Income Tax for Foreign Residents in Korea
Two questions decide a foreign worker's Korean tax position: whether you are a resident, and if so, how long you have been one. Residents are in principle taxed on worldwide income, non-residents only on Korean-source income. But Korea softens the first rule for foreign nationals through a long-standing concession, and offers an alternative flat-rate method that is sometimes — not always — better than the ordinary progressive calculation.
Who this affects
- Foreign nationals employed in Korea, whether locally hired or seconded
- Foreign residents holding income or assets outside Korea
- Teachers, engineers and researchers, some of whom have treaty-based relief
- Anyone approaching five years of residence in Korea
Residency, not visa type, sets the scope
Korea looks at whether you have a domicile here, or a place of residence for 183 days or more. Your visa category matters for immigration, but it is the residency test that determines whether Korea reaches your foreign income.
The five-year concession limits worldwide taxation
A long-standing rule means a foreign national who has been resident for five years or less within a ten-year period is generally taxed on foreign-source income only to the extent it is paid in or remitted to Korea. Crossing that threshold changes your exposure, and it is worth knowing the date in advance.
The flat-rate election is a comparison, not an upgrade
Foreign workers may elect a single flat rate on employment income instead of the progressive scale — but electing it means giving up deductions, credits and exemptions. It tends to favour higher earners with few deductions, and to lose money for those with families and substantial deductible spending. Run both.
Treaties can override the domestic outcome
Where your home country has a treaty with Korea, specific provisions for teaching, research or short assignments may exempt income Korea would otherwise tax. Treaty relief generally has to be claimed with documentation, not applied automatically.
Common questions
Does Korea tax the savings I keep in my home country?
It depends on residency and how long you have been resident. Under the five-year concession, foreign-source income is generally taxed only where paid in or remitted to Korea. Once you pass that point, worldwide taxation applies more fully.
Should I elect the flat rate?
Only after comparing. It removes deductions and credits, so it favours high earners with little to deduct. For someone with dependants, housing and medical spending, the ordinary calculation frequently wins.
I'm leaving Korea mid-year. What do I need to do?
Departure usually triggers an early settlement of employment income through your employer before you go. Getting this done before you leave is much easier than trying to resolve it from abroad.
Official sources
General information, not tax advice. Rules and thresholds change, and how they apply depends on your circumstances — confirm with a licensed professional before acting.