men took up 49.7 per cent of single-person households, with their number soaring 42.7 per cent over the cited period, reports Yonhap News Agency.
The number of one-person households composed of women rose 15.3 per cent.
One-person households have been on a steady rise since 2015, when the percentage of people living alone hit 27.2 per cent.
The data came as many young people are delaying marriage because they cannot find decent jobs amid a prolonged economic slowdown and skyrocketing housing prices, according to Statistics Korea.
Of the total one-member households, 50.3 per cent were not married, up from 43.8 per cent five years earlier.
People aged 29 and younger accounted for the largest slice of 20.2 per cent last year, followed by those aged 70 and older with 18.1 per cent.
The number of households having a working single member came to 4.11 million last year, accounting for 61.9 per cent of all one-person families.
The data also showed 41.2 per cent of single-member households lived in homes while paying monthly rent last year, trailed by those with their own homes with 34.3 per cent and people living in homes on lease called "jeonse", with 17.5 per,cent.
Under South Korea's decades-old jeonse system, tenants pay a large lump-sum deposit, known as key money, to the landlord, which is then returned at the end of the rental agreement, which usually lasts two years.
During the lease period, the tenants do not pay monthly rent.
(IANS)
