If a person still can’t/won’t pay via installment plans, the only option is to do manual labor. For how long depends on the amount. See above.
It was recently reported that former President Chun Doo-hwan’s second son Chun Jae-yong went into lockup at a workhouse. Back in August 2015, the Supreme Court of Korea found him guilty of tax evasion and sentenced him to 3 years in prison (4 years probation) + ordered him to pay a criminal fine of 4 bil won. Well, he ultimately paid only 140 mil.
This news created somewhat of an uproar here in Korea. Chun was to be locked up for 965 days in lieu of paying the remaining 3.86 bil won. This meant he’ll be paying off his fine at a pace of roughly 4 mil won a day! Doing relatively light manual labor! (e.g., cleaning, folding envelopes…)
This is because Article 69(2) of the Criminal Act (형법) does not allow for such lockups to last for more than 3 years (regardless of the amount). The idea behind that: if a lockup is too long, it essentially becomes a prison sentence (not a criminal fine). But many see this as a loophole.
Thanks for reading!
FYI: A minor criminal fine is called “과료” for which the max lockup period is 29 days. “과료” and “벌금” are both criminal punishments. In contrast, fines in the form of “범칙금” or “과태료” are not.