South Korea: tax, residence and foreign companies

Residence and the limited foreign-income rule

Korean residence depends on domicile or the applicable 183-day residence test. For a qualifying foreign national whose Korean domicile or residence totals no more than five years in the preceding ten, foreign-source income is generally within the charge when paid in or remitted to Korea. Establish the residence history and source of each category before applying that limitation.

Work performed in Korea does not become foreign-source merely because a foreign company pays it to an overseas account. Keep contracts, work-location records and payroll evidence. Separate earned income, dividends and return of previously accumulated capital in transfer records. The 2026 NTS individual guide covers the 2025 return year; the current statute and the relevant year must be checked when preparing a future return.

Compare the foreign-worker election with normal taxation

Article 18-2 provides the 19% national employment-income election for eligible foreign workers within the statutory commencement window, currently ending 31 December 2026, and the permitted twenty-year period. It is not a general 19% rate for all of a foreign resident’s income. Local taxes and non-tax employment costs must be considered separately.

The calculation sacrifices the ordinary exemptions, deductions and credits covered by the election. Compare both outcomes using the actual remuneration and benefits. Related-party employer restrictions and exceptions are important for owner-managed businesses. A qualifying engineer incentive is another category and should not be combined with the flat-rate election without confirming the statutory interaction. Preserve the election and employer records for later payroll or tax review.

CFC attribution uses ownership, relationships and a low-tax test

Current article 27 deems distributable retained income of specified foreign corporations to be a dividend attributable to the Korean investor. The low-tax condition compares actual foreign tax with income multiplied by 70% of the highest Korean corporate-tax rate. It is a formula tied to the applicable rate, so an old fixed percentage can become misleading.

The company must also satisfy the related-party condition. The investor scope includes direct or indirect holdings of at least 10%, with specified related-person interests included in that calculation. Foreign trusts similar to the statutory corporate-tax trust categories can be treated separately as foreign corporations. Apply the remaining statutory exclusions and computational rules before quantifying an attribution; retaining profits abroad alone does not prevent a charge.

Effective management and departure are separate exposures

Article 2 treats a company with its head office, principal office or effective place of management in Korea as domestic. A foreign registration therefore does not settle the company’s residence when its founder makes the real decisions from Seoul. Document who controls the company and where that authority is exercised.

Income Tax Act article 118-9 provides a deemed share disposal for specified emigrants with at least five years of Korean domicile or residence in the prior ten years and qualifying major-shareholder status at the preceding year end. It is not a tax on every departing foreign employee. Obtain the decree-level share and value analysis, departure-date valuation and filing advice before the move; an actual sale is not required to trigger the specified rule.

How Offshore Capitalist can help

Share your current residence, nationality, business activities and intended changes through the inquiry form or WhatsApp. We can assess the cross-border issues, explain the work required and coordinate the agreed implementation. For this jurisdiction, local regulated work and government decisions remain with the relevant qualified providers and authorities. We confirm scope and fees before starting.